Executive control within strategic deception: a window on early cognitive development?

Recently it has been claimed that the difficulty young children have with tests of strategic deception may be due to limitations in executive control rather than lack of insight into mental concepts. In the studies reported here we asked how reducing the executive demands of one measure of strategic deception, the windows task (J. Russell, N. Mauthner, S. Sharpe, & T. Tidswell, 1991), would affect performance. Study 1 demonstrated that both providing an artificial response medium and having children play in partnership enabled 3-year-olds to adopt a successful strategy. Study 2 examined whether social or executive factors accounted for the good performance of children when they played in partnership. Study 3 ruled out the possibility that the effectiveness of the artificial media was a result of reducing social intimidation-the manipulations were effective even in the presence the opponent. These results argue for executive factors playing a substantial role in the development of strategic deception.     

Organizational justice and Black applicants' reactions to affirmative action

Using organizational justice as a guiding framework, the authors studied perceptions of affirmative action programs by presumed beneficiaries. Three conceptual issues were addressed: (a) the content of different affirmative action plans; (b) the 3-way interaction among distributive, procedural, and interactional justice; and (c) the distinction between outcome favorability and distributive justice. These ideas were tested with a sample of Black engineering students who responded to 1 of 6 plans. Participants distinguished among the various plans, with some policies being viewed as more fair than others. In addition, a 3-way interaction among the 3 types of organizational justice was observed. Specifically, the 2-way interaction between distributive and interactional fairness was only significant when procedural justice was low. Implications for organizational justice and for the design of affirmative action programs are discussed.     

A systematic evaluation of food textures to decrease packing and increase oral intake in children with pediatric feeding disorders

This study examined packing (pocketing or holding accepted food in the mouth) in 3 children who were failing to thrive or had inadequate weight gain due to insufficient caloric intake. The results of an analysis of texture indicated that total grams consumed were higher when lower textured foods were presented than when higher textured foods were presented. The gram intake was related directly to levels of packing. That is, high levels of packing were associated with higher textured foods and low gram intake, and low levels of packing were associated with lower textured foods and high gram intake. All participants gained weight when texture of foods was decreased. Packing remained low during follow-up for 2 participants even when the texture of food was increased gradually over time. These data are discussed in relation to avoidance, response effort, and skill deficit.     

The distribution and development of handedness for manual gestures in captive chimpanzees (Pan troglodytes)

This article describes the distribution and development of handedness for manual gestures in captive chimpanzees. Data on handedness for unimanual gestures were collected in a sample of 227 captive chimpanzees. Handedness for these gestures was compared with handedness for three other measures of hand use: tool use, reaching, and coordinated bimanual actions. Chimpanzees were significantly more right-handed for gestures than for all other measures of hand use. Hand use for simple reaching at 3 to 4 years of age predicted hand use for gestures 10 years later. Use of the right hand for gestures was significantly higher when gestures were accompanied by a vocalization than when they were not. The collective results suggest that left-hemisphere specialization for language may have evolved initially from asymmetries in manual gestures in the common ancestor of chimpanzees and humans, rather than from hand use associated with other, non-communicative motor actions, including tool use and coordinated bimanual actions, as has been previously suggested in the literature.     

Medial temporal and prefrontal lobe activation during verbal encoding following glucose ingestion in schizophrenia: A pilot fMRI study

Verbal declarative memory is one of the most reliably impaired cognitive functions in schizophrenia. Important issues are whether the problem is reversible, and which brain regions underlie improvement. We showed previously that glucose administration improved declarative memory in patients with schizophrenia, and sought in this pilot study to identify whether glucose affects the location or degree of activation of brain regions involved in a verbal encoding task. Seven clinically stable and medicated patients with schizophrenia or schizoaffective disorder, who showed deficits on a clinical test of memory, participated in the study. Subjects served as their own controls in a double-blind, crossover protocol that consisted of two sessions about a week apart. In each session, subjects ingested a beverage flavored with lemonade that contained 50 g of glucose on one occasion, and saccharin on the other. Blood glucose was measured before and 15, 50, and 75 min after ingestion. After ingesting the beverage, they performed a verbal encoding task while undergoing brain functional magnetic resonance imaging. The results showed significantly greater activation of the left parahippocampus during novel sentence encoding in the glucose condition, compared to the saccharin condition, despite no change in memory performance. A trend towards greater activation of the left dorsolateral prefrontal cortex (p<.07) was also evident in the glucose condition. These pilot findings emphasize the sensitivity of both the medial temporal and prefrontal regions to effects of glucose administration during encoding, and are consistent with the hypothesis that these regions also participate in declarative memory improvements following glucose administration.