Articles de revues sur le sujet « Kanizsa illusion »

Visual illusion is the fallacious perception of reality or some actually existing object. In this paper, we imitate the mechanism of Ehrenstein illusion, neon color spreading illusion, watercolor illusion, Kanizsa illusion, shifted edges illusion, and hybrid image illusion using the Open Source Computer Vision Library (OpenCV). We also imitate these illusions using Cellular Neural Networks (CNNs). These imitations suggest that some illusions are processed by high-level brain functions. We next apply the morphological gradient operation to anomalous motion illusions. The processed images are classified into two kinds of images, which correspond to the central drift illusion and the peripheral drift illusion, respectively. It demonstrates that the contrast of the colors plays an important role in the anomalous motion illusion. We also imitate the anomalous motion illusions using both OpenCV and CNN. These imitations suggest that some visual illusions may be processed by the illusory movement of animations.

Every day, we experience a rich and complex visual world. Our brain constantly translates meaningless fragmented input into coherent objects and scenes. However, our attentional capabilities are limited, and we can only report the few items that we happen to attend to. So what happens to items that are not cognitively accessed? Do these remain fragmentary and meaningless? Or are they processed up to a level where perceptual inferences take place about image composition? To investigate this, we recorded brain activity using fMRI while participants viewed images containing a Kanizsa figure, an illusion in which an object is perceived by means of perceptual inference. Participants were presented with the Kanizsa figure and three matched nonillusory control figures while they were engaged in an attentionally demanding distractor task. After the task, one group of participants was unable to identify the Kanizsa figure in a forced-choice decision task; hence, they were “inattentionally blind.” A second group had no trouble identifying the Kanizsa figure. Interestingly, the neural signature that was unique to the processing of the Kanizsa figure was present in both groups. Moreover, within-subject multivoxel pattern analysis showed that the neural signature of unreported Kanizsa figures could be used to classify reported Kanizsa figures and that this cross-report classification worked better for the Kanizsa condition than for the control conditions. Together, these results suggest that stimuli that are not cognitively accessed are processed up to levels of perceptual interpretation.

The strength of the Poggendorff illusion has been determined by a nulling method for the classical as well as other configurations of the central inducing region. Compared to a uniform field, an inducing rectangle with very low contrast produces a marked illusion, which saturates at a Michelson contrast of about 0.1. With virtual borders of the Kanizsa type there is a weak illusion and this effect is attenuated when the ‘pacman’ sectors are occluded. Texture borders without luminance contrast induce a stronger illusion. These results are discussed in relation to earlier data for contrast dependence of Vernier acuity and for the orientation discrimination and tilt illusion with real and virtual borders.

An object phenomenally shrinks in its horizontal dimension when shown on a 2-D plane as if the central portion of the object were partially occluded by another vertical one in 3-D space (the Kanizsa amodal shrinkage). We examined the predictions of the correcting-mechanism hypothesis proposed by Ohtsuka and Ono (2002, Proceedings of SPIE4864 167 – 174), which states that an inappropriate operation of the mechanism that corrects a phenomenal increase in monocularly visible areas accompanied by a stereoscopic occluder gives rise to the illusion. In this study we measured the perceived width (or height in experiment 3) of a square seen behind a rectangle, while controlling other factors which potentially influence the illusion, such as the division of space or depth stratification. The results of five experiments showed that (a) the perceived width was not influenced when the occluder had a relatively large binocular disparity, but was underestimated when the occluder did not have disparity, and (b) the shrinkage diminished when the foreground rectangle was transparent, was horizontally oriented, or contained no pictorial occlusion cues. These results support the hypothesis that the correcting mechanism, triggered by pictorial occlusion cues, contributes to the Kanizsa shrinkage.

