Journal articles on the topic 'Alerting responses'
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Yu, Y. H., and W. W. Blessing. "Cutaneous vasoconstriction in conscious rabbits during alerting responses detected by hippocampal theta-rhythm." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 272, no. 1 (January 1, 1997): R208—R216. http://dx.doi.org/10.1152/ajpregu.1997.272.1.r208.
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We determined whether alerting stimuli cause cutaneous vasoconstriction in conscious rabbits. We compared ear blood flow with renal, mesenteric, and femoral flows at rest and in response to nonnoxious alerting stimuli, which induced theta-rhythm (4-9 Hz) in the simultaneously recorded hippocampal electroencephalogram (EEG). theta-Inducing stimuli (e.g., whistles and fur touches) reduced ear flow by 95 +/- 6%, commencing 1-2 s after the EEG change and lasting 45 s. Renal flow did not significantly change with alerting stimuli, mesenteric and femoral flows slightly decreased, arterial pressure transiently rose (+10 +/- 3 mmHg), and heart rate fell (+43 +/- 9 beats/min). At rest, the coefficient of variation for ear flow (62 +/- 6%) was greater than for other flows (P < 0.01). Phentolamine (1 mg/kg iv) reduced this coefficient to 29 +/- 4% (P < 0.01). Our study demonstrates that alerting responses in conscious rabbits are associated with selective cutaneous vasoconstriction, without increase in flow to skeletal muscle.
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Kadlaskar, Girija, Sophia Bergmann, Rebecca McNally Keehn, Amanda Seidl, and Brandon Keehn. "Equivalent Behavioral Facilitation to Tactile Cues in Children with Autism Spectrum Disorder." Brain Sciences 11, no. 5 (May 13, 2021): 625. http://dx.doi.org/10.3390/brainsci11050625.
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The alerting network, a subcomponent of attention, enables humans to respond to novel information. Children with ASD have shown equivalent alerting in response to visual and/or auditory stimuli compared to typically developing (TD) children. However, it is unclear whether children with ASD and TD show equivalent alerting to tactile stimuli. We examined (1) whether tactile cues affect accuracy and reaction times in children with ASD and TD, (2) whether the duration between touch-cues and auditory targets impacts performance, and (3) whether behavioral responses in the tactile cueing task are associated with ASD symptomatology. Six- to 12-year-olds with ASD and TD participated in a tactile-cueing task and were instructed to respond with a button press to a target sound /a/. Tactile cues were presented at 200, 400, and 800 ms (25% each) prior to the auditory target. The remaining trials (25%) were presented without tactile cues. Findings suggested that both groups showed equivalent alerting responses to tactile cues. Additionally, all children were faster to respond to auditory targets at longer cue–target intervals. Finally, there was an association between rate of facilitation and RRB scores in all children, suggesting that patterns of responding to transient phasic cues may be related to ASD symptomatology.
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Huggins, Thomas Jack, Lili Yang, Jin Zhang, Marion Lara Tan, and Raj Prasanna. "Psychological Effects of Dominant Responses to Early Warning Alerts." International Journal of Ambient Computing and Intelligence 12, no. 3 (July 2021): 1–15. http://dx.doi.org/10.4018/ijaci.2021070101.
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Earthquake-related behaviors in Mexico and Japan have highlighted the need to better understand responses to demanding alerting scenarios. Both countries appear to have benefitted from an established early earthquake warning system for several years. However, recent alert responses documented in these settings have been unlikely to protect residents from death or severe injury. This represents a gap between alerting system investments and effectiveness which, among other implications, could result in very large numbers of avoidable injuries and even deaths. To help better understand and address this gap, the current paper presents a theoretical explanation of why alerted residents have responded in the ways that they did. Behavioral and cognitive theories are discussed towards an integrated but simple model of alert response behavior that can be used to guide further research. Challenges and opportunities for this further research are also outlined.
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King, John E., Jorge E. González, and Michael I. Fuller. "Development of a vibrotactile tasking device for use in vestibular assessment." Journal of Vestibular Research 16, no. 1-2 (May 1, 2006): 57–67. http://dx.doi.org/10.3233/ves-2006-161-206.
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The purpose of this study was to design an automated mental alerting task that could be utilized when performing vestibular testing on a broad range of patient populations, including certain difficult-to-test populations, such as the hard-of-hearing. A device was developed that utilized vibrotactile stimuli output to two vibrators placed on the subject's left leg, and responded to activation of two momentary pushbuttons controlled by the subjects. Fourteen normal-hearing subjects without history or symptoms of vestibular involvement participated. Each participant underwent three mental-alerting conditions, defined as no task, verbal task, or vibrotactile task. Each condition involved four irrigations of the ear canals, two with warm water and two with cool water. The resultant nystagmus was recorded and analyzed using four measures to compare the effect of the mental alerting task condition. No significant difference was found between verbal and vibrotactile alerting both of which provided better responses than the no alerting task (F=8.443; df=2,13; p=0.001). Between-subjects analysis showed that the number of gaps, which are undesirable periods of absent nystagmus during test recordings, was smallest for the verbal and vibrotactile tasks, and largest for the no task condition. Overall, the results showed that the vibrotactile tasking device (VTD) is an effective alternative means of providing mental alerting during vestibular testing, specifically that of caloric examination.
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Monk, Kevin J., Lisa Fern, R. Conrad Rorie, and Zachary Roberts. "Utility of Visual and Auditory Warning Alerting for Traffic Avoidance during UAS Operations." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 62, no. 1 (September 2018): 1515–19. http://dx.doi.org/10.1177/1541931218621343.
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Minimum Operational Performance Standards (MOPS) are being developed to support the integration of Unmanned Aircraft Systems (UAS) in the National Airspace System (NAS). Input from subject matter experts and multiple research studies have informed display requirements for Detect-and-Avoid (DAA) systems aimed at supporting timely and appropriate pilot responses to collision hazards. DAA alerting is designed to inform pilots of potential threats to “DAA well clear”; the two highest alert levels – caution and warning – indicate how soon pilot action is required and whether there is adequate time to coordinate with the air traffic controller (ATC). Additional empirical support is needed to clarify the extent to which warning-level alerting impacts DAA task performance. The present study explores the differential effects of the auditory and visual cues provided by the DAA Warning alert, and performance implications compared to caution-only alerting are discussed.
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Bondarenko, Evgeny, Deborah M. Hodgson, and Eugene Nalivaiko. "Amygdala mediates respiratory responses to sudden arousing stimuli and to restraint stress in rats." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 306, no. 12 (June 15, 2014): R951—R959. http://dx.doi.org/10.1152/ajpregu.00528.2013.
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Both human and animal studies have demonstrated that respiratory parameters change in response to presentation of alerting stimuli, as well as during stress, yet central neuronal pathways that mediate such responses remain unknown. The aim of our study was to investigate the involvement of the amygdala in mediating respiratory responses to stressors of various intensities and duration. Adult male Wistar rats ( n = 8) received microinjections of GABAA agonist muscimol or saline into the amygdala bilaterally and were subjected to a respiratory recording using whole body plethysmography. Presentation of acoustic stimuli (500-ms white noise, 40–90 dB) caused transient responses in respiratory rate that were proportional to the stimulus intensity, ranging from +13 ± 9 cpm to +276 ± 67 cpm for 40- and 90-dB stimuli, respectively. Inhibition of the amygdala significantly suppressed respiratory rate responses to the high-intensity stimuli (70–90 dB). Submitting rats to the restraint stress significantly elevated the mean respiratory rate (+72 ± 8 cpm) and the dominant respiratory rate (+51 ± 12 cpm), as well as the fraction of high-frequency respiratory rate (+10 ± 3%). Inhibition of the amygdala by muscimol significantly suppressed these responses. We conclude that the amygdala is one of the key structures that are essential for expression of respiratory responses to stressful or alerting stimuli in rats.
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Casto, R., T. Nguyen, and M. P. Printz. "Characterization of cardiovascular and behavioral responses to alerting stimuli in rats." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 256, no. 5 (May 1, 1989): R1121—R1126. http://dx.doi.org/10.1152/ajpregu.1989.256.5.r1121.
