The cost of being watched: Stroop interference increases under concomitant eye contact

Current models in social neuroscience advance that eye contact may automatically recruit cognitive resources. Here, we directly tested this hypothesis by evaluating the distracting strength of eye contact on concurrent visual processing in the well-known Stroop’s paradigm. As expected, participants showed stronger Stroop interference under concomitant eye contact as compared to closed eyes. Two control experiments allowed ruling out low-level account of this effect as well as non-specific effect of the presence of open eyes. This suggests that refraining from processing eye contact is actually as difficult as refraining from word reading in the Stroop task. Crucially, the eye contact effect was obtained while gaze was not under the direct focus of attention and the participants were faced with another powerful distracter (the incongruent word) in the task at hand. Thus, there is a cost of being watched even in circumstances where the processing of direct gaze is strongly disfavored. The present results emphasize the crucial status of eye contact in human cognition.     

Children's ability to distinguish between enjoyment and non‐enjoyment smiles

Children's ability to distinguish between enjoyment and non‐enjoyment smiles was investigated by presenting participants with short video excerpts of smiles. Enjoyment smiles differed from non‐enjoyment smiles by greater symmetry and by appearance changes produced in the eye region by the Cheek Raiser action. The results indicate that 6‐ and 7‐year‐old children have the abilities to detect these differences and are able to interpret them with above chance‐level accuracy. Sensitivity was higher for the symmetry of the smiles than for the appearance changes produced in the eye region and improved in later childhood. Copyright © 2009 John Wiley & Sons, Ltd.     

Controlling low-level image properties: The SHINE toolbox

Visual perception can be influenced by top-down processes related to the observer’s goals and expectations, as well as by bottom-up processes related to low-level stimulus attributes, such as luminance, contrast, and spatial frequency. When using different physical stimuli across psychological conditions, one faces the problem of disentangling the contributions of low- and high-level factors. Here, we make available the SHINE (spectrum, histogram, and intensity normalization and equalization) toolbox for MATLAB, which we have found useful for controlling a number of image properties separately or simultaneously. The toolbox features functions for specifying the (rotational average of the) Fourier amplitude spectra, for normalizing and scaling mean luminance and contrast, and for exact histogram specification optimized for perceptual visual quality. SHINE can thus be employed for parametrically modifying a number of image properties or for equating them across stimuli to minimize potential low-level confounds in studies on higher level processes.     

Acquisition of Reading and Intellectual Development Disorder

Journal of Psycholinguistic Research - We propose a review of the literature of the studies investigating reading acquisition in intellectual deficiency (ID), with particular focus on the...     

The Montreal Affective Voices: A validated set of nonverbal affect bursts for research on auditory affective processing

The Montreal Affective Voices consist of 90 nonverbal affect bursts corresponding to the emotions of anger, disgust, fear, pain, sadness, surprise, happiness, and pleasure (plus a neutral expression), recorded by 10 different actors (5 of them male and 5 female). Ratings of valence, arousal, and intensity for eight emotions were collected for each vocalization from 30 participants. Analyses revealed high recognition accuracies for most of the emotional categories (mean of 68%). They also revealed significant effects of both the actors' and the participants' gender: The highest hit rates (75%) were obtained for female participants rating female vocalizations, and the lowest hit rates (60%) for male participants rating male vocalizations. Interestingly, the mixed situations--that is, male participants rating female vocalizations or female participants rating male vocalizations--yielded similar, intermediate ratings. The Montreal Affective Voices are available for download at vnl.psy.gla.ac.uk/ (Resources section).     

On the origins of age‐of‐acquisition effects in the perception of printed words

Children from different grades were tested in a lexical decision task. Word‐stimuli consisted of words acquired in their respective grades, and in grades previous to their own. The results showed that the proportion of errors for newly acquired words increased steadily with grade (i.e. first graders made fewer errors with words of grade one than fifth graders with words of grade five). However, the proportion of errors for words acquired in a given grade remained constant throughout the following grades (fifth graders made as many errors with words acquired in grade one as first graders did). These results indicate that the strong impact that age‐ or order‐of‐acquisition of words has on the way words will be recognized is in place at a very young age.     

