Dissertations / Theses on the topic 'Short-term memory Age Factors'

Two studies, involving a total of 184 adults between 17 and 89 years of age, were conducted to determine whether age differences in skill acquisition and transfer could be related to age differences in working memory functioning and anxiety. In both experiments, working memory functioning was measured using the Digit Span task (Wechsler, 1997) und the Reading Span tusk (Daneman & Carpenter, 1980), while anxiety levels were measured using the State Trait Anxiety Inventory (Spielberger, Gorsuch, Lushene, Vagg, & Jacobs, 1983). Participants were required to perform a mental arithmetic task in Experiment I, and a visual numerosity task in Experiment 2. In each experiment, participants received 240 trials of the task during u training phase (in which one set of stimuli were used) and 240 trials during a transfer phase (in which a second set of stimuli were used). The results from both studies revealed that partial positive transfer occurred from one phase to another for both young and older adults. This indicates that both age groups learned the skills in a similar way: using a combination of general und specific learning, Moreover, the older adults in both experiments became faster with practice, they generally improved as much as younger adults with practice, and they were able to achieve the same or better levels of accuracy compared to younger adults, This suggests that healthy older adults possess the ability to learn new skills. When scores for working memory span and anxiety were analysed, working memory span was found to correlate significantly with the accuracy levels and reaction times of the young age group in Experiment l, and of both age groups in Experiment 2. Similarly, anxiety levels were related to reaction times for both age groups in both experiments, with higher levels of anxiety also associated with smaller working memory spans for the young adults in both experiments. These results suggest that both working memory span and anxiety hove an impact on the performance of participants, and can account for some of the age differences observed during skill acquisition and transfer.

The purposes of the present study were to investigate the relationship between short-term memory and reading in learning disabled and average learners, and to determine whether this relationship is different between ages 8 to 10 and ages 11 to 13 in these two populations. Studies have shown that children with learning disabilities tend to perform poorer on short-term memory tasks compared to children with no disabilities. The present study was conducted because the short-term memory component in the Stanford-Binet Intelligence Scale is new and it was felt that information regarding this test's usefulness with learning disabled students would be beneficial for individuals in the field of educational assessment. A total of 80 children, 39 average and 41 learning disabled were selected from the five public elementary schools that have learning disabilities classes in the Langley School District. For each group of learning disabled children selected from the learning disabilities class, an equal number of average learners was chosen from the same school. The children were divided into two age groups: 8- to 10-year-olds and 11- to 13-year-olds and then further divided into their two learning categories. Four short-term memory subtests of the Stanford-Binet Intelligence Scale: Fourth Edition: Bead Memory, Memory for Sentences, Memory for Digits and Memory for Objects and three reading comprehension subtests, from B.C. QUick Individual Educational Test, Peabody Individual Achievement Test and Test of Reading Comprehension respectively, were administered to all groups to measure short-term memory and reading. The Multivariate Analysis of Variance and the Pearson Product-Moment Correlation were used to analyse the data. Results showed that the average learners scored significantly higher than the learning disabled group in both short-term memory and reading. There was no interaction effect of learning group and age on reading or short-term memory. Significant relationships were found between short-term mmeory and reading for the average learning group but none was found for the learning disabled group.
Education, Faculty of
Graduate