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Freely moving rats exhibit complex motor and cardiovascular responses to tactile stimulation (12.5 psi air puff, 100-ms duration). In naive Wistar-Kyoto rats, the behavioral response is characterized by a short-latency (25 +/- 1 ms) jumping event, the magnitude of which habituates to repeated stimuli. In a paradigm of consecutive tactile stimuli, each delivered at 30-s intervals, the arterial pressure (AP) response is consistent in profile (36.4 +/- 1.7 mmHg, initial stimulus) and habituates rapidly (15.4 +/- 2.2 mmHg, at 20th stimulus). Rates of habituation of the jumping behavior and AP increase are similar and significantly correlated (P less than 0.01), suggesting partial common mediation. Heart rate changes are bimodal and highly dependent on stimulus number. Initial stimuli elicit bradycardia (-42 +/- 7 beats/min), habituating to extinction by stimulus 10. A temporally delayed tachycardia becomes evident by trial 5 (19 +/- 5 beats/min) and persists unchanged throughout the remainder of the 30-stimulus session. Delayed tachycardia may represent activation of secondary autonomic mechanisms. The nature of cardiovascular responses elicited by the tactile stimulus suggests a somatomotor reflex mediated through the ventrolateral medulla. Adrenal enucleation exaggerated the magnitude of transient bradycardia and abolished extinction of bradycardia with repeated stimuli. Adrenal medullary secretion has only minor importance in direct mediation of the response, but this study suggests that adrenal function plays an important role in tonically setting the level of cardiac responsiveness to parasympathetic vs. sympathetic stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)
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Meyer, Joachim. "Evaluating alerting systems from descriptions." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 61, no. 1 (September 2017): 307. http://dx.doi.org/10.1177/1541931213601557.
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Decisions in almost all domains of life receive support from automation in the form of alerts, binary cues, recommendations, etc. People often use automation or decision aids without having experience with the system, because the system may be new or because they rarely use it. When such experience is unavailable, people will base their use of the system on information they may have received about it and on descriptions, often given as probabilities or proportions. Examples are the sensitivity and specificity of a diagnostic procedure in medicine or the True Positive and False Positive rates of a detector. People use these descriptions to decide to what extent they can rely on the information. So far, it is unclear which aspects of the information about a system determine people’s evaluation of the system from a description. These evaluations will determine the trust they put in the indications from the system and the adjustment of system properties, such as thresholds. To gain some insights into this issue, we conducted an experiment. We developed descriptions of 12 systems in a quality control setting, in which participants had to detect faulty items in a production process. We used Signal Detection Theory (Green & Swets, 1966) to determine the system properties. The systems differed in d’ (1.5 or 2.5), the threshold setting lnβ (-1, 0 or 1) and the prior probability for a signal pS (.05 or .2). Half of the participants saw diagnostic values, receiving descriptions in terms of the probabilities of Hit and False Alarms, while the other half saw descriptions as predictive values, receiving the Positive Predictive Value (PPV) and the Negative Predictive Value (NPV) of each system. In the past, we have shown that people adjust system thresholds better when they see predictive values (Botzer, Meyer, Bak, & Parmet, 2010). Fifty-six students evaluated the systems in a classroom setting on a scale between 0 (completely useless) and 10 (perfect). In addition to the d’ and lnβ, which we specified when we designed the systems, we also computed for each system the Probability of Correct Indication (pCorrect), the Expected Value (given the costs and benefits in the description), and the transmitted information according to Information Theory. We analyzed the results with multivariate analyses of variance and by computing the correlations between the evaluations and system properties. The results showed that participants’ responses were mainly correlated with d’. The effects of the threshold setting lnβ and of pS were small, compared to the effects of d’. The correlations with the Expected Value and the transmitted information were smaller and could be explained through d’. Thus, people evaluated a system in terms of its ability to differentiate between signal and noise. They did not evaluate the system according to the economic value it provided or the transmitted information. In addition, participants evaluated systems with different thresholds (lnβ) similarly. This means that in our experiment participants did not differentiate between more and less appropriate threshold settings. The ability to identify better or worse settings is important, because these settings are often the main system parameter users can adjust. These findings, in addition to the inherent problems that already exist in user adjustments of systems (Meyer & Sheridan, 2017), make it unlikely that people can adjust system settings correctly.
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Yu, Ying-Hui, and W. W. Blessing. "Acute increases in forebrain blood flow during alerting responses in conscious rabbits." Brain Research 767, no. 1 (August 1997): 1–7. http://dx.doi.org/10.1016/s0006-8993(97)00439-3.
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Saunders, Jessie K., Brad T. Aagaard, Annemarie S. Baltay, and Sarah E. Minson. "Optimizing Earthquake Early Warning Alert Distance Strategies Using the July 2019 Mw 6.4 and Mw 7.1 Ridgecrest, California, Earthquakes." Bulletin of the Seismological Society of America 110, no. 4 (June 9, 2020): 1872–86. http://dx.doi.org/10.1785/0120200022.
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ABSTRACT The ShakeAlert earthquake early warning system aims to alert people who experience modified Mercalli intensity (MMI) IV+ shaking during an earthquake using source estimates (magnitude and location) to estimate median-expected peak ground motions with distance, then using these ground motions to determine median-expected MMI and thus the extent of MMI IV shaking. Because median ground motions are used, even if magnitude and location are correct, there will be people outside the alert region who experience MMI IV shaking but do not receive an alert (missed alerts). We use 91,000 “Did You Feel It?” survey responses to the July 2019 Mw 6.4 and Mw 7.1 Ridgecrest, California, earthquakes to determine which ground-motion to intensity conversion equation (GMICE) best fits median MMI with distance. We then explore how incorporating uncertainty from the ground-motion prediction equation and the GMICE in the alert distance calculation can produce more accurate MMI IV alert regions for a desired alerting strategy (e.g., aiming to alert 95% of people who experience MMI IV+ shaking), assuming accurate source characterization. Without incorporating ground-motion uncertainties, we find MMI IV alert regions using median-expected ground motions alert fewer than 20% of the population that experiences MMI IV+ shaking. In contrast, we find >94% of the people who experience MMI IV+ shaking can be included in the MMI IV alert region when two standard deviations of ground-motion uncertainty are included in the alert distance computation. The optimal alerting strategy depends on the false alert tolerance of the community due to the trade-off between minimizing missed and false alerts. This is especially the case for situations like the Mw 6.4 earthquake when alerting 95% of the 5 million people who experience MMI IV+ also results in alerting 14 million people who experience shaking below this level and do not need to take protective action.
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Lok, Renske, Karin C. H. J. Smolders, Domien G. M. Beersma, and Yvonne A. W. de Kort. "Light, Alertness, and Alerting Effects of White Light: A Literature Overview." Journal of Biological Rhythms 33, no. 6 (September 7, 2018): 589–601. http://dx.doi.org/10.1177/0748730418796443.
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Light is known to elicit non–image-forming responses, such as effects on alertness. This has been reported especially during light exposure at night. Nighttime results might not be translatable to the day. This article aims to provide an overview of (1) neural mechanisms regulating alertness, (2) ways of measuring and quantifying alertness, and (3) the current literature specifically regarding effects of different intensities of white light on various measures and correlates of alertness during the daytime. In general, the present literature provides inconclusive results on alerting effects of the intensity of white light during daytime, particularly for objective measures and correlates of alertness. However, the various research paradigms employed in earlier studies differed substantially, and most studies tested only a limited set of lighting conditions. Therefore, the alerting potential of exposure to more intense white light should be investigated in a systematic, dose-dependent manner with multiple correlates of alertness and within one experimental paradigm over the course of day.
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Smith, Jonathan J., Kiseko Shionoya, Regina M. Sullivan, and Donald A. Wilson. "Auditory Stimulation Dishabituates Olfactory Responses via Noradrenergic Cortical Modulation." Neural Plasticity 2009 (2009): 1–6. http://dx.doi.org/10.1155/2009/754014.
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Dishabituation is a return of a habituated response if context or contingency changes. In the mammalian olfactory system, metabotropic glutamate receptor mediated synaptic depression of cortical afferents underlies short-term habituation to odors. It was hypothesized that a known antagonistic interaction between these receptors and norepinephrineß-receptors provides a mechanism for dishabituation. The results demonstrate that a 108 dB siren induces a two-fold increase in norepinephrine content in the piriform cortex. The same auditory stimulus induces dishabituation of odor-evoked heart rate orienting bradycardia responses in awake rats. Finally, blockade of piriform cortical norepinephrineß-receptors with bilateral intracortical infusions of propranolol (100 μM) disrupts auditory-induced dishabituation of odor-evoked bradycardia responses. These results provide a cortical mechanism for a return of habituated sensory responses following a cross-modal alerting stimulus.