Children's and adolescents' perception of the authenticity of smiles

Recently, Thibault and colleagues described the Duchenne marker as a cultural dialect for the perception of smile authenticity. The current study had the goal to follow up on this finding and to investigate the cues that French Canadian children use to evaluate the authenticity of smiles from members of three ethnic groups. The authenticity of six smiles differing in intensity and presence of orbicularis oculi (Duchenne marker) was rated by 1206 children from 4 to 17 years of age. No differences were found as a function of encoder group. All children perceived medium Duchenne smiles as more authentic than equally intense medium non-Duchenne smiles. Furthermore, results suggest a decrease in the reliance on intensity across the age span. Younger children use the intensity marker along the whole continuum to infer authenticity. In contrast, older children (14- to 17-year-olds) rated all smiles that did not contain the Duchenne marker as roughly equally low in authenticity.     

Conditional Reinforcers and Informative Stimuli in A Constant Environment

Five pigeons responded on steady-state concurrent variable-interval variable-interval schedules of food presentation in which half of the foods were removed and replaced with nonfood stimuli. Across conditions, the stimuli were either paired or unpaired with food, and the correlation between the ratio of food deliveries on the two alternatives and the ratio of nonfood stimuli was either −1, 0, or +1. Neither the pairing of stimuli with food, nor the correlation between stimuli and food, affected generalized-matching performance, but paired stimuli had a demonstrable effect at a local level of analysis. This effect was independent of the food–stimulus correlation. These results differ from results previously obtained in a frequently changing environment. We attribute this difference in results to differences in the information value of response-contingent stimuli in frequently changing versus relatively constant environments, as well as to differences between forward pairing and simultaneous pairing of the stimuli with food.     

Attentional and anatomical considerations for the representation of simple stimuli in visual short-term memory: evidence from human electrophysiology

Observers encoded the spatial arrangement of two or three horizontal line segments relative to a square frame presented for 150 ms either in left or right visual field and either above or below the horizontal midline. The target pattern was selected on the basis of colour (red vs. green) from an equivalent distractor pattern in the opposite left–right visual hemifield. After a retention interval of 450 or 650 ms a test pattern was presented at fixation. The task was to decide whether the test was the same as the encoded pattern or different. Selection of the to-be-memorised pattern produced an N2pc response that was not influenced by the number of line segments nor by the length of the retention interval, but that was smaller in amplitude for patterns presented in the upper visual field compared with patterns presented in the lower visual field. A sustained posterior contralateral negativity (SPCN) followed the N2pc. The SPCN was larger for patterns with three line segments than for two, was larger for patterns encoded from lower visual field than from upper visual field, and returned to baseline sooner for the shorter retention interval than for the longer interval. These results, and others, provide an interesting and complex pattern of similarities and differences between the N2pc and SPCN, consistent with the view that N2pc reflects mechanisms of attentional selection whereas the SPCN reflects maintenance in visual short-term memory.     

Common Genetic but Specific Environmental Influences for Aggressive and Deceitful Behaviors in Preadolescent Males

Although both aggressive (AGG) and deceitful behaviors (DEC) are symptoms of childhood conduct problems, few studies have examined common vs. specific etiological influences. Early intervention is encouraged for conduct problems and findings from genetically informative studies can suggest whether interventions should focus on conduct problems in general or groupings of conduct problems more specifically. Twin model-fitting analyses were conducted on same and different teacher ratings of AGG and DEC for 872 9-year old male twin pairs. Common genetic influences were found to underlie the susceptibility for both AGG and DEC. The same teacher ratings resulted in somewhat higher heritability estimates than different teacher ratings. Results also indicated stronger environmental effects for DEC as compared with AGG, with a significant shared environmental component for same teachers and a substantial non-shared environmental component for different teachers. Our data suggest that AGG and DEC share risk genes and environmental factors may differentiate these two types of conduct problems. Characterizing these specific environmental factors may be useful when developing interventions.