There are long-standing but ongoing debates in the literature about the composition of memory and the causes of short-term forgetting. Some researchers believe human memory is a dual system that comprises separate stores for verbal short-term memory (STM) and long-term memory (LTM), best exemplified by Baddeley and Hitch’s (1974) Working Memory Model. Dual memory researchers also believe that information stored in verbal STM decays over time if it is not refreshed through engaging in some form of covert rehearsal. However, other researchers believe verbal STM and LTM are intrinsically related, with short-term forgetting resulting from some level of interference that disrupts encoding the newly acquired information into verbal STM. The literature has indicated that the Working Memory Model could explain some but not all of the effects in verbal STM. In addition, while information degrades from verbal STM, it is not entirely lost and individuals use their LTM to assist with short-term recall. Moreover, researchers have found that decay does not explain all short-term forgetting and that interference does cause short-term forgetting. This thesis examined the unitary view of human memory by investigating the redintegration explanation for short-term recall, whereby individuals access long-term knowledge to aid in the reconstruction of degraded phonological memory traces for later recall. Redintegration emphasises that verbal STM and LTM work in unison to help individuals retrieve information for later recall. The three studies comprising this thesis examined the predictions of redintegration in relation to short-term recall and age differences by varying the difficulty level of the memory task. All studies operationalised task difficulty by manipulating the combination of recall intervals (immediate vs. delayed), study conditions (silence vs. irrelevant speech), and presentation rates (one second vs. two seconds). Twenty young and 20 older adults were instructed to remember short lists of words across eight different memory conditions. In Study one, redintegration was measured using the word length effect (Baddeley, Thompson, & Buchanan, 1975) and findings showed that as task difficulty increased, recall was higher for short words because they had fewer segments to reassemble from LTM compared with long words. In Study two, redintegration was measured using associate word pairs and findings showed that as task difficulty increased, recall was higher for words in the associate pairs because participants used the semantic relationships in LTM as additional retrieval cues to reconstruct the short-term phonological traces that rapidly dissipated during encoding. In Study three, redintegration was measured using the false memory effect (Roediger III & McDermott, 1995) and findings showed that as task difficulty increased, recall was higher for words related to a non-presented critical lure words because participants used the relatedness among the words along with the critical lure as additional retrieval cues to search LTM and reconstruct the degraded short-term phonological traces. For all studies, there were no significant age differences in redintegration, suggesting that young and older adults engage in the same process by using long-term information to rebuild the rapidly dissipating phonological memory traces for short-term recall and use additional retrieval cues to enhance the redintegration process. Collectively, these findings provide support for the redintegration process that emphasises the intrinsic relationship between verbal STM and LTM. When short- term recall became difficult, young and older adults effectively cued the search for long-term information to facilitate the redintegration process and aid short-term recall. This thesis also substantiated the interference view on short-term forgetting, where increasing task difficulty increased the reliance on redintegration to improve verbal STM performance.

The ageing literature shows robust age-related declines in immediate (e.g. Bopp & Verhaeghen, 2005; Multhaup, Balota & Cowan, 1996; Verhaeghen, 2002; Verhaeghen, Marcoen & Goosens, 1993) and episodic memory (Fleischman, Wilson, Gabrieli, Bienias & Bennett, 2004; Park, 2000; Schaie, 2005; Singer, Lindenberger & Baltes, 2003). However, older adults also consistently show stable or even improving levels of semantic knowledge (Surprenant & Neath, 2007). In younger adults, Hemmer and Steyvers (2009) showed that episodic memory for the properties (i.e. size) of familiar items is influenced by multiple levels of pre-existing knowledge. In this thesis, I developed their paradigm to systematically explore these knowledge effects in healthy ageing for both episodic memory and short-term/ immediate memory. This was done by comparing memory for familiar relative to unfamiliar faces, as well as for the size of familiar everyday objects relative to unfamiliar, random shapes. Across all experiments, both age groups appeared to rely on pre-existing item-based knowledge for the familiar items to the same extent, suggesting no age-related decrement in the use of prior knowledge. Moreover, the result showed that item-specific knowledge for the unfamiliar items develops over the course of the experiment. This became apparent in cases when the distribution of target item sizes was bimodal, as this made session-based learning of the item statistics easier to observe; this experiment-based knowledge/ learning was again equivalent for both age groups. The older adults, however, consistently demonstrated greater reconstruction variability and overall error. I interpreted this as evidence of noisier memory representations of the studied items for the older adults (e.g. Noack, Lovden & Lindenberger, 2014); the findings suggest that this increase in error does not lead to more knowledge-based bias in older adults.

Thesis (Ph. D.)--West Virginia University, 1998.
Title from document title page. Document formatted into pages; contains iii, 89 p. Vita. Includes abstract. Includes bibliographical references (p. 65-82).

