Visual habituation at five months: short-term reliability of measures obtained with a new polynomial regression criterion

Using a new polynomial regression criterion, the authors investigated empirically the short-term reliability of infants' visual habituation measures. Twenty-one 5-month-old infants were tested twice with a 1-day interval. Results revealed many reliable habituation measures, a reliable reaction to novelty measure, and a new reliable measure of interest. The 2nd-order polynomial regression criterion probably produced this improvement because it uses all of the available looking time data.     

Facial Morphology and Children's Categorization of Facial Expressions of Emotions: A Comparison Between Asian and Caucasian Faces

The effects of Asian and Caucasian facial morphology were examined by having Canadian children categorize pictures of facial expressions of basic emotions. The pictures were selected from the Japanese and Caucasian Facial Expressions of Emotion set developed by D. Matsumoto and P. Ekman (1989). Sixty children between the ages of 5 and 10 years were presented with short stories and an array of facial expressions, and were asked to point to the expression that best depicted the specific emotion experienced by the characters. The results indicated that expressions of fear and surprise were better categorized from Asian faces, whereas expressions of disgust were better categorized from Caucasian faces. These differences originated in some specific confusions between expressions.     

Pupil diameter measurement errors as a function of gaze direction in corneal reflection eyetrackers

Pupil dilation is a useful, noninvasive technique for measuring the change in cognitive load. Since it is implicit and nonverbal, it is particularly useful with preverbal or nonverbal participants. In cognitive psychology, pupil dilation is most often measured by corneal reflection eye-tracking devices. The present study investigates the effect of gaze position on pupil size estimation by three common eye-tracking systems. The task consisted of a simple object pursuit situation, as a sphere rotated around the display screen. Systematic errors of pupil size estimation were found with all three systems. Implications for task-elicited pupillometry, especially for gaze-contingent studies such as object tracking or reading, are discussed.     

Peer-facilitated cognitive dissonance versus healthy weight eating disorders prevention: A randomized comparison

Research supports the efficacy of both cognitive dissonance (CD) and healthy weight (HW) eating disorders prevention, and indicates that CD can be delivered by peer-facilitators, which facilitates dissemination. This study investigated if peer-facilitators can deliver HW when it is modified for their use and extended follow-up of peer-facilitated CD as compared to previous trials. Based on pilot data, we modified HW (MHW) to facilitate peer delivery, elaborate benefits of the healthy-ideal, and place greater emphasis on consuming nutrient dense foods. Female sorority members (N = 106) were randomized to either two 2-h sessions of CD or MHW. Participants completed assessment pre- and post-intervention, and at 8-week, 8-month, and 14-month follow-up. Consistent with hypotheses, CD decreased negative affect, thin-ideal internalization, and bulimic pathology to a greater degree post-intervention. Both CD and MHW reduced negative affect, internalization, body dissatisfaction, dietary restraint, and bulimic pathology at 14 months.     

The “Poffenberger” and “Dimond” Paradigms: Interrelated Approaches to the Study of Interhemispheric Dynamics?

Brown and Jeeves (1993) found that an evoked potential estimate of interhemispheric transfer time, from the left to the right hemisphere, correlated negatively with a bilateral field advantage (BFA) in a response-choice letter matching task. We implemented a go no-go dot size matching task to determine whether the crossed-uncrossed difference (CUD) in reaction time, commission errors and omission errors (estimates of the “cost” of interhemispheric transfer) would correlate with BFAs in data from the same experiment and whether the type of decision (“same” versus “different”) would modulate the CUDs and/or BFAs. Sixteen normal right-handed subjects were tested. The CUDs were negatively correlated with the BFAs. Canonical correlation analysis of this set of relations was highly significant (r= .95). Estimates of left-to-right relay were far more strongly related to BFA (p= .0001) than were estimates of right-to-left relay (p= .03). “Same” decisions yielded a unilateral field advantage and “different” decisions a bilateral field advantage in omission error data, this crossed interaction reaching significance. More efficient interhemispheric relay favored BFAs, i.e., strongly suggesting in such cases an advantage of interhemispheric over intrahemispheric integration. This effect appeared to be markedly asymmetric. Furthermore, resource sharing within and between the hemispheres was a function of the “same” versus “different” dimensions of the decision to be made, especially in omission errors. The opposite dissociation occurred less markedly in the reaction times, this double dissociation reaching significance, revealing presence of a subtle speed–accuracy trade-off in interhemispheric dynamics.