The effect of memory color on form identification

Previous studies have demonstrated that a form’s identity affects the phenomenal hue of that form. This effect has been attributed to the operation of the “memory color” phenomenon. The present study was proposed to assess the effect of “memory” or characteristic color on form identification. Results indicate that memory color, rather than interacting with the object in such a manner as to aid identification, induces a bias toward identification of an object of the memory color.     

Perceptual selectivity for color and form

Three visual-search experiments tested whether the preattentive parallel stage can-selectively guide the attentive stage to a particular known-to-be-relevant target feature. Subjects searched multielement displays for a salient green circle that had a unique form when surrounded by green nontarget squares or had a unique color when surrounded by red nontarget circles. In the distractor conditions, a salient item in the other dimension was present as well. As an extension of earlier findings (Theeuwes, 1991), the results showed that complete top-down selectivity toward a particular feature was not possible, not even after extended and consistent practice. The results reveal that selectivity depends on the relative discriminability of the stimulus dimensions: the presence of an irrelevant item with a unique color interferes with parallel search for a unique form, and vice versa.     

Attentional capacity is undifferentiated: concurrent discrimination of form, color, and motion

We report a series of experiments on the concurrent discrimination of form, color, and motion attributes. All tasks involved joint discrimination of attributes, and positions and were highly demanding of attention. We quantified interference between concurrent discriminations by establishing the attention-operating characteristic. Interference was indistinguishable for similar and dissimilar task combinations (form-form, color-color, motion-motion, and color-form, color-motion, motion-color, and motion-form, respectively). These results suggest strongly that different visual discriminations draw on the same attentional capacity--in other words, that the capacity of visual attention is undifferentiated.     

Adolescents' visual preference for color over form

This study is concerned with the visual preference for color over form among the Yoruba adolescents of Nigeria. The hypothesis is that Yoruba adolescent boys are more likely to demonstrate superior performance in a task involving cultural differences in visual selective attention preference for color over form than girls. One hundred 16-year-old adolescent boys and girls were randomly drawn from two secondary schools for this study. The instrument used was the Visual Selective Attention Color-Form Matching Experiment. Computation was carried out with a chi-square 2 X 2 contingency analysis. Results indicated that the hypothesis reached a .001 statistical level of significance. The theoretical implications of the findings are discussed.     

Perceptual selectivity for color and form.

Three visual-search experiments tested whether the preattentive parallel stage can selectively guide the attentive stage to a particular known-to-be-relevant target feature. Subjects searched multielement displays for a salient green circle that had a unique form when surrounded by green nontarget squares or had a unique color when surrounded by red nontarget circles. In the distractor conditions, a salient item in the other dimension was present as well. As an extension of earlier findings (Theeuwes, 1991), the results showed that complete top-down selectivity toward a particular feature was not possible, not even after extended and consistent practice. The results reveal that selectivity depends on the relative discriminability of the stimulus dimensions: the presence of an irrelevant item with a unique color interferes with parallel search for a unique form, and vice versa.     

The capacity for rapid shifts in level of mental concentration

This investigation continues the exploration of a largely neglected topic in the field of attention, levels of mental concentration, by ascertaining under optimal conditions the capacity for shifting quickly from one level to another. Previous research in our laboratory had applied a set of five post-hypnotically cued levels of concentration or “cognitive arousal”, covering a very wide range, to a variety of perceptual and cognitive tasks. In the present study two highly trained undergraduate hypnotic subjects, one male and one female, were given progressively shorter time durations in which to respond to the post-hypnotic cues before viewing tachisto-scopically flashed consonants under cue influence. The results indicate a striking capacity to shift degrees of cognitive arousal very rapidly to one extreme or the other, on the order of 100 ms or less.     