The nature of the rehearsal mechanism that supports short-term memory span (STM), and the role of lexical and semantic knowledge in list recall was evaluated. Forty university students (aged 17-29 years) recalled lists of words varied in syllable-length (SL), articulatory duration (AD), phonological similarity (PS), semantic relatedness (SR) and frequency of occurrence (FO). Auditory and visual presentation, vocal and picture-pointing recall, and concurrent articulation conditions were included. Nonword recall was evaluated using stimuli varied in SL and PS was also evaluated using a repetition task. Word length effects were found for word stimuli varied in SL but were absent or reversed for stimuli varied in AD. A non-articulatory basis for rehearsal is suggested. The influence of long-term semantic and lexical knowledge in recall is inconclusive due to a lack of SR. Nonword repetition ability reflects STM capacity in adult subjects and correlates with other measures of STM span.

Thesis (M.A.)--University of North Carolina at Chapel Hill, 2007.
Title from electronic title page (viewed Dec. 18, 2007). "... in partial fulfillment of the requirements for the degree of Master of Arts in the Department of Psychology (Cognitive)." Discipline: Psychology; Department/School: Psychology.

The current study investigated the effects of aging on the strategic control of attention at encoding and the extent to which this relationship was mediated by working memory capacity. The value-directed remembering task used by Castel et al. (2009) was modified to include an inhibitory task demand (i.e., value-directed forgetting), and age differences were predicted due to declines in the efficiency of inhibitory mechanisms. Results confirmed this prediction, as older adults were less efficient in maximizing their selectivity scores upon the inclusion of task interference, and working memory was found to be supportive of performance. Results additionally support an age-related decline in the directed forgetting effect, such that older adults recalled and recognized fewer TBR items and more TBF items, relative to younger adults. Taken together, results suggest an age-related decline in the ability to inhibit goal-irrelevant information, thereby limiting working memory resources available for greater processing of goal-relevant information.

A particular field in research on judgment and decision making (JDM) is concerned with realism of confidence in one’s knowledge. An interesting finding is the so-called format dependence effect, which implies that assessment of the same probability distribution generates different conclusions about over- or underconfidence depending on the assessment format. In particular, expressing a belief about some unknown continuous quantity (e.g., a stock value) in the form of an intuitive confidence interval is severely prone to overconfidence as compared to expressing the belief as an assessment of a probability judgment. This thesis gives a tentative account of this finding in terms of a Naïve Sampling Model, which assumes that people accurately describe their available information stored in memory, but they are naïve in the sense that they treat sample properties as proper estimators of population properties (Study 1). The effect of this naivety is directly investigated empirically in Study 2. A prediction that short-term memory is a constraining factor for sample size in judgment, suggesting that experience per se does not eliminate overconfidence is investigated and verified in Study 3. Age-related increments in overconfidence were observed with intuitive confidence interval but not for probability judgment (Study 4). This thesis suggests that no cognitive processing bias (e.g., Tversky & Kahneman, 1974) over and above naivety is needed to understand and explain the overconfidence “bias” with intuitive confidence interval and hence the format dependence effect.

Thesis (Ph. D.)--Psychology, Georgia Institute of Technology, 2008.
Fischer, U., Committee Member ; Fisk, A. D., Committee Member ; Catrambone, R., Committee Member ; Engle, Randall W., Committee Member ; Rogers, Wendy A., Committee Chair.