The study of illusory brightness and contour phenomena has become an important tool in modern brain research. Gestalt, cognitive, neural, and computational approaches are reviewed and their explanatory powers are discussed in the light of empirical data. Two well-known phenomena of illusory form are dealt with, the Ehrenstein illusion and the Kanizsa triangle. It is argued that the gap between the different levels of explanation, bottom—up versus top—down, creates scientific barriers which have all too often engendered unnecessary debate about who is right and who is wrong. In this review of the literature we favour an integrative approach to the question of how illusory form is derived from stimulus configurations which provide the visual system with seemingly incomplete information. The processes that can explain the emergence of these phenomena range from local feature detection to global strategies of perceptual organisation. These processes may be similar to those that help us restore partially occluded objects in everyday vision. To understand better the Ehrenstein and Kanizsa illusions, it is proposed that different levels of analysis and explanation are not mutually exclusive, but complementary. Theories of illusory contour and form perception must, therefore, take into account the underlying neurophysiological mechanisms and their possible interactions with cognitive and attentional processes.

Goldfish (Carassius auratus) were trained to discriminate triangles and squares using a two choice procedure. In the first experiment, three goldfish were trained with food reward on a black outline triangle on a white background, while a black outline square was shown for comparison. In transfer tests, a Kanizsa triangle and a Kanizsa square were presented, perceived by humans as an illusory triangle- or square-shaped surface of slightly higher brightness than the background. The choice behavior in this situation indicates that goldfish are able to discriminate between both figures in almost the same way as in the training situation. In control experiments goldfish did not discriminate between shapes in which humans do not perceive the illusion. A series of generalization experiments was performed indicating the similarity between the tested shapes and the training triangle. From all these findings we conclude that goldfish are able to perceive an illusory triangle or square within the Kanizsa figures. In a second experiment, four goldfish were trained on a white outline triangle versus a white outline square, both on black background with white diagonal lines. In transfer tests in which the shapes were replaced by gaps within the white diagonal lines, goldfish were clearly able to discriminate between the two patterns based on the illusory contours. This was not the case in tranfer tests with phase shifted abutting lines.

Westheimer, Gerald and Wu Li. Classifying illusory contours: edges defined by “pacman” and monocular tokens. J. Neurophysiol. 77: 731–736, 1997. Thresholds for the discrimination of orientation were measured in the human fovea for figures and borders delineated by solid lines and by “pacman” tokens as introduced by Kanizsa, as well as by contours induced by monocular tokens giving a stereoscopic depth illusion of a knife edge. Orientation discrimination of these illusory contours is poorer by a factor of ∼2 than that of equivalent contours made of solid lines and is not much better than that for their supporting structures if taken alone. It is concluded that these kinds of illusory borders do not address the “border” or “edge” mechanism in the same way as real lines. Orientation discrimination and simultaneous orientation contrast (tilt illusion) were compared for a variety of illusory borders. The more robust the borders, i.e., the more sensitive to changes in orientation, the less their susceptibility to the tilt illusion.

Visual illusions and perceptual grouping phenomena offer an invaluable tool for probing the computational mechanism of low-level visual processing. Some illusions, like the Kanizsa figure, reveal illusory contours that form edges collinear with the inducing stimulus. This kind of illusory contour has been modeled by neural network models by way of cells equipped with elongated spatial receptive fields designed to detect and complete the collinear alignment. There are, however, other illusory groupings which are not so easy to account for in neural network terms. The Ehrenstein illusion exhibits an illusory contour that forms a contour orthogonal to the stimulus instead of collinear with it. Other perceptual grouping effects reveal illusory contours that exhibit a sharp corner or vertex, and still others take the form of vertices defined by the intersection of three, four, or more illusory contours that meet at a point. A direct extension of the collinear completion models to account for these phenomena tends towards a combinatorial explosion, because it would suggest cells with specialized receptive fields configured to perform each of those completion types, each of which would have to be replicated at every location and every orientation across the visual field. These phenomena therefore challenge the adequacy of the neural network approach to account for these diverse perceptual phenomena. I have proposed elsewhere an alternative paradigm of neurocomputation in the harmonic resonance theory (Lehar 1999, see website), whereby pattern recognition and completion are performed by spatial standing waves across the neural substrate. The standing waves perform a computational function analogous to that of the spatial receptive fields of the neural network approach, except that, unlike that paradigm, a single resonance mechanism performs a function equivalent to a whole array of spatial receptive fields of different spatial configurations and of different orientations, and thereby avoids the combinatorial explosion inherent in the older paradigm. The present paper presents the directional harmonic model, a more specific development of the harmonic resonance theory, designed to account for specific perceptual grouping phenomena. Computer simulations of the directional harmonic model show that it can account for collinear contours as observed in the Kanizsa figure, orthogonal contours as seen in the Ehrenstein illusion, and a number of illusory vertex percepts composed of two, three, or more illusory contours that meet in a variety of configurations.