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EDWARDS, Clare M., Janice M. MARSHALL, and M. PUGH. "Lack of habituation of the pattern of cardiovascular response evoked by sound in subjects with primary Raynaud's disease." Clinical Science 95, no. 3 (September 1, 1998): 249–60. http://dx.doi.org/10.1042/cs0950249.
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1.The vasospasm of primary Raynaud's disease can be triggered by acute emotional stress. We have studied the pattern of cardiovascular response evoked by acute emotional stress, a sound stimulus of 90 ;dB, 2 ;kHz for 30 ;s, in eight subjects with primary Raynaud's disease and in eight age- and sex-matched controls, the sound being repeated five times on each of days 1, 3 and 5. 2.In controls, the first sound evoked the pattern of the alerting response that is characteristic of acute emotional stress: a rise in arterial pressure and heart rate, a decrease in vascular conductance in the cutaneous circulation of the digit, assessed by laser Doppler recording of erythrocyte (red cell) flux in the digit divided by arterial pressure, and an increase in forearm muscle vascular conductance, assessed from forearm blood flow recorded by venous occlusion plethysmography divided by arterial pressure. 3.In the subjects with primary Raynaud's disease, baselines of arterial pressure, digital cutaneous vascular conductance and forearm vascular conductance were not significantly different from those of the controls and they too showed the alerting response to the first sound, the magnitudes of the changes being comparable to those of the controls. 4.In both the controls and subjects with primary Raynaud's disease, the evoked responses were consistent on repetition of the sound on day 1. In contrast, judging from the means of the changes evoked on each day, the controls showed habituation of the individual components of the alerting response over days 1, 3 and 5, whereas the subjects with primary Raynaud's disease showed no habituation of either the forearm muscle vasodilatation or the digital vasoconstriction. Conversely, the decrease in digital cutaneous vascular conductance evoked by a single deep breath was fully reproducible in both controls and subjects with primary Raynaud's disease when tested at the beginning and end of each experimental day. 5.These results allow the novel conclusion that subjects with primary Raynaud's disease have an abnormality of the central neural modulation of the brain stem areas that integrate the cardiovascular components of the alerting response to acute emotional stress, such that habituation of the vasodilator and vasoconstrictor components of the response on repetition of the stimulus is impaired. We propose that such persistence of vasoconstrictor responses to stressful stimuli predisposes to vasospasm, particularly if neurally mediated vasoconstriction is reinforced by locally released vasoconstrictor factors.
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Müller-Ribeiro, Flávia C. F., Ann K. Goodchild, Simon McMullan, Marco A. P. Fontes, and Roger A. L. Dampney. "Coordinated autonomic and respiratory responses evoked by alerting stimuli: Role of the midbrain colliculi." Respiratory Physiology & Neurobiology 226 (June 2016): 87–93. http://dx.doi.org/10.1016/j.resp.2015.10.012.
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Garralda, M. Elena, John Connell, and David C. Taylor. "Psychophysiological anomalies in children with emotional and conduct disorders." Psychological Medicine 21, no. 4 (November 1991): 947–57. http://dx.doi.org/10.1017/s0033291700029937.
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SYNOPSISWe studied patterns of psychophysiological (skin conductance, heart rate) reactivity to sounds and to situations with varying emotional and alerting connotations in child psychiatric out-patients and in healthy controls. Children with emotional disorders were particularly reactive to situations with aversive components, while conduct disorder subjects showed increased reactivity to pleasant situations and decreased responses to neutral but high-intensity stimulation and to withdrawal of stimulation in silence periods. The results indicate patterns of biological reactivity which may underlie different psychiatric disturbances in children.
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Ben-Asher, Noam, and Joachim Meyer. "The Triad of Risk-Related Behaviors (TriRB): A Three-Dimensional Model of Cyber Risk Taking." Human Factors: The Journal of the Human Factors and Ergonomics Society 60, no. 8 (July 10, 2018): 1163–78. http://dx.doi.org/10.1177/0018720818783953.
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Objective: We identify three risk-related behaviors in coping with cyber threats—the exposure to risk a person chooses, use of security features, and responses to security indications. The combinations of behaviors that users choose determine how well they cope with threats and the severity of adverse events they experience. Background: End users’ coping with risks is a major factor in cybersecurity. This behavior results from a combination of risk-related behaviors rather than from a single risk-taking tendency. Method: In two experiments, participants played a Tetris-like game, attempting to maximize their gains, while exogenous occasional attacks could diminish earnings. An alerting system provided indications about possible attacks, and participants could take protective actions to limit the losses from attacks. Results: Variables such as the costs of protective actions, reliability of the alerting system, and attack severity affected the three behaviors differently. Also, users dynamically adjusted each of the three risk-related behaviors after gaining experience with the system. Conclusion: The results demonstrate that users’ risk taking is the complex combination of three behaviors rather than the expression of a general risk-taking tendency. The use of security features, exposure to risk, and responses to security indications reflect long-term strategy, short-term tactical decisions, and immediate maneuvering in coping with risks in dynamic environments. Application: The results have implications for the analysis of cybersecurity-related decisions and actions as well as for the evaluation and design of systems and targeted interventions in other domains.
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Sanford, Larry D., William A. Ball, Adrian R. Morrison, Richard J. Ross, and Graziella Mann. "Peripheral and central components of alerting: Habituation of acoustic startle, orienting responses, and elicited waveforms." Behavioral Neuroscience 106, no. 1 (1992): 112–20. http://dx.doi.org/10.1037/0735-7044.106.1.112.
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Spitschan, Manuel, Rafael Lazar, Ebru Yetik, and Christian Cajochen. "No evidence for an S cone contribution to acute neuroendocrine and alerting responses to light." Current Biology 29, no. 24 (December 2019): R1297—R1298. http://dx.doi.org/10.1016/j.cub.2019.11.031.
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Orr, R. S., A. S. Jordan, P. Catcheside, N. A. Saunders, and R. D. McEvoy. "Sustained isocapnic hypoxia suppresses the perception of the magnitude of inspiratory resistive loads." Journal of Applied Physiology 89, no. 1 (July 1, 2000): 47–55. http://dx.doi.org/10.1152/jappl.2000.89.1.47.
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The sensation of increased respiratory resistance or effort is likely to be important for the initiation of alerting or arousal responses, particularly in sleep. Hypoxia, through its central nervous system-depressant effects, may decrease the perceived magnitude of respiratory loads. To examine this, we measured the effect of isocapnic hypoxia on the ability of 10 normal, awake males (mean age = 24.0 ± 1.8 yr) to magnitude-scale five externally applied inspiratory resistive loads (mean values from 7.5 to 54.4 cmH2O · l−1 · s). Each subject scaled the loads during 37 min of isocapnic hypoxia (inspired O2 fraction = 0.09, arterial O2 saturation of ∼80%) and during 37 min of normoxia, using the method of open magnitude numerical scaling. Results were normalized by modulus equalization to allow between-subject comparisons. With the use of peak inspiratory pressure (PIP) as the measure of load stimulus magnitude, the perception of load magnitude (Ψ) increased linearly with load and, averaged for all loaded breaths, was significantly lower during hypoxia than during normoxia (20.1 ± 0.9 and 23.9 ± 1.3 arbitrary units, respectively; P = 0.048). Ψ declined with time during hypoxia ( P = 0.007) but not during normoxia ( P= 0.361). Our result is remarkable because PIP was higher at all times during hypoxia than during normoxia, and previous studies have shown that an elevation in PIP results in increased Ψ. We conclude that sustained isocapnic hypoxia causes a progressive suppression of the perception of the magnitude of inspiratory resistive loads in normal subjects and could, therefore, impair alerting or arousal responses to respiratory loading.
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Han, Suk Won, Hana P. Eaton, and René Marois. "Functional Fractionation of the Cingulo-opercular Network: Alerting Insula and Updating Cingulate." Cerebral Cortex 29, no. 6 (May 11, 2018): 2624–38. http://dx.doi.org/10.1093/cercor/bhy130.