BackgroundThe prompt seeking of medical care after the onset of symptoms suggestive of acute coronary syndromes (ACS)/acute myocardial infarction (AMI) is associated with the receipt of coronary reperfusion therapy, and effective cardiac medications in patients with an ACS/AMI and is crucial to reducing mortality and the risk of serious clinical complications in these patients. Despite declines in important hospital complications and short-term death rates in patients hospitalized with an ACS/AMI, several patient groups remain at increased risk for these adverse outcomes, including women and the elderly. However, recent trends in age and sex differences in extent of pre-hospital delay, hospital management practices, and short-term outcomes associated with ACS/AMI remain unexplored. The objectives of this study were to examine the overall magnitude, and changing trends therein, of age and sex differences in duration of pre-hospital delay (1986-2005), hospital management practices (1999-2007), and short-terms outcomes (1975-2005) in patients hospitalized with ACS/AMI. MethodsData from 13,663 residents of the Worcester, MA, metropolitan area hospitalized at all greater Worcester medical centers for AMI 15 biennial periods between 1975 and 2005 (Worcester Heart Attack Study), and from 50,096 patients hospitalized with an ACS in 106 medical centers in 14 countries participating in the Global Registry of Acute Coronary Events (GRACE) between 2000 and 2007 were used for this investigation. Results In comparison with men years, patients in other age-sex strata exhibited significantly longer pre-hospital delay, with the exception of women < 65 years; had a significantly lower odds of receiving aspirin, angiotensin converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs), beta blockers, statins, and undergoing coronary artery bypass graft surgery (CABG) surgery or percutaneous coronary intervention (PCI), and were significantly more likely to develop atrial fibrillation, cardiogenic shock, heart failure, and to die during hospitalization and in the first 30 days after admission. There was a significant interaction between age and sex in relation to the use of several medications and the development of several of these outcomes; in patients Conclusions Our results suggest that the elderly were more likely to experience longer prehospital delay, were less likely to be treated with evidence-based treatments during hospitalization for acute coronary syndrome, and were more likely to develop adverse outcomes compared to younger persons. Younger women were less likely to be treated with effective treatments and were more likely to develop adverse outcomes compared with younger men while there was no sex difference in these outcomes. Interventions targeted at older patients, in particular, are needed to encourage these high-risk patients to seek medical care promptly to maximize the benefits of currently available treatment modalities. More targeted treatment approaches during hospitalization for ACS/AMI for younger women and older patients are needed to improve their hospital prognosis.

Táto diplomová práca sa venuje automatickému rozpoznávaniu ludí v obrazových dátach s využitím konvolučných neurónových sieti na určenie polohy tváre a následnej analýze získaných dát. Výsledkom analýzy tváre je určenie pohlavia, emócie a veku osoby. Práca obsahuje popis použitých architektúr konvolučných sietí pre každú podúlohu. Sieť na odhad veku má natrénované nové váhy, ktoré sú vzápätí zmrazené a majú do svojej architektúry vložené LSTM vrstvy. Tieto vrstvy sú samostatne dotrénované a testované na novom datasete vytvorenom pre tento účel. Výsledky testov ukazujú zlepšenie predikcie veku. Riešenie pre rýchlu, robustnú a modulárnu detekciu tváre a ďalších ludských rysov z jedného obrazu alebo videa je prezentované ako kombinácia prepojených konvolučných sietí. Tieto sú implementované v podobe skriptu a následne vysvetlené. Ich rýchlosť je dostatočná pre ďalšie dodatočné analýzy tváre na živých obrazových dátach.

