Second-order mappings in grapheme–color synesthesia

Typically, the search for order in grapheme–color synesthesia has been conducted by looking at the frequency of certain letter–color associations. Here, we report stronger associations when second-order similarity mappings are examined—specifically, mappings between the synesthetic colors of letters and letter shape, frequency, and position in the alphabet. The analyses demonstrate that these relations are independent of one other. More strikingly, our analyses show that each of the letter–color mappings is restricted to one dimension of color, with letter shape and ordinality linked to hue, and letter frequency linked to luminance. These results imply that synesthetic associations are acquired as the alphabet is learned, with associations involving letter shape, ordinality, and frequency being made independently and idiosyncratically. Because these mappings of similarity structure between domains (letters and colors) are similar to those found in numerous other cognitive and perceptual domains, they imply that synesthetic associations operate on principles common to many aspects of human cognition.     

Biases and regularities of grapheme–colour associations in Japanese nonsynaesthetic population

Associations between graphemes and colours in a nonsynaesthetic Japanese population were investigated. Participants chose the most suitable colour from 11 basic colour terms for each of 40 graphemes from the four categories of graphemes used in the Japanese language (kana characters, English alphabet letters, and Arabic and kanji numerals). This test was repeated after a three-week interval. In their responses, which were not as temporally consistent as those of grapheme–colour synaesthetes, participants showed biases and regularities that were comparable to those of synaesthetes reported in past studies. Although it has been believed that only synaesthetes, and not nonsynaesthetes, tended to associate graphemes with colours based on grapheme frequency, Berlin and Kay's colour typology, and colour word frequency, participants in this study tended in part to associate graphemes with colours based on the above factors. Moreover, participants that were nonsynaesthetes tended to associate different graphemes that shared sounds and/or meanings (e.g., Arabic and kanji numerals representing the same number) with the same colours, which was analogous to the findings in Japanese synaesthetes. These results support the view that grapheme–colour synaesthesia might have its origins in cross-modal association processes that are shared with the general population.     

Metacontrast masking is processed before grapheme–color synesthesia

We investigated the physiological mechanism of grapheme–color synesthesia using metacontrast masking. A metacontrast target is rendered invisible by a mask that is delayed by about 60 ms; the target and mask do not overlap in space or time. Little masking occurs, however, if the target and mask are simultaneous. This effect must be cortical, because it can be obtained dichoptically. To compare the data for synesthetes and controls, we developed a metacontrast design in which nonsynesthete controls showed weaker dichromatic masking (i.e., the target and mask were in different colors) than monochromatic masking. We accomplished this with an equiluminant target, mask, and background for each observer. If synesthetic color affected metacontrast, synesthetes should show monochromatic masking more similar to the weak dichromatic masking among controls, because synesthetes could add their synesthetic color to the monochromatic condition. The target–mask pairs used for each synesthete were graphemes that elicited strong synesthetic colors. We found stronger monochromatic than dichromatic U-shaped metacontrast for both synesthetes and controls, with optimal masking at an asynchrony of 66 ms. The difference in performance between the monochromatic and dichromatic conditions in the synesthetes indicates that synesthesia occurs at a later processing stage than does metacontrast masking.     

The “idealized individual” interpretation of individual differences in multidimensional scaling

It is shown that several variants of the Tucker-Messick points of view procedure are interpretable in terms of their idealized individual concepts. It is contended that the main function of the method is that it allows the computation ofseveral vectors of mean judgments instead of only one and that each of these may be used to stand for the actual judgments of a subgroup of subjects. Vectors that do not correspond to the judgments of any subjects are to be avoided. It is alleged that Ross's interpretation of points of view is quite different from that intended by Tucker and Messick.The preparation of this paper was supported in part by Contract Nonr-228(32) between the Office of Navel Research and the University of Southern California.     

Grapheme–color synesthesia can enhance immediate memory without disrupting the encoding of relational cues

Previous evidence has suggested that grapheme–color synesthesia can enhance memory for words, but little is known about how these photisms cue retrieval. Often, the encoding of specific features of individual words can disrupt the encoding of ordered relations between words, resulting in an overall decrease in recall accuracy. Here we show that the photisms arising from grapheme–color synesthesia do not function like these item-specific cues. The influences of high and low word frequency on the encoding of ordered relations and the accuracy of immediate free recall were compared across a group of 10 synesthetes and 48 nonsynesthetes. The main findings of Experiment 1 showed that the experience of synesthesia had no adverse effect on the encoding of ordered relations (as measured by input–output correspondence); furthermore, it enhanced recall accuracy in a strictly additive fashion across the two word frequency conditions. Experiment 2 corroborated these findings by showing that the synesthetes only outperformed the nonsynesthetes when the materials involved words and letters, not when they involved digits and spatial locations. Altogether, the present findings suggest that synesthesia can boost immediate memory performance without disrupting the encoding of ordered relations.     