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Abstract The anterior insula (AI) and dorsal anterior cingulate cortex (dACC) are engaged in various cognitive and affective processes. An influential account posits that the AI and dACC’s ubiquitous engagements reflect their role in the transient capture of attention by salient stimuli. Using fMRI here we tested this claim and functionally dissociated these regions. In the first experiment, we compared these regions’ responses to emotion-laden and emotion-neutral salient “oddball” movie events. We found that while the AI only responded transiently to the onset and offset of neutral events, its response to affective events was sustained, challenging the transient attention capture account. By contrast, dACC remained transient regardless of event type. A second experiment distinguished the information encoded by these brain regions with the presentation of behaviorally salient events that require either maintaining the current task set or updating to a different one; the AI was found to signal the presence of the behaviorally relevant events, while the dACC was associated with switching of attention settings in response to the events. We conclude that AI and dACC are involved in signaling the presence of potentially or de facto behaviorally significant events and updating internal attention settings in response to these events, respectively.
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Hanifin, J. P., S. W. Lockley, K. Cecil, K. West, M. Jablonski, B. Warfield, M. James, et al. "Randomized trial of polychromatic blue-enriched light for circadian phase shifting, melatonin suppression, and alerting responses." Physiology & Behavior 198 (January 2019): 57–66. http://dx.doi.org/10.1016/j.physbeh.2018.10.004.
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Sheu, Katherine M., and Alexander Hoffmann. "Functional Hallmarks of Healthy Macrophage Responses: Their Regulatory Basis and Disease Relevance." Annual Review of Immunology 40, no. 1 (April 26, 2022): 295–321. http://dx.doi.org/10.1146/annurev-immunol-101320-031555.
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Macrophages are first responders for the immune system. In this role, they have both effector functions for neutralizing pathogens and sentinel functions for alerting other immune cells of diverse pathologic threats, thereby initiating and coordinating a multipronged immune response. Macrophages are distributed throughout the body—they circulate in the blood, line the mucosal membranes, reside within organs, and survey the connective tissue. Several reviews have summarized their diverse roles in different physiological scenarios and in the initiation or amplification of different pathologies. In this review, we propose that both the effector and the sentinel functions of healthy macrophages rely on three hallmark properties: response specificity, context dependence, and stimulus memory. When these hallmark properties are diminished, the macrophage's biological functions are impaired, which in turn results in increased risk for immune dysregulation, manifested by immune deficiency or autoimmunity. We review the evidence and the molecular mechanisms supporting these functional hallmarks.
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Sheu, Katherine M., and Alexander Hoffmann. "Functional Hallmarks of Healthy Macrophage Responses: Their Regulatory Basis and Disease Relevance." Annual Review of Immunology 40, no. 1 (April 26, 2022): 295–321. http://dx.doi.org/10.1146/annurev-immunol-101320-031555.
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Macrophages are first responders for the immune system. In this role, they have both effector functions for neutralizing pathogens and sentinel functions for alerting other immune cells of diverse pathologic threats, thereby initiating and coordinating a multipronged immune response. Macrophages are distributed throughout the body—they circulate in the blood, line the mucosal membranes, reside within organs, and survey the connective tissue. Several reviews have summarized their diverse roles in different physiological scenarios and in the initiation or amplification of different pathologies. In this review, we propose that both the effector and the sentinel functions of healthy macrophages rely on three hallmark properties: response specificity, context dependence, and stimulus memory. When these hallmark properties are diminished, the macrophage's biological functions are impaired, which in turn results in increased risk for immune dysregulation, manifested by immune deficiency or autoimmunity. We review the evidence and the molecular mechanisms supporting these functional hallmarks.
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Kohlmeier, Kristi A., Faustino López-Rodríguez, Francisco R. Morales, and Michael H. Chase. "Relationship Between Sensory Stimuli–Elicited IPSPs in Motoneurons and PGO Waves During Cholinergically Induced Muscle Atonia." Journal of Neurophysiology 78, no. 4 (October 1, 1997): 2145–55. http://dx.doi.org/10.1152/jn.1997.78.4.2145.
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Kohlmeier, Kristi A., Faustino López-Rodrı́guez, Francisco R. Morales, and Michael H. Chase. Relationship between sensory stimuli–elicited IPSPs in motoneurons and PGO waves during cholinergically induced muscle atonia. J. Neurophysiol. 78: 2145–2155, 1997. Inhibitory postsynaptic potentials (IPSPs) can be produced in masseter motoneurons by sensory stimuli after the injection of carbachol into the nucleus pontis oralis (NPO) of α-chloralose–anesthetized cats. We have postulated previously that these IPSPs, which are induced in masseter motoneurons by sensory stimuli, arise as the result of phasic activation of the motor inhibitory system that mediates atonia occurring spontaneously during active sleep. In the present study, we determined that sensory stimuli, which excite different sensory pathways, somatosensory and auditory, also elicit ponto-geniculo–occipital (PGO) waves during the carbachol-induced state. Because the elicitation of PGO waves has been hypothesized to be a central sign of activation of alerting mechanisms, we suggest that these stimuli also excite those CNS structures that are involved in the alerting network. The temporal association of the sensory stimuli-elicited IPSPs and PGO waves also was examined by correlating the intracellular response of masseter motoneurons and the extracellular response of lateral geniculate nuclei neurons to somatosensory and auditory stimuli. Sensory stimuli produced an IPSP that had a similar latency from the foot of the elicited PGO wave as that of spontaneously occurring motoneuron IPSPs and PGO waves that occur during both carbachol-induced muscle atonia and naturally occurring active sleep. In addition, the intensity of the stimulus necessary for elicitation of PGO waves was found to be lower than that required for the elicitation of IPSPs in motoneurons. Additionally, evoked responses in masseter motoneurons during the carbachol-induced state were graded in response to increases in stimulus intensity. The preceding data suggest that some type of processing of sensory input occurs such that only those stimuli that are capable of activating alerting mechanisms involved in the generation of PGO waves result in an increase in activity in the motor inhibitory system. We conclude that there may be a functional link between alerting mechanisms involved in the generation of PGO waves and the motor inhibitory system that generates IPSPs in motoneurons. This functional link may serve to preserve atonia, and thus the state of active sleep, from potentially disruptive PGO-related influences that, during other behavioral states, result in motor activation.
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EDWARDS, Clare M., Janice M. MARSHALL, and M. PUGH. "Cardiovascular responses evoked by mild cool stimuli in primary Raynaud's disease: the role of endothelin." Clinical Science 96, no. 6 (May 4, 1999): 577–88. http://dx.doi.org/10.1042/cs0960577.
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In control subjects and in subjects with primary Raynaud's disease, sudden sound evokes the pattern of the alerting response, which includes cutaneous vasoconstriction and vasodilatation in forearm muscle. However, whereas this pattern of response habituates on repetition of the sound stimulus in control subjects, both cutaneous vasoconstriction and muscle dilatation persist in subjects with primary Raynaud's disease. The aim of the present study was to test whether a similar disparity exists between control subjects and those with primary Raynaud's disease for the response to mild cool stimuli, and whether the cutaneous response is accompanied by the release of endothelin-1 (ET-1). In nine subjects with primary Raynaud's disease and in nine matched controls, the left hand was placed in cool water at 16 °C for 2 min five times on each of three experimental sessions on days 1, 3 and 5, with blood being taken from the venous drainage of the cooled hand before and at the end of the second session. In response to the first cool stimulus in Session 1, the subjects with primary Raynaud's disease showed a decrease in digital cutaneous vascular conductance (DCVC) in both the right and left hands, as indicated by a laser Doppler recording of erythrocyte (red cell) flux divided by arterial pressure, and six of the nine subjects showed an increase in forearm vascular conductance (FVC), as indicated by forearm blood flow measured by plethysmography divided by arterial pressure. On repetition of the stimulus in Session 1, there was no change in the magnitude of the increase in FVC, but the evoked decreases in DCVC became more prolonged in both the right and the left hand. Similar responses occurred in Sessions 2 and 3; in Session 2, the ET-1 concentration increased from a baseline value of 2.15±0.26 fM to 2.72±0.37 fM after five stimuli. There was no habituation of the increase in FVC over Sessions 1, 2 and 3, judging from the mean changes in each session. Control subjects also showed a decrease in DCVC in both hands, and in eight out of nine subjects there was an increase in FVC in response to the first cool stimulus in Session 1. However, on repetition of the stimulus in Session 1, the increase in FVC habituated, while there was no prolongation of the decrease in DCVC; in addition, the ET-1 concentration did not change in Session 2 in response to the stimulus (2.07±0.28 compared with 2.29±0.30 fM). Further, the increase in FVC habituated over the three sessions, such that there was a mean decrease in FVC in Session 3. These results indicate that, in subjects with primary Raynaud's disease, there is impairment of the ability of the central nervous system to allow habituation of the cardiovascular components of the alerting response evoked by mild cooling, as with the response to sound. We propose that persistence of the cutaneous vasoconstriction of the alerting response, coupled with increased release of ET-1 secondary to vasoconstriction, prolongs such vasoconstriction and eventually leads to vasospasm.