Le pemphigus est une maladie auto-immune spécifique de la peau et des muqueuses provoqué par des auto-anticorps (Ac) spécifiques des desmogléines (Dsg) 1 ou 3. Ces Ac pathogéniques inhibent l'adhésion cellulaire des kératinocytes. Le pemphigus se déclenche par la conjonction d’événements rares impliquant l’émergence puis la coopération de lymphocytes B (LB) et de lymphocytes LT auto-réactifs dans un contexte génétique et environnemental particulier. Jusqu’à présent, la première ligne de traitement du pemphigus était constituée de fortes doses de corticoïdes, qui sont de puissants immunosupresseurs systèmiques. Le Rituximab (RTX), un Ac monoclonal chimérique anti-CD20, constitue une thérapeutique innovante aboutissant à l’élimination des LB. L’étude clinique RITUX 3 a été conçue pour évaluer l’efficacité et l’innocuité du traitement utilisant le RTX associé à une courte corticothérapie dans le traitement de première intention du pemphigus par rapport au traitement de référence par la corticothérapie standard (CS). Dans un premier temps, notre analyse clinico-biologique des patients après 24 mois a démontré que l’utilisation du RTX associé à de la prednisone à court terme en traitement de première intention chez les patients atteints de pemphigus foliacé et vulgaire modéré à sévère est à la fois plus efficace et mieux toléré que le traitement de référence par la prednisone seule (89% de patients versus 34%). Cette efficacité a été confortée à plus long terme après la reconstitution du répertoire lymphocytaire B avec un risque de rechute de 2% à 36 mois. La présence d’une forme sévère de pemphigus au diagnostic (PDAI ≥ 45) et d’un taux d’Ac anti-Dsg à 3 mois supérieur aux valeurs seuils (anti-Dsg1 ≥ 20 ou anti-Dsg3 ≥ 120) sont associés à un risque de rechute précoce de 50%. Ces deux facteurs prédictifs permettent d'identifier un sous-groupe de patients présentant un risque élevé de rechute nécessitant une perfusion d'entretien de RTX au 6ème mois. Dans un deuxième temps, nous avons étudié l’impact des traitements par RTX et par CS chez les patients atteints de pemphigus afin de mieux appréhender la réponse auto-immune. La caractérisation phénotypique des LB auto-réactifs et l’analyse de la fréquence des LB capables de sécréter des immunoglobulines (Ig)G anti-Dsg par une approche ELISPOT a permis d’établir que l’efficacité du traitement par RTX dans le pemphigus semble liée à l’élimination des LB mémoires CD27+IgG+ spécifiques des Dsg. Des LB auto-réactifs Dsg restent détectables après RTX suite à la reconstitution lymphocytaire B, mais ces LB ont un phénotype naïf et non commuté (IgM) et ne secrètent plus d’IgG. En revanche, la persistance des LB auto-réactifs capables de sécréter des IgG anti-Dsg après traitement par CS est certainement à l’origine des rechutes fréquentes. L’analyse de l’expression génique ciblée à l’échelle unicellulaire a démontré qu’initialement, les LB spécifiques des Dsg ont un profil pro-inflammatoire avec l’expression de trois gènes codant pour les interleukines (IL)-1β, IL-12p35 et IL-23p19 et pour le gène de l’IRF5 (Interferon regulatory factor 5) par rapport aux LB non auto-réactifs. Le RTX et la CS ont des effets différents sur l'expression de ces gènes mais les deux réduisent l’expression génique d’IL-1β qui semble jouer un rôle important dans la physiopathologie du pemphigus. Parallèlement, l’analyse transcriptomique puis protéique des LB isolés des patients en rémission complète ou incomplète 6 ans après l’étude RITUX 1 a mis en évidence une augmentation d'expression de KCNN4 (Potassium calcium-activated channel subfamily N member 4) à la surface des LB chez les patients atteints de pemphigus en rémission complète pouvant influencer la maturation des LB
Pemphigus is an autoimmune disease of the skin and mucous membranes caused by autoantibodies (Ab) specific to desmoglein (Dsg) 1 or 3. These pathogenic Ab inhibit cell adhesion of keratinocytes. The development of pemphigus is associated with the conjunction of many uncommon events involving the emergence and then the cooperation of auto-reactive B cells and T cells link to genetic and environmental factors. Until now, the first line of treatment consisted of high doses of corticosteroids. Rituximab (RTX), an anti-CD20 chimeric monoclonal antibody, is an innovative therapy that results in B cells depletion. The RITUX 3 clinical trial was designed to evaluate the efficacy and safety of RTX combined with a short-course glucocorticoid therapy as a first-line treatment of pemphigus versus the standard treatment with standard corticosteroids (CS). As a first step, our clinico-biological analysis of patients after 24 months has shown that the use of RTX combined with short-term prednisone as a first-line treatment in patients with moderate to severe pemphigus is both more effective and better tolerated than the reference treatment with prednisone alone. Respectively, 89% of patients versus 34% in each group and both pemphigus foliaceus and pemphigus vulgaris patients responded. This efficacy was confirmed in the longer term after reconstitution of the B lymphocyte repertoire with a risk of relapse of only 2% at 36 months. The presence of a severe form of pemphigus at diagnosis (PDAI ≥ 45) and an anti-Dsg Ab level at 3 months above threshold values (anti-DSG1 ≥ 20 or anti-DSG3 ≥ 120) are associated with 50% risk of early relapse. These two predictive factors make it possible to identify a subgroup of patients at high risk of relapse requiring a maintenance infusion of RTX at the 6th month. In a second step, we studied the impact of RTX and CS treatments in patients with pemphigus in order to better understand the autoimmune response. The phenotypic characterization of auto-reactive B cells and the analysis of the frequency of B cells able of secreting anti-Dsg immunoglobulin (Ig) G by an ELISPOT approach demonstrated that the efficacy of RTX treatment in pemphigus seems related to the elimination of IgG-switched Dsg memory B-cells. Dsg specific B cells remain detectable after RTX when B cells return, but these B cells have a naïve and non-switched (IgM) phenotype and no longer secrete IgG. On the other hand, the persistence of self-reactive Dsg B cells capable of secreting IgG anti-Dsg after treatment with CS is certainly at the origin of the frequency of relapses. The unicellular targeted gene expression analysis demonstrated that initially, Dsg-specific B cells have a pro-inflammatory profile with the overexpression of three genes encoding Interleukin (IL) -1β, IL-12p35 and IL-23p19 and for the IRF5 gene (Interferon regulatory factor 5) compared to non-self-reactive B cells. RTX and CS have different effects on the expression of these genes, but both reduce the gene expression of IL-1β, which seems to play an important role in the pathophysiology of pemphigus