A number of illusory phenomena, for example the Kanizsa illusion, exhibit boundary completion by collinearity between visible inducing edges. These phenomena have been addressed by models such as Grossberg's boundary contour system (BCS) (1985 Psychological Review92 173 – 211), which incorporates collinearity cells with receptive fields specialised to detect and enhance collinearity. Other illusory phenomena like the Ehrenstein illusion exhibit boundary completion orthogonal to the oriented inducers. The BCS model explains such orthogonal grouping by disinhibition, due to competition between collinearity cells of orthogonal orientations. There are many illusory grouping phenomena, however, which exhibit boundary completion through sharp corners in a variety of configurations, producing illusory ‘V’ or ‘Y’ vertices. Examples are seen in the diamond percept of the four-line Ehrenstein illusion, the triangular grouping percept of three dots arranged in a triangular configuration, as well as in the hexagonal percept of a grid of dots in a honeycomb pattern. These completions cannot be explained by models based on collinearity. Lehar's orientational harmonic model (1994, PhD thesis, Boston University) offers a single generalised grouping mechanism capable of collinear, orthogonal, and sharp vertex grouping. The proposed mechanism is a harmonic resonance, or pattern of standing waves in the orientational representation which promotes orientational periodicity. Computer simulations show that the model can account for a large number of diverse illusory phenomena using a single simple mechanism, and predicts the specific conditions under which a grouping of one type yields to a different grouping type.

The generation of illusory contours is closely related to distinct parts of a pattern such as dots, line ends, and corner points. On the other hand, the remarkable property is that gaze at one point of the contours diminishes the illusion and a return of gaze to the whole pattern restores it. Therefore, illusory contours depend on local parts and the whole pattern formed by the parts, and fitting data on the two aspects is necessary to clarify underlying mechanisms. We have obtained such data from the experiments performed to elucidate other visual phenomena. On the basis of the data, the concepts of strength of pattern, strength of its spread effect, ridgelines of the spread effect, and a hollow of the spread effect are introduced and then various phenomena on illusory contours, including the Kanizsa triangle, are explained in terms of these concepts.

In order to include the monocular areas from the left and the right eye in the cyclopean view, the visual system displaces the occluded elements which would result in a horizontal elongation of the shape but does not occur thanks to a correction mechanism which preserves the shape. We hypothesised that this mechanism causes Kanizsa's a modal shrinkage illusion (the apparent elongation of a partially occluded square) when it is incorrectly applied by the visual system to a two-dimensional stimulus. Four experiments tested this hypothesis: (i) one-eyed observers were less susceptible to the illusion than people with normal binocular vision because, for them, the correction for shape is unnecessary; (ii) the illusion was stronger with binocular than with monocular vision since binocularity induces the visual system to correct for the shape distortion; (iii) the illusion diminished when the stimulus was rotated 90° given that displacement and compression are not required for vertical occlusion; (iv) the magnitude of the illusion was a function of the width of the occluder because, as previous research has shown, the edges of a partially occluded square are less displaced the farther they are from the edges of the occluder. The data from the four experiments support our hypothesis even though no condition was able to eliminate the illusion; other possible causes are discussed.

