Several authors have characterized a striking phenomenon of perceptual learning in visual discrimination tasks. This learning process is selective for the stimulus characteristics and location in the visual field. Since the human visual system exploits symmetry for object recognition we were interested in exploring how it learns to use preattentive symmetry cues for discriminating simple, meaningless, forms. In this study, similar to previous studies of perceptual learning, we asked whether the effects of practice acquired in the (...) discrimination of pairs of shape with a specific orientation of the symmetry axis would transfer to the discrimination of shapes with different orientation of symmetry axis, or to shapes presented in different areas of the visual field. We found that there was no learning transfer between forms with very different axes of symmetry (90° apart). Interestingly, however, we found a transfer of learning effect to horizontally oriented symmetry axis from a condition with an axis of symmetry differing by 45°. Also it appears that some subjects took a longer time to learn than the typical fast learning paradigm would predict. Data showed that when observers practice discrimination of meaningless symmetric forms, consistent improvement in the performance occurs. This improvement is lasting over days, and it tends to be specific for the area of the visual field trained. We will discuss results from some of the observers whose learning was not fast, but who actually improved with more practice and with large time intervals (1 day) between training sessions. (shrink)

Some philosophers claim that to see something you must discriminate it from other things. But they do not tell us what it is to discriminate something. I distinguish five types of discrimination. Then I argue that the plausibility of the claim that seeing something requires discriminating it, as opposed to simply attributing some properties to it, hinges on the type of discrimination under consideration. A weak form of discrimination trivializes the debate. Stronger notions of discrimination, (...) however, cannot be understood without attribution (i.e., representation-as). Attribution appears to form the fundamental level of personal-level representation. (shrink)

Priming and recollection are expressions of human memory mediated by different brain events. These brain events were monitored while people discriminated words from nonwords. Mean response latencies were shorter for words that appeared in an earlier study phase than for new words. This priming effect was reduced when the letters of words in study-phase presentations were presented individually in succession as opposed to together as complete words. Based on this outcome, visual word-form priming was linked to a brain (...) potential recorded from the scalp over the occipital lobe about 450 ms after word onset. This potential differed from another potential previously associated with recollection, suggesting that distinct operations associated with these two types of memory can be monitored at the precise time that they occur in the human brain. (shrink)

The dissertation examines the intersection of language and sense discrimination in the texts of classical Chinese philosophy . Through an analysis of the figures of speech related to language and sense discrimination, it argues that the pair 'aural and visual' forms a significant dualism within the Chinese cosmos. ;The significance of the aural/visual dualism is threefold. First, it clarifies classical Chinese epistemology. The dissertation argues that classical Chinese epistemology is a matter of matching many levels of (...) parallels between the aural and the visual. In other words, knowledge in classical China is verified through correspondences between the aural and visual. ;Second, the aural/visual dualism challenges a common assumption that in classical China sense discrimination is natural while language is conventional. The aural and visual are two aspects of sense discrimination, but they are also two aspects of language. That is, the category 'language' extends over both sides of the dualism. It is both aural and visual . As a result, the contrast of 'language as conventional' in opposition to 'sense discrimination as natural' does not develop in classical China. Both language and sense discrimination are to some extent both natural and conventional. ;Thirdly, the importance of the aural and visual is connected to the pair ming/shi. Ming/shi is typically translated 'names and reality' or 'names and objects' on the assumption that shi is more substantial and therefore more real. But as a form of the aural/visual dualism, there seems to be no justification for taking shi as 'reality'. Shi is what is seen by the eyes, just as ming is what is heard by the ears, but neither appears more intrinsically 'real'. Thus, the dissertation argues that in light of the aural/visual dualism we must reconsider what constitutes the notion of reality in classical China. (shrink)

It has not been clarified if attention influences perception of targets in visual masking. Three forms of common masks were thus chosen in the present study and presented with character targets in three temporal sequences. In order to pinpoint the level of processing where masking arises, character targets were varied in depth of processing from random arrangements of strokes up to real Chinese characters. The attentional influence was examined under perceptual discrimination and lexical decision tasks, respectively. The results (...) revealed significant interactions among four factors. Identification of character targets in each form of mask sequence varied with task demand, with greater suppression in the perceptual discrimination task. These findings suggested that attentional demand can bias processing in favor of task-related information in visual masking. Variations in masking effects may be contributed by both attentional demand and spatio-temporal interaction. (shrink)