The representation of color and form in long-term memory

Color and form are elementary stimulus encoding dimensions that have effects on the representation of visual stimuli at early processing stages. Little is known, however, about their effects on visual long-term memory. In three experiments we investigated whether color is part of the memory representation, whether color and form are bound in the memory representation, and the effect of color context on memory performance. Experimental results suggest that color is part of the memory representation and that color and form can be represented separately in memory and accessed independently. We suggest that the binding of color and form is a deliberate strategic act that requires focal attention, not a natural consequence of processing visual stimuli. We compare our results with the predictions of two computational memory models regarding feature binding. The effect of color context was not straightforward; however, results are consistent with the encoding specificity principle.     

The politics of color: Preferences for Republican red versus Democratic blue

The present study reveals that Election Day differentially affects the color preferences of US Republicans and Democrats. Voters’ preferences for Republican red and Democratic blue were assessed, along with several distractor colors, on and around the 2010 interim and 2012 presidential elections. On non-Election Days, Republicans and Democrats preferred Republican red equally, and Republicans actually preferred Democratic blue more than Democrats did. On Election Day, however, Republicans’ and Democrats’ color preferences changed to become more closely aligned with their own party’s colors. Republicans liked Republican red more than Democrats did, and no longer preferred Democratic blue more than Democrats did. These results are consistent with the hypothesis that color preferences are determined by people’s preferences for correspondingly colored objects/entities (Palmer & Schloss in Proceedings of the National Academy of Sciences 107:8877–8882, 2010). They further suggest that color preferences are calculated at a given moment, depending on which color–object associations are currently most activated or salient. Color preferences are thus far more dynamic and context-dependent than has previously been believed.     

The retrieval of scaled English consonants

Two scales of the perceptual differences among English consonants had been constructed earlier, one from pairs of aural syllables and one from pairs of viewed one-syllable English words. In both instances the pairs of stimuli differed only in the initial consonants. In the present work 276 pairs of syllables were assembled in sets of six. A set was viewed sequentially for 1.5 sec/slide. Then 25 subjects who worked in groups of 4–6 attempted to write one randomly chosen omitted member of each pair on an answer form; another 25 subjects were asked to supply the opposite syllables of each pair. This task was termed primary memory. Fifty additional subjects repeated the tasks but spent 10 sec counting backward by 3s before trying to recall and write the missing syllables, thus setting up a task of secondary memory. Response forms were scored for right, wrong, and omitted responses. All responses were then compared with each of the scales referred to above, and the mean value for each group of 50 subjects (25 who used the anser form in theab order+ 25 who used theba order) was computed. The difference between the scores for the two tasks was statistically significant, as was the difference between the scores yielded by the two scales. The visual scale appeared to fit the data better than the aural scale. The procedures employed and the assumptions that were made yielded results that would not justify an opinion that an error in recall is typically almost right. However, the data did reflect partial forgetting.     

Explanation for neon color effect of chromatic configurations on the basis of perceptual ambiguity in form and color

Under reflected light conditions, we observed a neon color effect in a van Tuijl-type pattern for 30 combinations by pairing CMY inks. The results cannot be fully explained by Bressan's proposal as follows: (1) the illusory colors for the six configurations contradicted her predictions, (2) strong effects were not presented for complementary color pairs, and (3) for four configurations, the colors of line segments assimilated into those of the inducing patterns. Thus, the author proposes an hypothesis that the visual system treats neon color displays as ambiguous figures in form and color. This proposal can explain both illusory colors of the illusory area and those of the line segments themselves.     

The effect of color (red versus blue) on assimilation versus contrast in prime-to-behavior effects

This paper examines whether color can modify the way that primed constructs affect behavior. Specifically, we tested the hypothesis that, compared to the color white, blue is more likely to lead to assimilative shifts in behavior, whereas red is more likely to lead to contrastive changes in behavior. In our experiment, previous findings were replicated in the white color condition: participants’ behavior assimilated to primed stereotypes of (un)intelligence and contrasted away from primed exemplars of (un)intelligence. However, in the blue color condition, participants’ behavior assimilated to the primed constructs, whereas in the red color condition, participants’ behavior contrasted away from the primed constructs, irrespective of whether the primed constructs were stereotypes or exemplars.     