When two figures intersect, two apparently paradoxical size effects take place (Kanizsa, 1979 Organization in Vision chapter 11): (1) the partly occluded figure looks shorter than an identical unoccluded figure, and (2) the modally visible parts of the occluded figure look larger than identical isolated parts. Kanizsa explains such effects as due to amodal completion. Three experiments were carried out by the method of adjustment to test this explanation: two were devoted to the shrinkage effect, and the third one was devoted to the expansion effect. The first experiment exploited the properties of the so-called Helmholtz - Ratoosh law (T-shaped vs Y-shaped junctions) to test whether a figural shrinkage is also present in a pattern in which amodal completion should not occur. The second experiment was aimed at checking whether stereoscopic displacement of the ‘occluded’ figure ‘behind’ or ‘in front of’ the ‘occluding’ one is capable of affecting the amount of shrinkage. In the third experiment the Helmholtz - Ratoosh law was again applied to the expansion. The results of all three experiments converge in showing that the amount of shrinkage of the whole ‘occluded’ figure as well as the ammount of expansion of the ‘modally visible’ parts are not affected by the presence or the absence of amodal completion. We conclude that both the shrinkage and the expansion effects are due to other factors, probably the same factors as those that affect classical optical-geometrical illusions, such as the Oppel - Kundt or the horizontal - vertical illusions.

Illusory displacements in depth may be perceived in simple geometric configurations devoid of cues for spatial computation but also in real-world images where there is no shortage of information of this kind. Two of these different contexts drew the attention of vision scientists as sources of depth illusions: the Kanizsa square and the images of statues that Catalano's created with a part missing. Similar depth alterations occur in both cases: the portions of the background surrounded by “inducers” (pacmen or body parts) are perceived as coming to the foreground. These illusory effects appear more vivid and diverse in the real-world context leading to hypothesize an involvement of the figural complexity in the misperception. A check was carried out by testing the effects of the background articulation on the depth perception of the illusory Kanizsa square. It was confirmed that both background and inducers articulation enhance the phenomenon. A large set of Catalano's images was analyzed, looking for basic distorting sources along the torn contours. Several basic factors were found, but not enough to account for the complexity of this variegated, often paradoxical phenomenon.

Our visual percepts are not fully determined by the physical stimulus input. That is why we perceive crisp bounding contours even in the absence of luminance-defined borders in visual illusions such as the Kanizsa figure. It is important to understand which neural processes are involved in creating these artificial visual experiences because this might tell us how we perceive coherent objects in natural scenes, which are characterized by mutual overlap. We have already shown using functional magnetic resonance imaging [Maertens, M., & Pollmann, S. fMRI reveals a common neural substrate of illusory and real contours in v1 after perceptual learning. Journal of Cognitive Neuroscience, 17, 1553–1564, 2005] that neurons in the primary visual cortex (V1) respond to these stimuli. Here we provide support for the hypothesis that V1 is obligatory for the discrimination of the curvature of illusory contours. We presented illusory contours across the portion of the visual field corresponding to the physiological “blind spot.” Four observers were extensively trained and asked to discriminate fine curvature differences in these illusory contours. A distinct performance drop (increased errors and response latencies) was observed when illusory contours traversed the blind spot compared to when they were presented in the “normal” contralateral visual field at the same eccentricity. We attribute this specific performance deficit to the failure to build up a representation of the illusory contour in the absence of a cortical representation of the “blind spot” within V1. The current results substantiate the assumption that neural activity in area V1 is closely related to our phenomenal experience of illusory contours in particular, and to the construction of our subjective percepts in general.

AbstractWhile seminal theories suggest that nonsymbolic visual numerosity is mainly extracted from segmented items, more recent views advocate that numerosity cannot be processed independently of nonnumeric continuous features confounded with the numerical set (i.e., such as the density, the convex hull, etc.). To disentangle these accounts, here we employed two different visual illusions presented in isolation or in a merged condition (e.g., combining the effects of the two illusions). In particular, in a number comparison task, we concurrently manipulated both the perceived object segmentation by connecting items with Kanizsa-like illusory lines, and the perceived convex-hull/density of the set by embedding the stimuli in a Ponzo illusion context, keeping constant other low-level features. In Experiment 1, the two illusions were manipulated in a compatible direction (i.e., both triggering numerical underestimation), whereas in Experiment 2 they were manipulated in an incompatible direction (i.e., with the Ponzo illusion triggering numerical overestimation and the Kanizsa illusion numerical underestimation). Results from psychometric functions showed that, in the merged condition, the biases of each illusion summated (i.e., largest underestimation as compared with the conditions in which illusions were presented in isolation) in Experiment 1, while they averaged and competed against each other in Experiment 2. These findings suggest that discrete nonsymbolic numerosity can be extracted independently from continuous magnitudes. They also point to the need of more comprehensive theoretical views accounting for the operations by which both discrete elements and continuous variables are computed and integrated by the visual system.