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Juan, Elsa, Nathalie Ata Nguepnjo Nguissi, Athina Tzovara, Dragana Viceic, Marco Rusca, Mauro Oddo, Andrea O. Rossetti, and Marzia De Lucia. "Evidence of trace conditioning in comatose patients revealed by the reactivation of EEG responses to alerting sounds." NeuroImage 141 (November 2016): 530–41. http://dx.doi.org/10.1016/j.neuroimage.2016.07.039.
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Heinrich, Hartmut, Katrin Busch, Petra Studer, Karlheinz Erbe, Gunther H. Moll, and Oliver Kratz. "Refining the picture of reduced alerting responses in ADHD – A single-trial analysis of event-related potentials." Neuroscience Letters 582 (October 2014): 49–53. http://dx.doi.org/10.1016/j.neulet.2014.08.050.
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Scheepers-Hoeks, Anne-Marie J., Rene J. Grouls, Cees Neef, Eric W. Ackerman, and Erik H. Korsten. "Physicians’ responses to clinical decision support on an intensive care unit—Comparison of four different alerting methods." Artificial Intelligence in Medicine 59, no. 1 (September 2013): 33–38. http://dx.doi.org/10.1016/j.artmed.2013.05.002.
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de Menezes, Rodrigo Cunha Alvim, Youichirou Ootsuka, and William W. Blessing. "Sympathetic cutaneous vasomotor alerting responses (SCVARs) are associated with hippocampal theta rhythm in non-moving conscious rats." Brain Research 1298 (October 2009): 123–30. http://dx.doi.org/10.1016/j.brainres.2009.08.042.
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Alavi, Arash, Gireesh K. Bogu, Meng Wang, Ekanath Srihari Rangan, Andrew W. Brooks, Qiwen Wang, Emily Higgs, et al. "Real-time alerting system for COVID-19 and other stress events using wearable data." Nature Medicine 28, no. 1 (November 29, 2021): 175–84. http://dx.doi.org/10.1038/s41591-021-01593-2.
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AbstractEarly detection of infectious diseases is crucial for reducing transmission and facilitating early intervention. In this study, we built a real-time smartwatch-based alerting system that detects aberrant physiological and activity signals (heart rates and steps) associated with the onset of early infection and implemented this system in a prospective study. In a cohort of 3,318 participants, of whom 84 were infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), this system generated alerts for pre-symptomatic and asymptomatic SARS-CoV-2 infection in 67 (80%) of the infected individuals. Pre-symptomatic signals were observed at a median of 3 days before symptom onset. Examination of detailed survey responses provided by the participants revealed that other respiratory infections as well as events not associated with infection, such as stress, alcohol consumption and travel, could also trigger alerts, albeit at a much lower mean frequency (1.15 alert days per person compared to 3.42 alert days per person for coronavirus disease 2019 cases). Thus, analysis of smartwatch signals by an online detection algorithm provides advance warning of SARS-CoV-2 infection in a high percentage of cases. This study shows that a real-time alerting system can be used for early detection of infection and other stressors and employed on an open-source platform that is scalable to millions of users.
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Vargas Martínez, Cyntia, and Birgit Vogel-Heuser. "Towards Industrial Intrusion Prevention Systems: A Concept and Implementation for Reactive Protection." Applied Sciences 8, no. 12 (December 2, 2018): 2460. http://dx.doi.org/10.3390/app8122460.
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System intrusions violate the security of a system. In order to maintain it, it is necessary to decrease the chances of intrusions occurring or by detecting them as soon as they ensue in order to respond to them in a timely manner. These responses are divided in two types: passive or reactive responses. Passive responses are limited to only notification and alerting; whereas, reactive responses influence the intrusion by undoing or diminishing its consequences. Unfortunately, some reactive responses may influence the underlying system where the intrusion has occurred. This is especially a concern in the field of Industrial Automation Systems, as these systems are critical and have a well-defined set of operational requirements that must be maintained. Hence, automatic reactive responses are often not considered or are limited to human intervention. This paper addresses this issue by introducing a concept for reactive protection that integrates the automatic execution of active responses that do not influence the operation of the underlying Industrial Automation System. This concept takes into consideration architectural and security trends, as well as security and operational policies of Industrial Automation Systems. It also proposes a set of reactive actions that can be taken in the presence of intrusions in order to counteract them or diminish their effects. The feasibility and applicability of the presented concept for Industrial Automation Systems is supported by the implementation and evaluation of a prototypical Reactive Protection System.
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Mohammed, M., K. Kulasekara, R. C. De Menezes, Y. Ootsuka, and W. W. Blessing. "Inactivation of neuronal function in the amygdaloid region reduces tail artery blood flow alerting responses in conscious rats." Neuroscience 228 (January 2013): 13–22. http://dx.doi.org/10.1016/j.neuroscience.2012.10.008.
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Ploner, Markus, Bettina Pollok, and Alfons Schnitzler. "Pain Facilitates Tactile Processing in Human Somatosensory Cortices." Journal of Neurophysiology 92, no. 3 (September 2004): 1825–29. http://dx.doi.org/10.1152/jn.00260.2004.
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Touch and pain are intimately related modalities. Despite a substantial overlap in their cortical representations interactions between both modalities are largely unknown at the cortical level. We therefore used magnetoencephalography and selective nociceptive cutaneous laser stimulation to investigate the effects of brief painful stimuli on cortical processing of touch. Using a conditioning test stimulus paradigm, our results show that painful conditioning stimuli facilitate processing of tactile test stimuli applied 500 ms later. This facilitation applies to cortical responses later than 40 ms originating from primary (S1) and secondary (S2) somatosensory cortices but not to earlier S1 responses. By contrast, tactile conditioning stimuli yield a decrease of early as well as late responses to tactile test stimuli. Control experiments show that pain-induced facilitation of tactile processing is not restricted to the site of the painful conditioning stimulus, whereas auditory conditioning does not yield a comparable facilitation. Apart from a lack of spatial specificity, the facilitating effect of pain closely resembles attentional effects on cortical processing of tactile stimuli. Thus these findings may represent a physiological correlate of an alerting function of pain as a change in the internal state to prepare for processing signals of particular relevance.
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Bulmer, Mark S., Bruno A. Franco, and Edith G. Fields. "Subterranean Termite Social Alarm and Hygienic Responses to Fungal Pathogens." Insects 10, no. 8 (August 5, 2019): 240. http://dx.doi.org/10.3390/insects10080240.
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In social insects, alerting nestmates to the presence of a pathogen should be critical for limiting its spread and initiating social mechanisms of defense. Here we show that subterranean termites use elevated vibratory alarm behavior to help prevent fatal fungal infections. The elevated alarm leads to elevated social hygiene. This requires that termites coalesce so that they can groom each other’s cuticular surfaces of contaminating conidial spores. Groups of 12 Reticulitermes flavipes workers varied in their response when immersed in conidia solutions of nine different strains of Metarhizium. Pathogen alarm displays of short 2–7-second bursts of rapid longitudinal oscillatory movement (LOM), observed over 12 min following a fungal challenge, were positively correlated with the time that workers spent aggregated together grooming each other. The frequency of these LOMs was inversely correlated with fatal fungal infections. The variation in fatalities appeared to be largely attributable to a differential response to Metarhizium brunneum and Metarhizium robertsii in the time spent in aggregations and the frequency of allogrooming. Isolated workers challenged with conidia did not display LOMs, which suggests that the alarm is a conditional social response. LOMs appear to help signal the presence of fungal pathogens whose virulence depends on the level of this emergency alert.
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Chellappa, Sarah L., Antoine U. Viola, Christina Schmidt, Valérie Bachmann, Virginie Gabel, Micheline Maire, Carolin F. Reichert, et al. "Human Melatonin and Alerting Response to Blue-Enriched Light Depend on a Polymorphism in the Clock Gene PER3." Journal of Clinical Endocrinology & Metabolism 97, no. 3 (March 1, 2012): E433—E437. http://dx.doi.org/10.1210/jc.2011-2391.