The relationship between color–object associations and color preference: Further investigation of ecological valence theory

Ecological valence theory (EVT; Palmer & Schloss, Proceedings of the National Academy of Sciences 107:8877–8882, 2010) proposes that color preferences are due to affective responses to color-associated objects: That is, people generally like colors to the degree that they like the objects associated with those colors. Palmer and Schloss found that the average valence of objects associated with a color, when weighted by how well the objects matched the color (weighted affective valence estimates: WAVE) explained 80% of the variation in preference across colors. Here, we replicated and extended Palmer and Schloss’s investigation to establish whether color–object associations can account for sex differences in color preference and whether the relationship between associated objects and color preference is equally strong for males and females. We found some degree of sex specificity to the WAVEs, but the relationship between WAVE and color preference was significantly stronger for males than for females (74% shared variance for males, 45% for females). Furthermore, analyses identified a significant inverse relationship between the number of objects associated with a color and preference for the color. Participants generally liked colors associated with few objects and disliked colors associated with many objects. For the sample overall and for females alone, this association was not significantly weaker than the association of the WAVE and preference. The success of the WAVE at capturing color preference was partly due to the relationship between the number of associated objects and color preference. The findings identify constraints of EVT in its current form, but they also provide general support for the link between color preference and color–object associations.     

Does color synesthesia pose a paradox for early-selection theories of attention?

Abstract— P.M. is a synesthete who experiences colors when viewing alphanumeric symbols. Her search for a target differing from distractors by a synesthetic color feature takes the form of a pop-out search. Thus, it would seem that synesthesia can occur preattentively. However, discrepancies between the regression functions of response times observed in target-present trials and target-absent trials, and the fact that fast response times occur only when the target is within a few degrees of visual angle from fixation, indicate that P.M.'s synesthesia does not occur preattentively, but rather is within the focus of attention. We conclude that synesthesia is a genuine perceptual phenomenon that can have substantial influence on visual processing.     

Do individual differences in intolerance of uncertainty affect health monitoring?

Researchers have postulated that individual differences in intolerance of uncertainty (IU) may affect people's health behaviours. Study 1 (N?=?147 university students) supports this proposition showing that higher IU is associated with higher monitoring (seeking threat-relevant information). Study 2 (N?=?117 university students) experimentally manipulated IU to ensure that the association is not due to other related constructs such as anxiety or worry. Results show that inducing high IU led to increased monitoring as reflected by higher scores on an index of monitoring measures. Wanting information about the health threat in order to reduce their uncertainty was an independent predictor of monitoring and did not mediate the relationship between IU and monitoring. Findings suggest that high IU induces people to increase their monitoring; an adaptive strategy when the health threat can be reduced through this behaviour.     

The personality triad in balance: Multidimensional individual differences in situation–behavior profiles

A new methodology is proposed to study the full personality triad including persons, situations, and responses. It is based on a model of the structural mechanism underlying behavioral data in terms of eliciting power of situations, response thresholds, as well as quantitative and/or qualitative individual differences. The model is aimed at conceptually clarifying the personality triad and makes it possible to derive individual differences in situation–behavior profiles (or behavioral signatures) starting from empirically gathered person-by-situation-by-response data. It is particularly well-suited to capture multidimensional individual differences—implying complex person by situation and/or person by response interactions—and to examine the psychological mechanisms underlying them. In an application to anger-in and anger-out in interpersonal frustrating situations, three person types were derived that were characterized in terms of distinctive behavioral signatures. Part of the differences in behavioral signatures could be explained in terms of hostile encoding and hostile expectancy processes.     

Variability of color choice in the Lüscher Color Test--sex differences

In this preliminary investigation of variability of responses on the Lüscher Color Test, subjects were 567 volunteers administered the test twice with a 10-min. interval between them. Two hypotheses were tested: (a) that variability of responses attests to the personality of the respondent (tested by the relations of variability and MMPI scale scores), and (b) variability of responses is based on learning the test's content. As such, men's scores should be more variable than women's. Analysis showed that variability was not correlated with scores for personality on the MMPI scales. Men's scores are more variable than women's, but only until age 45.     

Internalization of children’s problem solving and individual differences in learning

The purpose of this study was to identify qualitative distinctions of six- to seven-year-old children’s learning that could be attributed to differences in their cross-domain levels of internalization of problem-solving activity. Two such distinctions were found: (a) the highest level (symbolic, visual-imagery, or visual-motor) at which the children were able to understand the algorithm for a new problem-solving process; and (b) the highest level (symbolic, visual-imagery, or visual-motor) at which they were able to perform a new problem-solving process after understanding its algorithm. These distinctions were coincident and stable for a particular child and were related to that child’s ability to transfer new knowledge.     

Increased distractibility in schizotypy: Independent of individual differences in working memory capacity?

Individuals with schizophrenia typically show increased levels of distractibility. This has been attributed to impaired working memory capacity (WMC), since lower WMC is typically associated with higher distractibility, and schizophrenia is typically associated with impoverished WMC. Here, participants performed verbal and spatial serial recall tasks that were accompanied by to-be-ignored speech tokens. For the few trials wherein one speech token was replaced with a different token, impairment was produced to task scores (a deviation effect). Participants subsequently completed a schizotypy questionnaire and a WMC measure. Higher schizotypy scores were associated with lower WMC (as measured with operation span, OSPAN), but WMC and schizotypy scores explained unique variance in relation to the mean magnitude of the deviation effect. These results suggest that schizotypy is associated with heightened domain-general distractibility, but that this is independent of its relationship with WMC.     