AbstractDetection of illusory contours (ICs) such as Kanizsa figures is known to depend primarily upon the lateral occipital complex. Yet there is no universal agreement on the role of the primary visual cortex in this process; some existing evidence hints that an early stage of the visual response in V1 may involve relative suppression to Kanizsa figures compared with controls. Iso-oriented luminance borders, which are responsible for Kanizsa illusion, may evoke surround suppression in V1 and adjacent areas leading to the reduction in the initial response to Kanizsa figures. We attempted to test the existence, as well as to find localization and timing of the early suppression effect produced by Kanizsa figures in adult nonclinical human participants. We used two sizes of visual stimuli (4.5 and 9.0°) in order to probe the effect at two different levels of eccentricity; the stimuli were presented centrally in passive viewing conditions. We recorded magnetoencephalogram, which is more sensitive than electroencephalogram to activity originating from V1 and V2 areas. We restricted our analysis to the medial occipital area and the occipital pole, and to a 40–120 ms time window after the stimulus onset. By applying threshold-free cluster enhancement technique in combination with permutation statistics, we were able to detect the inverted IC effect—a relative suppression of the response to the Kanizsa figures compared with the control stimuli. The current finding is highly compatible with the explanation involving surround suppression evoked by iso-oriented collinear borders. The effect may be related to the principle of sparse coding, according to which V1 suppresses representations of inner parts of collinear assemblies as being informationally redundant. Such a mechanism is likely to be an important preliminary step preceding object contour detection.

A remarkable feature of artist Fred Sandback’s string constructions has often been noted: that the geometrical forms created with string have a strong planar feel. Phenomenologically, the spaces between the strings are perceived as planes with some substance. The illusion is amodally completed, as in the famous Kanizsa triangle, by minimal prompts, but in three dimensions. Instead of an illusory figure, then, Sandback creates illusory planes. By noting how the constructions are like “impossible” figures, we can see how bottom up and top down effects combine to complicate the illusion and the works become about the construction of space rather than its reification.

AbstractThe ability to complete partially missing contours is widespread across the animal kingdom, but whether this extends to dogs is still unknown. To address this gap in knowledge, we assessed dogs’ susceptibility to one of the most common contour illusions, the Kanizsa’s triangle. Six dogs were trained to discriminate a triangle from other geometrical figures using a two-alternative conditioned discrimination task. Once the learning criterion was reached, dogs were presented with the Kanizsa’s triangle and a control stimulus, where inducers were rotated around their centre, so as to disrupt what would be perceived as a triangle by a human observer. As a group, dogs chose the illusory triangle significantly more often than control stimuli. At the individual level, susceptibility to the illusion was shown by five out of six dogs. This is the first study where dogs as a group show susceptibility to a visual illusion in the same manner as humans. Moreover, the analyses revealed a negative effect of age on susceptibility, an effect that was also found in humans. Altogether, this suggests that the underling perceptual mechanisms are similar between dogs and humans, and in sharp contrast with other categories of visual illusions to which the susceptibility of dogs has been previously assessed.