PurposeThis study investigated the impact of age and myopia on visual form perception among Chinese school-age children.MethodsThis cross-sectional study included 1,074 students with a mean age of 12.1 ± 4.7 years. The mean spherical equivalence refraction of the participants was −1.45 ± 2.07 D. All participants underwent distance visual acuity, refraction measurement and local and global visual form perception test including orientation, parallelism, collinearity, holes and color discrimination tasks.ResultsThe reaction times of emmetropes were slower (...) than those of myopic and high myopic groups on both local and global discrimination tasks. A reduction in reaction times was found with increasing age on both local and global discrimination tasks. Age was significantly associated with both local and global visual perception performance after adjusting for gender, visual acuity and SER.ConclusionsThis study revealed that both local and global visual perception improve with age among Chinese children and that myopes seem to have better visual perception than emmetropes. (shrink)

Music can act as a mnemonic device that can elicit multiple memories. How musical and non-musical information integrate into complex cross-modal memory representations has however rarely been investigated. Here, we studied the ability of human subjects to associate visual objects with melodies. Musical laypersons and professional musicians performed an associative inference task that tested the ability to form and memorize paired associations between objects and melodies and to integrate these pairs into more complex representations where melodies are linked (...) with two objects across trials. We further investigated whether and how musical expertise modulates these two processes. We analyzed accuracy and reaction times of direct and indirect trials in both groups. We reasoned that the musical and cross-modal memory demands of musicianship might modulate performance in the task and might thus reveal mechanisms that underlie the association and integration of visual information with musical information. Although musicians showed a higher overall memory accuracy, non-musicians’ accuracy was well above chance level in both trial types, thus indicating a significant ability to associate and integrate musical with visual information even in musically untrained subjects. However, non-musicians showed shorter RTs in indirect compared to direct trials, whereas the reverse pattern was found in musicians. Moreover, accuracy of direct and indirect trials correlated significantly in musicians but not in non-musicians. Consistent with previous accounts of visual associative memory, we interpret these findings as suggestive of at least two complimentary mechanisms that contribute to visual-melodic memory integration. A default mechanism that mainly operates at encoding of complex visual-melodic associations and that works with surprising efficacy even in musically untrained subjects. A retrieval-based mechanism that critically depends on an expert ability to maintain and discriminate visual-melodic associations across extended memory delays. Future studies may investigate how these mechanisms contribute to the everyday experience of music-evoked memories. (shrink)

Multiple versions of the Chinese Remote Associates Test have been developed. Thus far, all CRATs have employed verbal stimuli; other forms of stimuli have not yet been used. In this context, the present study compiled a Chinese Visual Remote Associates Test that conforms to the Chinese language and culture based on a picture naming database. The developed CVRAT has two versions, CVRAT-A and CVRAT-B, each comprising 20 test questions. A typical CVRAT question consists of three stimuli pictures, requiring respondents (...) to propose a target word that is semantically associated with all the pictures. When compiling the CVRAT, this study first selected target words, sifted through stimuli words and corresponding pictures, and analyzed pilot test questions. After compilation, their reliability and validity were examined. The results showed that the CVRAT had moderate internal consistency reliability, good criterion-related validity for the Chinese Word Remote Associates Test, Chinese Radical Remote Associates Test, Chinese Compound Remote Associates Test, insight problem-solving, as well as acceptable discriminant validity for fluency, flexibility, and originality of a divergent thinking test. In other words, CVRAT can effectively measure remote associative capability and provides a figural creativity test that facilitates the understanding of different kinds of remote associations. (shrink)