The quest for generalizations over consonants: Asymmetries between consonants and vowels are not the by-product of acoustic differences

Consonants and vowels may play different roles during language processing, consonants being preferentially involved in lexical processing, and vowels tending to mark syntactic constituency through prosodic cues. In support of this view, artificial language learning studies have demonstrated that consonants (C) support statistical computations, whereas vowels (V) allow certain structural generalizations. Nevertheless, these asymmetries could be mere by-products of lower level acoustic differences between Cs and Vs, in particular the energy they carry, and thus their relative salience. Here we address this issue and show that vowels remain the preferred targets for generalizations, even when consonants are made highly salient or vowels barely audible. Participants listened to speech streams of nonsense CVCVCV words, in which consonants followed a simple ABA structure. Participants failed to generalize this structure over sonorant consonants (Experiment 1), even when vowel duration was reduced to one third of that of consonants (Experiment 2). When vowels were eliminated from the stream, participants showed only a marginal evidence of generalizations (Experiment 4). In contrast, participants readily generalized the structure over barely audible vowels (Experiment 3). These results show that different roles of consonants and vowels cannot be readily reduced to acoustical and perceptual differences between these phonetic categories.     

The perception of stop consonants by children

Kindergarten and second-grade children's perception of voicing distinctions among the stop consonants was investigated by assessing their ability to identify and discriminate a series of synthetic speech stimuli varying in voice onset time (VOT). Perception of these sounds was found to be nearly categorical. No differences between the two age groups in either identification or discrimination performance were found; furthermore, the children's performance was comparable to adult performance in other studies using these stimuli. When considered in the context of data on the perception of VOT by infants as well as adults, the results suggest that the differential discriminability of stimuli along the VOT continuum has a biological basis.     

Insights from a failure of selective adaptation: syllable-initial and syllable-final consonants are different

Selective adaptation with a syllable-initial consonant fails to affect perception of the same consonant in syllable-final position, and vice versa. One account of this well-replicated result invokes a cancellation explanation: with the place-of-articulation stimuli used, the pattern of formant transitions switches according to syllabic position, allowing putative phonetic-level effects to be opposed by putative acoustic-level effects. Three experiments tested the cancellation hypothesis by preempting the possibility of acoustic countereffects. In Experiment 1, the test syllables and adaptors were /r/-/l/CVs and VCs, which do not produce cancelling formant patterns across syllabic position. In Experiment 2, /b/-/d/ continua were used in a paired-contrast procedure, believed to be sensitive to phonetic, but not acoustic, identity. In Experiment 3, cross-ear adaptation, also believed to tap phonetic rather than acoustic processes, was used. All three experiments refuted the cancellation hypothesis. Instead, it appears that the perceptual process treats syllable-initial consonants and syllable-final ones as inherently different. These results provide support for the use of demisyllabic representations in speech perception.     

Subset selective search on the basis of color and preview

In the preview paradigm observers are presented with one set of elements (the irrelevant set) followed by the addition of a second set among which the target is presented (the relevant set). Search efficiency in such a preview condition has been demonstrated to be higher than that in a full-baseline condition in which both sets are simultaneously presented, suggesting that a preview of the irrelevant set reduces its influence on the search process. However, numbers of irrelevant and relevant elements are typically not independently manipulated. Moreover, subset selective search also occurs when both sets are presented simultaneously but differ in color. The aim of the present study was to investigate how numbers of irrelevant and relevant elements contribute to preview search in the absence and presence of a color difference between subsets. In two experiments it was demonstrated that a preview reduced the influence of the number of irrelevant elements in the absence but not in the presence of a color difference between subsets. In the presence of a color difference, a preview lowered the effect of the number of relevant elements but only when the target was defined by a unique feature within the relevant set (Experiment 1); when the target was defined by a conjunction of features (Experiment 2), search efficiency as a function of the number of relevant elements was not modulated by a preview. Together the results are in line with the idea that subset selective search is based on different simultaneously operating mechanisms.