Introduction – Polish GrungeThe main objective of this article is to examine the grunge scene of the 1990s in Poland in the context of acculturation and assimilation processes. Polish grunge was, on the one hand, the expression of trends that were observable in music industry since the late 1980s. On the other hand, it was symptomatic of a rapid systemic transformation. Youth culture was open for the diffusion of cultural patterns and was ready to adopt certain patterns from the West.Thus, we suggest that the local grunge scene was completely modelled on the American one: the flow of cultural practices and subcultural fashion were the manifestations of the assimilation processes in Poland, observable not only in art (i.e. rock music), but also in the domains of politics and economy, as well as in the broader social sphere. We explore how young people were ready to adopt only the surface level of the phenomenon as they were familiar with it through the media coverage it received. Young people in Poland circa the early ‘90s primarily wanted to gain access to an imaginary Western lifestyle rather than learn about real living conditions in capitalist societies, and they could do this through their involvement in grunge culture.Grunge as a Cultural PhenomenonGrunge as a popular music trend arose in the USA during the late 1980s and early 1990s, in the work of bands such as Nirvana, Pearl Jam, Stone Temple Pilots, Soundgarden, and Alice in Chains. Grunge was initially opposed to consumerism and capitalist values. Nevertheless, A&R scouts recognised the commercial potential of this music: for example, Nirvana’s Nevermind was released by Geffen Company, and Pearl Jam’s Ten by Epic. As Grzegorz Brzozowicz and Filip Łobodziński put it (313),the success of Nirvana was a post-mort triumph of punk rock and, more importantly, it indicated the potential of alternative music, which suddenly stepped outside an aesthetic ghetto and became a hot stuff. This influence was also visible as regards fashion and customs – Dr. Martens’ shoes, flannel shirts, frayed jeans, and wool caps became an outfit common for the young (…). Grunge influenced visual art, film and photography.In Poland, grunge as a subculture and sub-genre of rock music emerged in the early 1990s following the international commercial success of bands such as those listed above, and it entailed the assimilation of the Western cultural patterns. Although assimilation processes were typical primarily for youth culture, they were observed in the wider context of the changes and adaptations that Polish system underwent after the fall of the centrally planned economy and subjugation to the communist party power after the Yalta agreements (1945-1989/1990).In this context, the concept Centre/Periphery (Gopinathan, Saravanan and Altbach; Hannerz; Langholm; Pisciotta) appears as the field for the dissemination of popular culture. Popular culture is a battlefield for creating and negotiating the meanings that are inherent within cultural practices (Barker). Cultural practices play a double role in the dissemination of ideas or objects. Firstly, they come as a result of adaptation in a defined culture, and secondly, they make new cultural patterns stabile, visible, and easy to practice by people as flexible patterns of behaviour. This point is clearly visible in the context of the East European states that underwent rapid acculturation processes in which new patterns of economic and social solutions were established in centre-planned economies: the tensions of the “old” and the “new” patterns dominating in the political and social systems of those countries (e.g. Poland, the Czech Republic, Latvia, Lithuania, etc.) were visible and affected societies to a considerable degree (Pisciotta). Thus, the practices generated in cultural Centres tend to disseminate easily and to “conquer” other cultural systems, especially in the Periphery.In the case of popular culture, the flow of influences usually takes a one-dimensional form and is disseminated from the Centre to the Periphery. As Marek Jeziński (162-163) argues, both Centre and Periphery are functional systems. These systems have generated their own mythology, which separates one from another. However, as in the case of mythological systems in general, Centre and Periphery tales overlap frequently, and there are evidence that the bands that originated in the Periphery were assimilated by the Centre. For example, Nirvana and Pearl Jam were both successful in market terms and both built their own status based on the Peripheral components that were skilfully overtaken by the Centre narrative. While the Peripheral narratives are concentrated mainly on the undermining of the definition of situation and present dysfunctional character towards cultural system as such, the Centre narratives aim to maintain the definition of situation supporting mainstream values and their prevailing position in a system (Jeziński 164). Grunge is the epitome of such an implementation of cultural patterns. That is, grunge started as a fringe peripheral cultural phenomenon. The major records companies, however, recognised its potential and provided the space in the music market to support the new bands. Most of the groups in the US started as independent local acts related to independent record companies that built their