Hemispheric predominance assessment of phonology and semantics: a divided visual field experiment

The aim of the present behavioural experiment was to evaluate the most lateralized among two phonological (phoneme vs. rhyme detection) and the most lateralized among two semantic ("living" vs. "edible" categorization) tasks, within the dominant hemisphere for language. The reason of addressing this question was a practical one: to evaluate the degree of the hemispheric lateralization for several language tasks, by using the divided visual presentation of stimuli, and then choose the most lateralized semantic and phonological for mapping language in patients by using fMRI in future studies. During the divided visual field experiment by using words (semantic tasks) and pseudo-words (phonological tasks) as stimuli, thirty-nine right-handed participants were examined. Our results have shown that all tasks were significantly left hemisphere lateralized. Furthermore, the rhyme was significantly more lateralized than phoneme detection and "living" was significantly more lateralized than "edible" categorization. The rhyme decision and "living" categorization will be used in future fMRI studies for assessing hemispheric predominance and cerebral substrate for semantics and phonology in patients. Our results also suggest that the characteristics of stimuli could influence the degree of the hemispheric lateralization (i.e., the emotional charge of stimuli for words and the position of the phoneme to be detected, for pseudo-words).     

Exogenous attention differentially modulates the processing of categorical and coordinate spatial relations

Carrasco and her colleagues have suggested that exogenous attention reduces the size of receptive fields at an attended location (Gobell & Carrasco, 2005; Yeshurun & Carrasco, 1998, 2000). Based on the hypothesis that categorical and coordinate spatial relations are more efficiently processed by smaller and larger receptive fields, respectively, we predicted that exogenous attention would be more beneficial to the processing of categorical spatial relations than coordinate spatial relations while it would disrupt the processing of coordinate spatial relations. To test these hypotheses, participants were tested using a variant of Posner's (1980) attentional cueing paradigm. Exogenous attention produced larger facilitative effects on categorical spatial processing than on coordinate spatial processing at a short cue-target stimulus onset asynchrony (100 ms, Experiment 1, N = 28), and this result was replicated regardless of cue size in Experiment 2 (N = 24). When the coordinate judgment was sufficiently difficult, exogenous attention disrupted the processing of coordinate spatial relations (Experiment 3, N = 28). These findings indicate that exogenous attention can differentially modulate the processing of categorical and coordinate spatial relations.     

Categorization and cognitive deficits in compulsive hoarding

According to the cognitive-behavioural model of compulsive hoarding, information-processing deficits in the areas of attention, memory, decision-making, and categorization contribute to hoarding behaviour. The purpose of the current study was to examine whether individuals with compulsive hoarding exhibited impairment on executive functioning and categorization tasks. Three groups of participants were recruited (N = 60): individuals with compulsive hoarding syndrome, individuals with an Axis I mood or anxiety disorder, and non-clinical control participants. All participants completed self-report measures of cognitive difficulties, neuropsychological tests of executive functioning and decision-making, and four categorization tasks. Results suggested that hoarding participants reported more cognitive failures and more problems with attention and decision-making than non-clinical control participants. In addition, hoarding participants performed worse than both control groups on the Stockings of Cambridge (SOC), a neuropsychological test of planning ability, and were slower and more anxious during a categorization task. These findings suggest that specific deficits in executive functioning may be associated with the difficulties hoarding patients have organizing their possessions.     

First graders' literacy and self-regulation gains: The effect of individualizing student instruction

We examined the effect of individualizing student instruction (ISI; N = 445 students, 46 classrooms) on first graders' self-regulation gains compared to a business-as-usual control group. Self-regulation, conceptualized as a constellation of executive skills, was positively associated with academic development. We hypothesized that the ISI intervention's emphasis on teacher planning and organization, classroom management, and the opportunity for students to work independently and in small groups would promote students' self-regulation. We found no main effect of ISI on self-regulation gains. However, for students with weaker initial self-regulation, ISI was associated with greater self-regulation gains compared to peers in control classrooms. The ISI effect on self-regulation was greater when the intervention was more fully implemented.     