Charakterystyka problemu: Wraz z wiekiem sprawność wielu funkcji poznawczych ulega pogorszeniu, utrudniając efektywną adaptację do wymogów środowiska. Biorąc pod uwagę starzenie się społeczeństwa, badania nad mechanizmami leżącymi u podłoża zachodzących zmian są niezwykle istotne. Szczególnie ważna w tym kontekście wydaje się być tematyka zniekształceń w pamięci krótkotrwałej, kluczowej dla efektywnego funkcjonowania człowieka. W odniesieniu do pamięci długotrwałej starsi dorośli, w porównaniu do grupy młodszych dorosłych, dokonują większej ilości fałszywych rozpoznań oraz są bardziej przekonani o poprawności swoich odpowiedzi. Różnice te związane są m.in. ze zmianami w funkcjonowaniu hipokampa oraz okolic czołowych. Wiadomo także, że fałszywe rozpoznania pojawiają się już parę sekund od momentu zakodowania informacji, jednak wiedza dotycząca wpływu różnic związanych z wiekiem na tego typu zniekształcenia jest ograniczona. W szczególności brakuje badań uwzględniających pewność towarzyszącą odpowiedziom oraz dotyczących mechanizmów neuronalnych leżące u podłoża tych różnic. Cel badań: Niniejsza rozprawa doktorska dotyczy zniekształceń we wzrokowej pamięci krótkotrwałej u starszych i młodszych dorosłych. Jej celem była analiza związanych z wiekiem różnic w charakterystyce fałszywych rozpoznań oraz w mechanizmach neuronalnych leżących u ich podłoża. Pierwszym celem pracy było określenie i porównanie poziomu wykonania zadania eksperymentalnego przez starszych i młodszych dorosłych, w tym ilości fałszywych rozpoznań wynikających z podobieństwa fizycznego bodźca i próby pamięciowej, a także różnic w pewności odpowiedzi. Drugim celem pracy było określenie neuronalnych mechanizmów leżących u podłoża obserwowanych różnic, w oparciu o dane uzyskane z zastosowaniem techniki funkcjonalnego rezonansu magnetycznego (ang. functional magnetic resonance imaging, fMRI). Metody: W badaniu zastosowana została opracowana na użytek pracy procedura eksperymentalna, spełniająca założenia testów rozpoznania ze swobodnym wyborem, typu "taki sam-inny" (ang. same-different recognition task), przeprowadzonych z jednoczesnym pomiarem subiektywnego poziomu pewności określanego po każdej odpowiedzi. Jako materiał eksperymentalny wykorzystano bodźce abstrakcyjne. W pierwszym etapie przeprowadzone zostało badanie behawioralne na grupie 33 młodszych dorosłych (M 21.4, SD 1.84) i 33 starszych dorosłych (M 60.2 SD 4.54). Następnie, badanie fMRI z wykorzystaniem skanera MR Siemens Skyra 3T, w którym wzięło udział 25 młodszych dorosłych (M 24.2, SD 3.1) i 26 starszych dorosłych (M 65.5, SD 4.6). Wyniki: W żadnym z przeprowadzonych eksperymentów nie potwierdzono większej podatności starszych dorosłych na fałszywe rozpoznania podobnego wizualnie materiału po paru sekundach od jego zapamiętania. Wyniki wskazują jednak, iż, podobnie jak w przypadku pamięci długotrwałej, starsi dorośli są bardziej przekonani o poprawności swoich fałszywych rozpoznań. Wyniki badania fMRI wskazują m.in. na wzrost aktywności przedniego zakrętu obręczy i wieczka czołowego/kory wyspy podczas fałszywych rozpoznań dokonywanych przez młodszych dorosłych, sugerując wzmożoną ewaluację błędów i przetwarzanie niepewności. Podobny wzorzec nie został jednak zaobserwowany u starszych dorosłych. Porównanie aktywności mózgu starszych i młodszych dorosłych podczas fałszywych rozpoznań wskazuje na większą aktywność kory wzrokowej, przedniego zakrętu obręczy/środkowej części górnego zakrętu czołowego, wieczka czołowego/kory wyspy oraz okolic przednio‑bocznej kory przedczołowej oraz zakrętu czołowego środkowego u młodszych niż u starszych dorosłych. Dodatkowo, tylko aktywność kory wzrokowej jest modulowana niezależnie od umiejętności adekwatnej oceny pewności, tj. zdolności metapoznawczych osób badanych. Aktywność obszarów czołowych, a także kory wzrokowej, jest również związana z poziomem wykonania zadania. W szczególności, lepszy poziom wykonania koreluje ze wzmożoną aktywnością przedniego zakrętu obręczy. Wnioski: Podsumowując, uzyskane wyniki wskazują na związane z wiekiem różnice w ocenie pewności, ale nie w poprawności odpowiedzi we wzrokowej pamięci krótkotrwałej. Na poziomie neuronalnym wyniki wskazują natomiast na związane z wiekiem różnice w aktywności kory wzrokowej oraz licznych obszarach czołowych, sugerując związane z wiekiem zmiany w dostępnych reprezentacjach oraz, przede wszystkim, większą sprawność procesów monitorowania i kontroli u młodszych w porównaniu do starszych dorosłych. Projekt charakteryzuje nowatorskie ujęcie problematyki badawczej - do tej pory związane z wiekiem różnice w fałszywych rozpoznaniach i towarzyszącej im pewności były przedmiotem zainteresowania głównie w badaniach nad pamięcią długotrwałą. Niniejsza praca dostarcza natomiast informacji na niepoznany dotychczas temat związanych z wiekiem różnic w fałszywych rozpoznaniach w pamięci krótkotrwałej, ze szczególnym uwzględnieniem neuronalnego podłoża tych różnic. Praca otwiera zatem nowy kierunek badań w obszarze neuronauki dotyczącym tzw. starzenia się poznawczego. Dodatkowo, ponieważ istnieje niewiele badań dotyczących neuronalnych mechanizmów fałszywych rozpoznań w pamięci krótkotrwałej, niniejsza praca doktorska dostarcza także nowych informacji na temat specyfiki fałszywych rozpoznań we wzrokowej pamięci krótkotrwałej.