status.In relation to the assimilation of grunge culture in Poland, we can distinguish two key phenomena. The first is concerned with the adaptation of general subcultural components, e.g. fashion and group identification. Here, the acculturation processes run as a primary form of mimicry, as the Polish grunge scene adopted elements typical of the grunge subculture, such as oversize sweaters, flannel shirts, Dr. Martens shoes or Converse trainers, long hair, and beanies. A newly formed subculture was different from the others popular in the 1990s. For example, punk and metal subcultures implied strong group identity, style homogeneity, rigid group limitations, and firm membership rules. Conversely, it seems that the grunge subculture was based more on a level of liquid and fragmented patchwork identity than on very inflexible group values and internal ideology or political attitudes (cf. Muggleton). Such patchwork identity formation was a result of a rapid clash between the adaptation of grunge cultural patterns from the West and the Polish economic transformation of the early 1990s.Poland underwent rapid changes that were also visible in the politics, culture and social domain, joining liberal democracies and liberal free market economies of the West. These changes resulted from a transformation of the system as a whole: from a central planned system to decentralisation of the power at both local and state levels (Sarnecki). Equally important were the changes in the political culture of Poles and their value system: they accepted the democratic changes but simultaneously, the mentality of Poles remained traditionalist (which is visible in surveys— the most important values for them were “family” and “work”), and their attitude towards the processes of cultural and institutional changes was impermanent (Garlicki; Jasińska-Kania).During the transformation, the changes were visible in the everyday lives of Polish citizens: examples include the shortages in the market that were evident after the socialist regime ended, and the easy availability of Western clothes such as jeans, shirts, denim jackets in ordinary stores. Consequently, the economic rates in the 1990s were higher in comparison to the previous decade (Bałtowski and Miszewski). Those changes resulted in a phase shift in the modernisation process, where patterns of economic and cultural development and were faster than the enculturation and socialisation processes.On the one hand, the free market allowed for almost unlimited commodification with unprecedented access to goods and services. On the other hand, the low cultural capital and economic possibilities of the citizens evolved rapidly. The communist-shaped social division fell apart, and the new class designations based of consumption/commodification patterns were established (Jeziński; Wojtkowski). Those factors resulted in high cross-generational mobility, lower entrance barriers, and higher openness indicators (cf. Polska klasa średnia; O ruchliwości społecznej w polsce).Hence, in cultural conditions based on capitalist consumption practices, the grunge subculture evolved with a commodified sense of style rather than with a firm identity. Yet, in the case of grunge style, relatively high costs of subculture commodities (e.g. Dr. Martens shoes, Converse trainers, or band t-shirts) led to DIY practices such as buying cheaper no-name shoes, and sewing badges with the names of bands and albums on jackets or backpacks.The second phenomenon encompasses the adaptation of music patterns. The Polish grunge scene was not as diversified in terms of genre variations as its US counterpart. In the beginning, the Polish grunge scene was more distressed geographically, with no specific Centre-Periphery relations. However, one of the most important bands, Hey, was established in the Northwest. When one looks at Polish grunge evolution as a ‘clash’ of American genre and the specific character of a time and place where Polish bands were recording, she or he will notice multiple similarities with the US scene.Firstly, we could name two approaches to grunge music among Polish performers: ‘intellectual’ and ‘rebel’. The ‘intellectual’ approach encompasses the group Hey. This band was established in Szczecin (the Northwest Poland), but after the success of their first album – Fire (1993), they moved to Warsaw. Hey released 11 studio records, but only the first three could be classified as “grunge” (cf. Sankowski). On the level of musical references, Fire sounds like a mixture of early Pearl Jam combined with Alice in Chains. With English lyrics and song topics that were typical for grunge— e.g., The Choice (“You’ve got a gun/You can use it now”)—similarities with Pearl Jam, in particular, are striking. The band evolved, and on their second album, Ho! (1994), Hey mixed equally Polish and English lyrics with the dynamic and specific Seattle sound (cf. Prato). Hey’s most distinctive feature comparing with other Polish grunge bands is its highly developed melodic approach to music and the poetic, sensual style of its lyrics. The third record, ? (1995), closes the band’s early stage. The next album, Karma (1997), opens the period when the amalgamation of electronics, hard rock and grunge dominated Hey’s music, with the album [sic!] (2001) representing the turning point in the group’s