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Context: Light exposure, particularly at the short-wavelength range, triggers several nonvisual responses in humans. However, the extent to which the melatonin-suppressing and alerting effect of light differs among individuals remains unknown. Objective: Here we investigated whether blue-enriched polychromatic light impacts differentially on melatonin and subjective and objective alertness in healthy participants genotyped for the PERIOD3 (PER3) variable-number, tandem-repeat polymorphism. Design, Setting, and Participants: Eighteen healthy young men homozygous for the PER3 polymorphism (PER35/5and PER34/4) underwent a balanced crossover design during the winter season, with light exposure to compact fluorescent lamps of 40 lux at 6500 K and at 2500 K during 2 h in the evening. Results: In comparison to light at 2500 K, blue-enriched light at 6500 K induced a significant suppression of the evening rise in endogenous melatonin levels in PER35/5 individuals but not in PER34/4. Likewise, PER35/5 individuals exhibited a more pronounced alerting response to light at 6500 K than PER34/4 volunteers. Waking electroencephalographic activity in the theta range (5–7 Hz), a putative correlate of sleepiness, was drastically attenuated during light exposure at 6500 K in PER35/5 individuals as compared with PER34/4. Conclusions: We provide first evidence that humans homozygous for the PER3 5/5 allele are particularly sensitive to blue-enriched light, as indexed by the suppression of endogenous melatonin and waking theta activity. Light sensitivity in humans may be modulated by a clock gene polymorphism implicated in the sleep-wake regulation.
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Kakderi, Christina, Eleni Oikonomaki, and Ilektra Papadaki. "Smart and Resilient Urban Futures for Sustainability in the Post COVID-19 Era: A Review of Policy Responses on Urban Mobility." Sustainability 13, no. 11 (June 7, 2021): 6486. http://dx.doi.org/10.3390/su13116486.
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The COVID-19 pandemic has put lifestyles in question, changed daily routines, and limited citizen freedoms that seemed inalienable before. A human activity that has been greatly affected since the beginning of the health crisis is mobility. Focusing on mobility, we aim to discuss the transformational impact that the pandemic brought to this specific urban domain, especially with regards to the promotion of sustainability, the smart growth agenda, and the acceleration towards the smart city paradigm. We collect 60 initial policy responses related to urban mobility from cities around the world and analyze them based on the challenge they aim to address, the exact principles of smart growth and sustainable mobility that they encapsulate, as well as the level of ICT penetration. Our findings suggest that emerging strategies, although mainly temporary, are transformational, in line with the principles of smart growth and sustainable development. Most policy responses adopted during the first months of the pandemic, however, fail to leverage advancements made in the field of smart cities, and to adopt off-the-shelf solutions such as monitoring, alerting, and operations management.
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Ishizaki, Hisayoshi, Heikki Aalto, Ilmari Pyykkö, and Jukka Starck. "Tullio Phenomenon and Postural Stability: Experimental Study in Normal Subjects and Patients with Vertigo." Annals of Otology, Rhinology & Laryngology 100, no. 12 (December 1991): 976–83. http://dx.doi.org/10.1177/000348949110001205.
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The effect of low-frequency sound (LFS) on postural stability was studied in 55 healthy volunteers and in 152 patients with vertigo due to different types of inner ear disease. The sound pressure levels ranged from 130 to 132 dB and were given at frequencies of 25, 50, and 63 Hz. The duration of each stimulation lasted 30 seconds. The postural responses were measured with a force platform. The LFS stimulation improved the postural stability of the healthy subjects through the alerting response. We did not observe any difference in the body sway according to whether the LFS was delivered with monaural or binaural stimulation. Twenty-six percent of the patients with Meniere's disease, 40% with chronic otitis media with vertigo, and 26% with vertigo of peripheral origin experienced significant postural instability at least at two of the three test frequencies during stimulation with LFS. The results demonstrate that in subjects with different types of inner ear disease the vestibular system starts to respond to LFS. The activation of vestibulospinal responses by LFS seems to be an expression of the Tullio phenomenon.
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Mogg, K., G. A. Salum, B. P. Bradley, A. Gadelha, P. Pan, P. Alvarenga, L. A. Rohde, D. S. Pine, and G. G. Manfro. "Attention network functioning in children with anxiety disorders, attention-deficit/hyperactivity disorder and non-clinical anxiety." Psychological Medicine 45, no. 12 (April 24, 2015): 2633–46. http://dx.doi.org/10.1017/s0033291715000586.
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BackgroundResearch with adults suggests that anxiety is associated with poor control of executive attention. However, in children, it is unclear (a) whether anxiety disorders and non-clinical anxiety are associated with deficits in executive attention, (b) whether such deficits are specific to anxiety versus other psychiatric disorders, and (c) whether there is heterogeneity among anxiety disorders (in particular, specific phobia versus other anxiety disorders).MethodWe examined executive attention in 860 children classified into three groups: anxiety disorders (n = 67), attention-deficit/hyperactivity disorder (ADHD; n = 67) and no psychiatric disorder (n = 726). Anxiety disorders were subdivided into: anxiety disorders excluding specific phobia (n = 43) and specific phobia (n = 21). The Attention Network Task was used to assess executive attention, alerting and orienting.ResultsFindings indicated heterogeneity among anxiety disorders, as children with anxiety disorders (excluding specific phobia) showed impaired executive attention, compared with disorder-free children, whereas children with specific phobia showed no executive attention deficit. Among disorder-free children, executive attention was less efficient in those with high, relative to low, levels of anxiety. There were no anxiety-related deficits in orienting or alerting. Children with ADHD not only had poorer executive attention than disorder-free children, but also higher orienting scores, less accurate responses and more variable response times.ConclusionsImpaired executive attention in children (reflected by difficulty inhibiting processing of task-irrelevant information) was not fully explained by general psychopathology, but instead showed specific associations with anxiety disorders (other than specific phobia) and ADHD, as well as with high levels of anxiety symptoms in disorder-free children.
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Bernardi, Luciano, Stefano Leuzzi, Alberto Radaelli, Claudio Passino, James A. Johnston, and Peter Sleight. "Low-Frequency Spontaneous Fluctuations of R-R Interval and Blood Pressure in Conscious Humans: A Baroreceptor or Central Phenomenon?" Clinical Science 87, no. 6 (December 1, 1994): 649–54. http://dx.doi.org/10.1042/cs0870649.
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1. We have tested the hypothesis that the non-respiratory, low-frequency (around 0.1 Hz) fluctuations of heart rate variability are generated by the baroreflexes, but with a delay caused by the slower response of the efferent sympathetic arm, (compared with the vagus), in 11 healthy subjects (mean age ± SD 27 ± 5 years). 2. In random order, at the onset of 20 s of apnoea starting at end expiration, we applied either 600 ms neck suction (−40 mmHg) to the carotid sinus region, or no stimulus (anticipation control), or a loud whistle (alerting control), every 60s, for 30 min. (i.e. 10 of each ‘stimulus’). We recorded neck pressure, blood pressure (Finapres), R-R interval (ECG), infra-red plethysmographic skin blood flow and respiration (impedance). By subtracting the alerting response from the neck suction response we obtained the responses caused purely by baroreceptor stimulation. 3. The initial reflex bradycardia and hypotension was followed by arteriolar vasoconstriction, presumably due to recompensation by the baroreflex, and then by a further reflex bradycardia—producing a decaying oscillation of the R-R interval about the control R-R. The period of this damped oscillation was 0.103 ± 0.024 Hz, similar to the frequency of the low-frequency peak obtained by power spectral analysis of heart rate variability (0.093 ± 0.016 Hz, not significant) at rest. These two values were significantly correlated in individual subjects (r = 0.715, P < 0.025). 4. These findings support the hypothesis that the low-frequency waves of heart rate variability can be generated from baroreceptor sensed blood pressure fluctuations.
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Princeton, Joy. "When Anthropologists Wear Two Hats: Ethnographer and Health Professional." Practicing Anthropology 15, no. 3 (June 1, 1993): 14–16. http://dx.doi.org/10.17730/praa.15.3.tu025417413p28hv.
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Years after he conducted field work in the Trobriand Islands, Malinowski's revealing description of his inner-most thoughts, feelings, and attitudes about the research site and informants was published posthumously (Diary in the Strict Sense of the Term. New York: Harcourt, Brace and World, 1967). Since that time, personal accounts have appeared more frequently in the anthropological literature, although most are not as poignant and certainly not as pejorative as Malinowski's. These backstage descriptions and confessional tales provide anthropologists with opportunities to examine the ways in which their feelings and attitudes have impacted upon their research. They are especially important to the discipline as teaching tools, as means of alerting others to dilemmas they could face in ethnographic research and of stimulating consideration of alternative responses to such dilemmas.