Who uses base rates andP(D/∼H)? An analysis of individual differences

In two experiments, involving over 900 subjects, we examined the cognitive correlates of the tendency to viewP(D/～H) and base rate information as relevant to probability assessment. We found that individuals who viewedP(D/～H) as relevant in a selection task and who used it to make the proper Bayesian adjustment in a probability assessment task scored higher on tests of cognitive ability and were better deductive and inductive reasoners. They were less biased by prior beliefs and more datadriven on a covariation assessment task. In contrast, individuals who thought that base rates were relevant did not display better reasoning skill or higher cognitive ability. Our results parallel disputes about the normative status of various components of the Bayesian formula in interesting ways. It is argued that patterns of covariance among reasoning tasks may have implications for inferences about what individuals are trying to optimize in a rational analysis (J. R. Anderson, 1990, 1991).     

Developing number–space associations: SNARC effects using a color discrimination task in 5-year-olds

Human adults’ numerical representation is spatially oriented; consequently, participants are faster to respond to small/large numerals with their left/right hand, respectively, when doing a binary classification judgment on numbers, known as the SNARC (spatial–numerical association of response codes) effect. Studies on the emergence and development of the SNARC effect remain scarce. The current study introduces an innovative new paradigm based on a simple color judgment of Arabic digits. Using this task, we found a SNARC effect in children as young as 5.5 years. In contrast, when preschool children needed to perform a magnitude judgment task necessitating exact number knowledge, the SNARC effect started to emerge only at 5.8 years. Moreover, the emergence of a magnitude SNARC but not a color SNARC was linked to proficiency with Arabic digits. Our results suggest that access to a spatially oriented approximate magnitude representation from symbolic digits emerges early in ontogenetic development. Exact magnitude judgments, on the other hand, rely on experience with Arabic digits and, thus, necessitate formal or informal schooling to give access to a spatially oriented numerical representation.     

Analysis of individual differences in multidimensional scaling via an n-way generalization of “Eckart-Young” decomposition

An individual differences model for multidimensional scaling is outlined in which individuals are assumed differentially to weight the several dimensions of a common “psychological space”. A corresponding method of analyzing similarities data is proposed, involving a generalization of “Eckart-Young analysis” to decomposition of three-way (or higher-way) tables. In the present case this decomposition is applied to a derived three-way table of scalar products between stimuli for individuals. This analysis yields a stimulus by dimensions coordinate matrix and a subjects by dimensions matrix of weights. This method is illustrated with data on auditory stimuli and on perception of nations.     

How can individual differences in autobiographical memory distributions of older adults be explained?

The reminiscence bump phenomenon has frequently been reported for the recall of autobiographical memories. The present study complements previous research by examining individual differences in the distribution of word-cued autobiographical memories. More importantly, we introduce predictor variables that might account for individual differences in the mean (location) and the standard deviation (scale) of individual memory distributions. All variables were derived from different theoretical accounts for the reminiscence bump phenomenon. We used a mixed location-scale logitnormal model, to analyse the 4602 autobiographical memories reported by 118 older participants. Results show reliable individual differences in the location and the scale. After controlling for age and gender, individual proportions of first-time experiences and individual proportions of positive memories, as well as the ratings on Openness to new Experiences and Self-Concept Clarity accounted for 29% of individual differences in location and 42% of individual differences in scale of autobiographical memory distributions. Results dovetail with a life-story account for the reminiscence bump which integrates central components of previous accounts.     

Extraversion predicts individual differences in women’s face preferences

Extraversion is positively associated with various indices of women’s mate quality (e.g., facial symmetry and attractiveness). Since such indices are thought to predict variation in women’s preferences for masculine men, we investigated the relationships between each of the ‘Big 5’ personality factors and women’s preferences for facial masculinity. Extraversion, but not the other four personality factors, was positively correlated with women’s preferences for masculinity in men’s, but not women’s, faces. Additionally, extraversion mediated the positive relationship between women’s self-rated attractiveness and their preferences for masculinity in men’s faces, suggesting that extraversion may play a role in condition-dependent mate preferences. Unexpectedly, openness to experience was associated with women’s preferences for femininity in faces of both sexes and this association was independent of that between extraversion and women’s preferences for masculine men. This is the first study that we know of to implicate personality traits in individual differences in women’s preferences for masculine men.     

Is EEG α a consistent measure of individual differences?

Integrated EEG activity in the 9–13 Hz band was recorded from 24 Ss under three experimental conditions (Relaxation, Attentive Listening and Mental Arithmetic) in two separate sessions. Analysis of components of variance due to persons and the interactions of persons with sessions and with conditions pointed to the importance of the persons × conditions interaction. It is concluded that under typically employed conditions of testing EEG α is not a consistent measure of individual differences.