music style. The band suspended their work in 2017 and will probably never reunite.Over time, Hey gained one of the most dedicated audiences in Polish rock music. The music industry and critics have acknowledged Hey as one of the best Polish groups in the post-communist period. Hey has received the most nominations in the history of Fryderyki, the key Polish music awards. The group and Nosowska have won twenty-three times in multiple categories. As the longest-operating grunge-origin band in the country, Hey could be considered as a most important trend setting and scene-forming group.The more “rebellious” approach to grunge encompasses bands such as Illusion (1992-1999, 2014-present) and Houk. The former was based on the grunge and hardcore mixture of influences from Alice in Chains, Soundgarden, and Rage Against the Machine (especially in terms of rap-oriented lyrics). With the preservation of certain consistency, the band named first three albums: Illusion (1993), Illusion II (1994), and Illusion III (1995). Illusion marks the band’s aggressive style and lyrics simplicity but the studio production flattens the whole and gives an impression of a post-punk DIY venture rather than a coherent composition. The second record, however, is entirely conceptualised and thought out in terms of music and lyrics. Sharp riffs, hard rock tuning of instruments and aggressive lyrics that were focused on Polish life gave the album a needed consistency. The band’s third record is the most varied stylistically and politically engaged in their history. The harder-edged tunes from previous releases are accompanied by more psychedelic compositions (Wrona) that recall Alice in Chains’ slow songs and Layne Staley’s voice.Houk’s music similarly to other Polish grunge bands was the amalgamation of various genres and their style evolved in time. Initially, the band was regarded as an example of alternative rock music. The first album Soul Ammunition (1992) was named by music monthly Tylko Rock as a debut of the year (polskirock.art.pl). The combination of grunge, hardcore, hard rock, reggae and socio-politically engaged lyrics helped the group to establish a strong fan base. The band’s unique style was recognised internationally and Houk supported New Model Army and Bad Brains during the performances in the mid-1990’s (polskirock.art.pl). The band’s second studio release Generation X (1995) was recorded prior the multiple membership reorganizations that finally ended the grunge-orientation period of Houk’s history. One of the songs, Sleep, was dedicated to Kurt Cobain and reflected Nirvana’s approach to songwriting, which can be heard in songs such as “Lithium” (1991). Such a commemoration of Cobain’s figure is characteristic of Polish grunge culture’s establishment of strong ties with the American equivalent. Here and in many similar cases, Cobain serves not only as a grunge hero (or even a martyr) but also as a commodified pop culture figure (cf. Strong). Concerning both spheres - that is, the adaptation of grunge subculture and a development of the music scene -Polish grunge follows a different pattern to the US genre. Grunge was introduced to Poland after it was popularised and commodified by the major labels and media industry in the USA, so the adopted version was the mainstream one rather than the underground movement. Hence, the simplistic dichotomy between “underground” and “mainstream” culture does not function in terms of the Polish grunge culture, and probably is misstated even when it comes to the American phenomenon. Grunge could be perceived in Poland as both the first and the last “true” subcultural trend. At the same time, though, it was an affirmation not of ‘the rebel’ and ‘the underground’ but of capitalism and the cultural values of the West. Indeed, the Polish grunge culture couldn’t be fully aware of what grunge was warning us against while Polish society faced the rapid market and cultural transformation that allowed for its opening to Western trends.Conclusion – Is Grunge Really Dead?Although the popularity of grunge phenomenon in Poland was relatively short, the most important groups of this sub-genre - Illusion, Hey, Ahimsa, Houk, and Kr’shna Brothers - widely contributed to the emergence of the new wave of fashion for rock and hard-rock music in Poland in the mid-1990s. The most successful group of the era, Hey epitomises the transformation of grunge in Poland. Starting as a typical grunge band (modelled heavily on the US groups), they underwent a serious transition, substantially changing their music into more mainstream-oriented rock (that is, as music that was considered acceptable by rock music and AOR-focused radio stations). At the same time, grunge as a rock sub-genre underwent the contrary changes: it broke into the mainstream relatively quickly in the first half of the 1990s, establishing new rock stars of the scene (Illusion, Houk, Ahimsa, Hey), but in the late 1990s it went back to being a rock niche again. It seems that today grunge serves as a point of reference (in fact, it was an important period of rock history) for the new bands that intentionally use this sub-genre as a form of commodified, media-friendly nostalgia.ReferencesBałtowski, Maciej, Miszewski, Maciej. Transformacja gospodarcza w Polsce. 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