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Bondarenko, Evgeny, Mirza I. Beig, Deborah M. Hodgson, Valdir A. Braga, and Eugene Nalivaiko. "Blockade of the dorsomedial hypothalamus and the perifornical area inhibits respiratory responses to arousing and stressful stimuli." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 308, no. 10 (May 15, 2015): R816—R822. http://dx.doi.org/10.1152/ajpregu.00415.2014.
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The dorsomedial hypothalamus (DMH) and the perifornical area (DMH/PeF) is one of the key regions of central autonomic processing. Previous studies have established that this region contains neurons that may be involved in respiratory processing; however, this has never been tested in conscious animals. The aim of our study was to investigate the involvement of the DMH/PeF area in mediating respiratory responses to stressors of various intensities and duration. Adult male Wistar rats ( n = 8) received microinjections of GABAA agonist muscimol or saline into the DMH/PeF bilaterally and were subjected to a respiratory recording using whole body plethysmography. Presentation of acoustic stimuli (500-ms white noise) evoked transient responses in respiratory rate, proportional to the stimulus intensity, ranging from +44 ± 27 to +329 ± 31 cycles/min (cpm). Blockade of the DMH/PeF almost completely abolished respiratory rate and tidal volume responses to the 40- to 70-dB stimuli and also significantly attenuated responses to the 80- to 90-dB stimuli. Also, it significantly attenuated respiratory rate during the acclimatization period (novel environment stress). The light stimulus (30-s 2,000 lux) as well as 15-min restraint stress significantly elevated respiratory rate from 95 ± 4.0 to 236 ± 29 cpm and from 117 ± 5.2 to 189 ± 13 cpm, respectively; this response was abolished after the DMH/PeF blockade. We conclude that integrity of the DMH/PeF area is essential for generation of respiratory responses to both stressful and alerting stimuli.
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Schultz, Wolfram. "Predictive Reward Signal of Dopamine Neurons." Journal of Neurophysiology 80, no. 1 (July 1, 1998): 1–27. http://dx.doi.org/10.1152/jn.1998.80.1.1.
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Schultz, Wolfram. Predictive reward signal of dopamine neurons. J. Neurophysiol. 80: 1–27, 1998. The effects of lesions, receptor blocking, electrical self-stimulation, and drugs of abuse suggest that midbrain dopamine systems are involved in processing reward information and learning approach behavior. Most dopamine neurons show phasic activations after primary liquid and food rewards and conditioned, reward-predicting visual and auditory stimuli. They show biphasic, activation-depression responses after stimuli that resemble reward-predicting stimuli or are novel or particularly salient. However, only few phasic activations follow aversive stimuli. Thus dopamine neurons label environmental stimuli with appetitive value, predict and detect rewards and signal alerting and motivating events. By failing to discriminate between different rewards, dopamine neurons appear to emit an alerting message about the surprising presence or absence of rewards. All responses to rewards and reward-predicting stimuli depend on event predictability. Dopamine neurons are activated by rewarding events that are better than predicted, remain uninfluenced by events that are as good as predicted, and are depressed by events that are worse than predicted. By signaling rewards according to a prediction error, dopamine responses have the formal characteristics of a teaching signal postulated by reinforcement learning theories. Dopamine responses transfer during learning from primary rewards to reward-predicting stimuli. This may contribute to neuronal mechanisms underlying the retrograde action of rewards, one of the main puzzles in reinforcement learning. The impulse response releases a short pulse of dopamine onto many dendrites, thus broadcasting a rather global reinforcement signal to postsynaptic neurons. This signal may improve approach behavior by providing advance reward information before the behavior occurs, and may contribute to learning by modifying synaptic transmission. The dopamine reward signal is supplemented by activity in neurons in striatum, frontal cortex, and amygdala, which process specific reward information but do not emit a global reward prediction error signal. A cooperation between the different reward signals may assure the use of specific rewards for selectively reinforcing behaviors. Among the other projection systems, noradrenaline neurons predominantly serve attentional mechanisms and nucleus basalis neurons code rewards heterogeneously. Cerebellar climbing fibers signal errors in motor performance or errors in the prediction of aversive events to cerebellar Purkinje cells. Most deficits following dopamine-depleting lesions are not easily explained by a defective reward signal but may reflect the absence of a general enabling function of tonic levels of extracellular dopamine. Thus dopamine systems may have two functions, the phasic transmission of reward information and the tonic enabling of postsynaptic neurons.
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Lattanzio, Matthew S. "Delayed escape responses of male Basiliscus plumifrons (Squamata: Corytophanidae) during peak activity." Phyllomedusa: Journal of Herpetology 18, no. 2 (December 17, 2019): 185–93. http://dx.doi.org/10.11606/issn.2316-9079.v18i2p185-193.
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Delayed escape responses of male Basiliscus plumifrons (Squamata: Corytophanidae) during peak activity. Many animals must balance their time spent active in a habitat against their perceived risk of predation. Factors that may increase that perceived risk, such as a faster predator approach, are therefore expected to cause prey to initiate escape quickly to avoid capture. At the same time, because patterns of daily activity can fuctuate throughout the day, the relative costs and benefts of initiating escape may also differ over time. Here I evaluated the escape responses of adult male emerald basilisk (Basiliscus plumifrons) lizards in two different time periods: morning (when daily activity peaks) and early afternoon (when activity is suppressed). Further, I approached each lizard at either a practiced slow or fast pace. Escape responses were recorded as fight-initiation (distance between observer and lizard prior to escape) and fight (distance travelled during escape) distance. No factor affected fight distance, and approach speed also had no effect on fight initiation distance. In contrast, time period affected fight initiation distance, with males approached in the morning delaying their escape response compared to males approached during the early afternoon. Because morning and early afternoon periods coincide with peak and suppressed periods of activity for basilisks at this study site, respectively, ambushforaging species like B. plumifrons may delay escape when active to avoid prematurely alerting the predator of their presence.
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Kobayashi, Leo, John W. Gosbee, and Derek L. Merck. "Development and Application of a Clinical Microsystem Simulation Methodology for Human Factors-Based Research of Alarm Fatigue." HERD: Health Environments Research & Design Journal 10, no. 4 (November 3, 2016): 91–104. http://dx.doi.org/10.1177/1937586716673829.
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Objectives: (1) To develop a clinical microsystem simulation methodology for alarm fatigue research with a human factors engineering (HFE) assessment framework and (2) to explore its application to the comparative examination of different approaches to patient monitoring and provider notification. Background: Problems with the design, implementation, and real-world use of patient monitoring systems result in alarm fatigue. A multidisciplinary team is developing an open-source tool kit to promote bedside informatics research and mitigate alarm fatigue. Method: Simulation, HFE, and computer science experts created a novel simulation methodology to study alarm fatigue. Featuring multiple interconnected simulated patient scenarios with scripted timeline, “distractor” patient care tasks, and triggered true and false alarms, the methodology incorporated objective metrics to assess provider and system performance. Developed materials were implemented during institutional review board–approved study sessions that assessed and compared an experimental multiparametric alerting system with a standard monitor telemetry system for subject response, use characteristics, and end-user feedback. Results: A four-patient simulation setup featuring objective metrics for participant task-related performance and response to alarms was developed along with accompanying structured HFE assessment (questionnaire and interview) for monitor systems use testing. Two pilot and four study sessions with individual nurse subjects elicited true alarm and false alarm responses (including diversion from assigned tasks) as well as nonresponses to true alarms. In-simulation observation and subject questionnaires were used to test the experimental system’s approach to suppressing false alarms and alerting providers. Conclusions: A novel investigative methodology applied simulation and HFE techniques to replicate and study alarm fatigue in controlled settings for systems assessment and experimental research purposes.
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Preissner, Klaus T., and Heiko Herwald. "Extracellular nucleic acids in immunity and cardiovascular responses: between alert and disease." Thrombosis and Haemostasis 117, no. 07 (2017): 1272–82. http://dx.doi.org/10.1160/th-16-11-0858.