Background: Deficits in cognitive functioning become more robust with aging, impacting an individual's ability to adapt to the environment. Taking into account the ever-growing number of older adults in modern societies, research focused on the mechanisms underlying those changes is needed. In particular, considering the crucial role of short-term memory in everyday functioning, the importance of studies regarding age-related differences in this area is highlighted. In the context of episodic memory, older adults, compared to younger adults, are more susceptible to false memories and are more confident of these erroneous responses. These differences are related to senescent changes in the hippocampus and frontal lobe activity. It is known that false memories may occur within a few seconds after encoding, but the knowledge about the age-related differences therein is limited. In particular, there is a lack of research that takes into account the differences in the subjective level of confidence and in the neural mechanisms underlying short-term false recognitions. Objectives: The aim of this study was to analyze the age-related differences in false recognitions in the short-term memory, and in the neural mechanism underlying this phenomenon. The first goal of this work was to determine and compare the performance of younger and older adults, with regards to the rate of false recognitions of perceptually-related lures and the related confidence assessments. The second goal of this study was to identify the neural mechanisms of the observed age‑differences. Methods: The item based 'same'- 'different' recognition task, with following subjective confidence judgements and abstract objects used as targets, was developed to investigate the topic. Two experiments regarding false recognitions in the visual short-term memory were conducted - first a behavioral one, and then a neuroimaging one, with the use of functional magnetic resonance imaging technique (fMRI). Thirty-three younger adults (M 21.4, SD 1.84) and thirty-three older adults (M 60.2 SD 4.54) participated in the behavioral experiment. Next, the fMRI experiment was conducted in the 3T MR scanner Siemens Skyra. In this study twenty-five younger adults (M 24.2, SD 3.1) and twenty-six older adults (M 65.5, SD 4.6) participated. Results: The behavioral results of the two experiments did not provide evidence for older adults' greater susceptibility to false recognitions in an item-based visual short-term memory. However, they indicate that, similar to the long-term/episodic memory, older adults are more confident of their erroneous responses. The fMRI results indicated that in younger adults the activity of the anterior cingulate cortex and frontal operculum/insular cortex is higher during false recognitions, compared to correct rejections, suggesting an increased evaluation of errors and uncertainty. However, such pattern was not observed for older adults. The comparison of false alarms-related activity indicated the age-differences in activity of the visual cortex, the anterior cingulate cortex, the frontal operculum/insular cortex, and areas in the anterior prefrontal cortex and the medial frontal gyrus - the activity in these regions is higher in younger, compared to the older adults. In addition, only the differences in the visual cortex activity are independent of the individuals' metacognitive abilities. Also, an activity within both the frontal brain regions and the visual cortex is modulated by the individuals' performance. In particular, across both age groups better performance, measured by the sensitivity index, positively correlates with the activity of the anterior cingulate cortex. Conclusions: To conclude, the obtained results indicate the age-related differences in the subjective level of confidence following erroneous recognitions, but do not show the age-related differences in the rate of false memories in an item-based visual short-term memory task. At the neural level, the results indicate the age-related differences in the activity of the visual cortex and frontal areas, suggesting older adults' less detailed memory representations and the age-related changes in the involvement of monitoring and cognitive control processes. The conducted research is novel and adds a new insight into the mechanisms of false recognitions in short-term memory in younger and older adults. To date, older adults' susceptibility to highly confident false recognitions was studied in the context of long-term/episodic memory. The obtained results shed light on the age-related differences in false recognitions in the visual short-term memory, including the related differences in the neural activity. Thus, this research stands as a basis for a new direction in the field of the neurocognitive aging. In addition, as the knowledge about neural bases of short-term false memories is still scarce, the current study also provides new information on the mechanisms underlying this phenomenon in the visual short-term memory.