Silent gesture is not considered to be linguistic, on par with spoken and sign languages. It is claimed that silent gestures, unlike language, represent events holistically, without compositional structure. However, recent research has demonstrated that gesturers use consistent strategies when representing objects and events, and that there are behavioral and clinically relevant limits on what form a gesture may take to effect a particular meaning. This systematicity challenges a holistic interpretation of silent gesture, which predicts that there should be (...) no stable form‐meaning correspondence across event representations. Here, we demonstrate to the contrary that untrained gesturers systematically manipulate the form of their gestures when representing events with and without a theme (e.g., Someone popped the balloon vs. Someone walked), that is, transitive and intransitive events. We elicited silent gestures and annotated them for manual features active in coding transitivity distinctions in sign languages. We trained linear support vector machines to make item‐by‐item transitivity predictions based on these features. Prediction accuracy was good across the entire dataset, thus demonstrating that systematicity in silent gesture can be explained with recourse to subunits. We argue that handshape features are constructs co‐opted from cognitive systems subserving manual action production and comprehension for communicative purposes, which may integrate into the linguistic system of emerging sign languages. We further suggest that nonsigners tend to map event participants to each hand, a strategy found across genetically and geographically distinct sign languages, suggesting the strategy's cognitive foundation. (shrink)

Training can influence behavioral performance and lead to brain reorganization. In particular, training in one modality, for example, auditory, can improve performance in another modality, for example, visual. Previous research suggests that one of the mechanisms behind this phenomenon could be the cross-modal recruitment of the sensory areas, for example, the auditory cortex. Studying expert musicians offers a chance to explore this process. Rhythm is an aspect of music that can be presented in various modalities. We designed an fMRI (...) experiment in which professional pianists and non-musicians discriminated between two sequences of rhythms presented auditorily or visually. Behavioral results showed that musicians performed in both visual and auditory rhythmic tasks better than non-musicians. We found no significant between-group differences in fMRI activations within the auditory cortex. However, we observed that musicians had increased activation in the right Inferior Parietal Lobe when compared to non-musicians. We conclude that the musicians’ superior visual rhythm discrimination is not related to cross-modal recruitment of the auditory cortex; instead, it could be related to activation in higher-level, multimodal areas in the cortex. (shrink)

This somewhat odd paper argues against a representational view of visual experience using an intricate "inversion" type thought experiment involving double vision: two subjects could represent external space in the same way while differing phenomenally due to different "spread" in their double images. The spatial structure of the visual field is explained not by representation of external space but functionally, in terms of the possible locations of an attentional spotlight. -/- I'm fond of the ideas in this paper (...) but doubt I'll be returning to it soon. (shrink)

In The Society of the Spectacle, Debord describes the spectacle as a capitalist social formation that is at the same time reflective of the privileging of vision in the history of Western philosophy. This article highlights Debord’s appeal to the Hegelian-Marxist notion of reciprocal alienation in his discussion of how the spectacle invents the visual form. Reciprocal alienation produces a dialectical relation between concrete social activity and the spectacle, which I argue is key for understanding how the political (...) subject is represented in the hyper-spectacularized societies of the 21st century. (shrink)

The cortical visual mechanisms involved in processing spatial relationships remain subject to debate. According to one current view, the ''dorsal stream'' of visual areas, emanating from primary visual cortex and culminating in the posterior parietal cortex, mediates this aspect of visual processing. More recently, others have argued that while the dorsal stream provides egocentric coding of visual location for motor control, the separate ''ventral'' stream is needed for allocentric spatial coding. We have assessed the (...) class='Hi'>visual form agnosic patient DF, whose lesion mainly affects the ventral stream, on a prehension task requiring allocentric spatial coding. She was presented with transparent circular disks. Each disk had circular holes cut in it. DF was asked to reach out and grasp the disk by placing her fingers through the holes. The disks either had three holes (for forefinger, middle finger, and thumb) or two holes (for forefinger and thumb). The distance between the forefinger and thumb holes, and the orientation of the line formed by them, were independently varied. DF was quite unable to adjust her grip aperture or her hand orientation in the three-hole task. Although she was able to orient her hand appropriately for the two-hole disks, she still remained unable to adjust her grip aperture to the distance between the holes. These findings are consistent with the idea that allocentric processing of spatial information requires a functioning ventral stream, even when the information is being used to guide a motor response. (shrink)