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SummarySevere inflammatory complications are a potential consequence in patients with predetermined conditions of infections, pulmonary diseases, or cardiovascular disorders. Notably, the amplitude of the inflammatory response towards these complications can dictate the disease progression and outcome. During the recent years, evidence from basic research as well as from clinical studies has identified self-extracellular nucleic acids as important players in the crosstalk between immunity and cardiovascular diseases. These stress- or injury-induced endogenous polymeric macromolecules not only serve as “alarmins” or “Danger-associated molecular patterns” (DAMPs), but their functional repertoire goes far beyond such activities in innate immunity. In fact, (patho-) physiological functions of self-extracellular DNA and RNA are associated and in many cases causally related to arterial and venous thrombosis, atherosclerosis, ischemia-reperfusion injury or tumour progression. Yet, the underlying molecular mechanisms are far from being completely understood. Interestingly enough, however, novel antagonistic approaches in vitro and in vivo, particularly using natural endonucleases or synthetic nucleic acid binding polymers, appear to be promising and safe therapeutic options for future studies. The aim of this review article is to provide an overview of the current state of (patho-) physiological functions of self-extracellular nucleic acids with special emphasis on their role as beneficial / alerting or adverse / damaging factors in connection with immune responses, inflammation, thrombosis, and cardiovascular diseases.
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Blessing, William Walter. "Clozapine increases cutaneous blood flow and reduces sympathetic cutaneous vasomotor alerting responses (SCVARs) in rats: comparison with effects of haloperidol." Psychopharmacology 181, no. 3 (June 29, 2005): 518–28. http://dx.doi.org/10.1007/s00213-005-0012-9.
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Schlender, Jörg, Veit Hornung, Stefan Finke, Margit Günthner-Biller, Sabrina Marozin, Krzysztof Brzózka, Sharareh Moghim, Stefan Endres, Gunther Hartmann, and Karl-Klaus Conzelmann. "Inhibition of Toll-Like Receptor 7- and 9-Mediated Alpha/Beta Interferon Production in Human Plasmacytoid Dendritic Cells by Respiratory Syncytial Virus and Measles Virus." Journal of Virology 79, no. 9 (May 1, 2005): 5507–15. http://dx.doi.org/10.1128/jvi.79.9.5507-5515.2005.
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ABSTRACT Human plasmacytoid dendritic cells (PDC) are key sentinels alerting both innate and adaptive immune responses through production of huge amounts of alpha/beta interferon (IFN). IFN induction in PDC is triggered by outside-in signal transduction pathways through Toll-like receptor 7 (TLR7) and TLR9 as well as by recognition of cytosolic virus-specific patterns. TLR7 and TLR9 ligands include single-stranded RNA and CpG-rich DNA, respectively, as well as synthetic derivatives thereof which are being evaluated as therapeutic immune modulators promoting Th1 immune responses. Here, we identify the first viruses able to block IFN production by PDC. Both TLR-dependent and -independent IFN responses are abolished in human PDC infected with clinical isolates of respiratory syncytial virus (RSV), RSV strain A2, and measles virus Schwarz, in contrast to RSV strain Long, which we previously identified as a potent IFN inducer in human PDC (Hornung et al., J. Immunol. 173:5935-5943, 2004). Notably, IFN synthesis of PDC activated by the TLR7 and TLR9 agonists resiquimod (R848) and CpG oligodeoxynucleotide 2216 is switched off by subsequent infection by RSV A2 and measles virus. The capacity of RSV and measles virus of human PDC to shut down IFN production should contribute to the characteristic features of these viruses, such as Th2-biased immune pathology, immune suppression, and superinfection.
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Dotare, Masashi, Michel Bader, Sarah K. Mesrobian, Yoshiyuki Asai, Alessandro E. P. Villa, and Alessandra Lintas. "Attention Networks in ADHD Adults after Working Memory Training with a Dual n-Back Task." Brain Sciences 10, no. 10 (October 8, 2020): 715. http://dx.doi.org/10.3390/brainsci10100715.
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Patients affected by Attention-Deficit/Hyperactivity Disorder (ADHD) are characterized by impaired executive functioning and/or attention deficits. Our study aim is to determine whether the outcomes measured by the Attention Network Task (ANT), i.e., the reaction times (RTs) to specific target and cue conditions and alerting, orienting, and conflict (or executive control) effects are affected by cognitive training with a Dual n-back task. We considered three groups of young adult participants: ADHD patients without medication (ADHD), ADHD with medication (MADHD), and age/education-matched controls. Working memory training consisted of a daily practice of 20 blocks of Dual n-back task (approximately 30 min per day) for 20 days within one month. Participants of each group were randomly assigned into two subgroups, the first one with an adaptive mode of difficulty (adaptive training), while the second was blocked at the level 1 during the whole training phase (1-back task, baseline training). Alerting and orienting effects were not modified by working memory training. The dimensional analysis showed that after baseline training, the lesser the severity of the hyperactive-impulsive symptoms, the larger the improvement of reaction times on trials with high executive control/conflict demand (i.e., what is called Conflict Effect), irrespective of the participants’ group. In the categorical analysis, we observed the improvement in such Conflict Effect after the adaptive training in adult ADHD patients irrespective of their medication, but not in controls. The ex-Gaussian analysis of RT and RT variability showed that the improvement in the Conflict Effect correlated with a decrease in the proportion of extreme slow responses. The Dual n-back task in the adaptive mode offers as a promising candidate for a cognitive remediation of adult ADHD patients without pharmaceutical medication.
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Ringo, J. L., and S. G. O'Neill. "Indirect inputs to ventral temporal cortex of monkey: the influence of unit activity of alerting auditory input, interhemispheric subcortical visual input, reward, and the behavioral response." Journal of Neurophysiology 70, no. 6 (December 1, 1993): 2215–25. http://dx.doi.org/10.1152/jn.1993.70.6.2215.
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1. This study examined nonvisual and indirect inputs to 1,021 single units recorded in inferotemporal and parahippocampal cortex of behaving macaques. 2. To better isolate these influences, a fully split-brain, split-chiasm preparation was used. Extracellular single-unit activity was recorded while the ipsilateral eye was covered. During the recordings the monkeys worked on a visual discrimination task that consisted of a series of presentations of single images. 3. When the interval between presentations was varied randomly (usually between 4 and 15 s) about one-quarter of these cells responded to an alerting tone sounded 500 ms before the onset of the visual image. That this response is due to the warning value of the tone was shown by finding that an identical tone sounded at the end of each trial produced no response from these cells. Use of an exchange between pairs of light-emitting diodes as a warning signal (one turned on as the other was turned off, also 500 ms before the visual stimulus onset) produced a similar response in many units. This indicates a subcortical route for the alerting signal. In most cases, warning responses were inhibitory, often delayed with respect to the warning signal occurrence to more nearly match the image arrival time. 4. Surprisingly, and despite the monkeys' confirmed split-brain status, occasional cells (approximately 2%) showed a response from a visual presentation limited to the other hemisphere. Although this subcortical visual input was far weaker than direct visual input, it was nonetheless statistically reliable. Importantly, the indirect input was stimulus specific and could form the neural basis for a limited interhemispheric visual transfer of the sort seen in human split-brain patients. 5. Also rarely, cells showed activity time locked to the animal's behavioral response.
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Gianna-Poulin, Claire C., and Robert J. Peterka. "Use of a visual guide to improve the quality of VOR responses evoked by high-velocity rotational stimuli." Journal of Vestibular Research 18, no. 1 (July 1, 2008): 15–24. http://dx.doi.org/10.3233/ves-2008-18102.
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High-velocity rotational stimuli have the potential to improve the diagnostic capabilities of clinical rotation testing by revealing nonlinear vestibulo-ocular reflex (VOR) responses that are indicative of asymmetric vestibular function. However, eye movements evoked by high-velocity rotations often are inconsistent over time and therefore do not yield reliable diagnostic measures. This study investigated whether use of a novel "visual guide" could improve the consistency and quality of VORs obtained during testing with pulse-step-sine (PSS) stimuli providing periodic high-velocity, horizontal-plane rotations with peak velocities up to 290 deg/s. The visual guide (narrow phosphorescent line spanning 180° field of view) was mounted horizontally on the rotation chair at the subject's eye level. Eight healthy human subjects were tested either in complete darkness while performing an alerting task, or while viewing the visual guide in an otherwise dark room. We found that the visual guide improved the quality of VOR responses as shown by an increased proportion of slow-phase velocity data segments retained for analysis, by a decreased variance of the processed eye velocity data, and by a reduction of outlying VOR response measures. We also found that the visual guide did not induce visual suppression because VOR gain measures were not diminished.