The aim of this thesis was to help elucidate the mechanisms that underlie age-related decline in visual selective attention and working memory (WM). Older and younger adults completed a behavioural WM task, after which electroencephalogram (EEG) was recorded as participants perform a localized attentional interference (LAI) task – competition/attentional interference was manipulated by systematically altering the distance between targets and distractors. Older adults showed impaired accuracy and reaction time on the WM and LAI tasks. Two event-related-potentials, indexing spatial attention (N2pc) and target processing (Ptc), displayed attenuated amplitude and increased latency in older adults. Thus, spatial selection, target enhancement and processing speed deficits may contribute to age-related attentional impairments. Furthermore, an unexpected component was found between the N2pc and Ptc in the older adult waveforms. Preliminary analyses suggest this may be the PD, implicated in distractor suppression, which may be differentially contributing to older and younger adults’ electrophysiology and attentional processing.

M.Tech (Homoeopathy)
The aim of this study is to determine the influence of homoeopathically prepared Ginkgo Biloba 6X potency compared with that of phytotherapeutically prepared Ginkgo Biloba Extract; on the results of psychometric tests used to ascertain short-term memory loss in the geriatric subject. 21 elderly volunteers received; Ginkgo Biloba Extract (500mg), a homoeopathic 6X potency of Ginkgo Biloba and a placebo according to a double blind design. One hour after administration of the treatment, volunteers were subjected to psychometric testing namely the Reading Comprehension Test, which serves to assess the status of the short-term memory. No statistically significant changes from the placebo were observed in either of the groups. Adjusted scores for education and Mini Mental Status Exam scores however revealed a positive trend in favour of the homoeopathic 6X potency of Ginkgo Biloba Further evaluation with a larger study sample could provide more conclusive evidence as to its efficacy