Chess as a Behavioral Model for Cognitive Skill Research: Review of Blindfold Chess by Eliot Hearst and John Knott

This multifaceted work on chess played without sight of the pieces is a sophisticated psychologist's examination of this topic and of chess skill in general, including a detailed and comprehensive historical account. This review builds on Hearst and Knott's assertion that chess can provide a uniquely useful model for research on several issues in the area of cognitive skill and imagery. A key issue is the relationship between viewing a stimulus and mental imagery in the light of blindfold chess masters' consistent reports that they do not use or have images. This review also proposes a methodology for measuring and quantifying an individual's skill shortfall from a theoretical maximum. This methodology, based on a 1951 proposal by Claude Shannon, is applicable to any choice situation in which all the available choices are known. The proposed “Proficiency” measure reflects the equivalent number of “yes—no” questions that would have been required to arrive at a best choice, considering also the time consumed. As the measure provides a valid and nonarbitrary way to compare different skills and the effects of different independent variables on a given skill, it may have a wide range of applications in cognitive skill research, skill training, and education.     

Finding Creativity in an Artificial Artist

Creativity is an important component of human intelligence, and imbuing artificially intelligent systems with creativity is an interesting challenge. In particular, it is difficult to quantify (or even qualify) creativity. Recently, it has been suggested that conditions for attributing creativity to a system include: appreciation, imagination, and skill. We demonstrate and describe an original computer system (called DARCI) that is designed to produce images through creative means. We present methods for evaluating DARCI and other artificially creative systems with respect to appreciation, imagination, and skill, and use these methods to show that DARCI is arguably a creative system.     

N400 and P600 or the Role of the ERP Correlates in Sentence Comprehension: Some Applications to the Italian Language

In the present study, event-related brain potentials (ERPs) were applied to the study of language comprehension in the Italian language. The ERPs were recorded from 10 electrodes while the participants read (Experiment 1) or listened (Experiment 2) to sentences containing semantic or syntactic anomalies. Final words that were inconsistent with the sentence context elicited a negative wave at about 400 ms poststimulus that was more concentrated in the posterior sites of the scalp, whereas final words that were incongruous with the grammatical structure (subject-verb nonagreement) elicited a positive wave at about 600 ms poststimulus that was homogeneously distributed on the scalp. The authors found no differences based on the perceptual modality of the stimulus (visual or auditory), nor did they find different ERP correlates as a function of task relevance (explicit-implicit task induction). The available evidence indicated that the ERP response to semantic anomalies was at least partially distinct from the ERP response to syntactic anomalies, and that a syntactic parser is a plausible process included in sentence comprehension. The two semantic and syntactic effects appear as automatic processes of the decoding of the anomalies and also modality-independent processes. Cross-linguistic applications are considered in the general discussion.     

Sampling Methods for Identifying Differences in Source Reliability

This study explored observer performance in using across-trial and within-trial variability information to weight sources based on reliability. Three trained observers performed a multi-element, visual signal-detection task under 3 block-type conditions: a fixed block condition and 2 random conditions. In the fixed block condition, the observers had both within- and across-trial variability information to identify differences in source reliability. The random conditions eliminated the across-trial information, leaving only within-trial variability information in 1 case and neither within- nor across-trial variability information in another case. There was a significant block-type effect. Observers could use differences in across-trial variability of individual sources to assign weights. Although there was a difference in the weights assigned to reliable and unreliable sources in the partial-random condition (in which within-trial variability information was available), only 1 participant showed a significant difference in the weight assignment relative to the full-random condition. Thus, altogether, observers were not very efficient at using within-trial variability to weight sources accordingly.     

Visual-Field Bias in the Judgment of Facial Expression of Emotion

The left and right hemispheres of the brain are differentially related to the processing of emotions. Although there is little doubt that the right hemisphere is relatively superior for processing negative emotions, controversy exists over the hemispheric role in the processing of positive emotions. Eighty right-handed normal male participants were examined for visual-field (left-right) differences in the perception of facial expressions of emotion. Facial composite (RR, LL) and hemifacial (R, L) sets depicting emotion expressions of happiness and sadness were prepared. Pairs of such photographs were presented bilaterally for 150 ms, and participants were asked to select the photographs that looked more expressive. A left visual-field superiority (a right-hemisphere function) was found for sad facial emotion. A hemispheric advantage in the perception of happy expression was not found.     

A Question of Foot Dominance

It is suggested that the popular definition of foot dominance (i.e., the limb preferred to execute a manipulative or mobilizing action while the other [nondominant] foot provides stabilizing support, e.g., kicking a ball) be reconsidered in light of understanding the functional characteristics of footedness and selected theoretical explanations. Relevance to future research designs and assessment methodology is discussed.