Is anorexia nervosa a neuropsychological disease?

Evidence for central nervous system, and more particularly cortical, etiology of anorexia nervosa is reviewed. Topics covered are neuropsychiatric comorbidity, inheritance patterns, the neurobiology of body-image disturbance and of the eating function, perinatal and alcoholic insult to the brain, neurochemical and neuroelectric disturbance, anatomic and metabolic brain imaging, and neuropsychological impairment. It is concluded that there is indeed an important neuropsychological etiological dimension to anorexia nervosa. The profile most frequently associated with anorexia nervosa is right posterior hypometabolism, followed by right anterior hypermetabolism, both associated with right-sided abnormal electroencephalogram spiking. It is also proposed that bulimia consists of a positive neurological subtype and that restricting anorexia represents a negative neurological subtype. Priorities for further research into anorexia nervosa are specified to include twin adoption studies, brain electrical topography studies, postmortem histological studies, and experimentally inspired neuropsychological studies.     

STRATÉGIES COGNITIVES ET PROCESSUS D'AUTORÉGULATION CHEZ DES FAMILLES EN SITUATION DE RÉSOLUTION DE PROBLÈMES LOGIQUES*

The family is a fundamental learning environment for many basic skills such as the ability to solve everyday domestic problems. A lack of competence in this type of problem solving would expose the individual to more frustration and possibly create the conditions for greater aggression. Forty-two low SES families, each including an aggressive boy, were invited to the laboratory for a problem-solving session on two occasions, at an interval of two years. Subjects were asked to find four preset combinations of colours by systematic permutations of four colours using a computer. Three types of cognitive performance were examined: resolution strategies, autoregulation strategies and the success rate in finding the solution. Results showed that most of the families were consistent in their use of a non-systematic strategy. Although some improvement in planning is observed during the second testing, no other improvement in autoregulation strategies was observed. In general, families had a better rate of success in finding the solution in the second session. The low cognitive level of these families and its stability are discussed. Étant donné que la famille constitue un terrain privilégié d'apprentissage, l'aggressivité comportementale de certains enfants pourrait résider dans le peu d'opportunités offertes par leur famille d'apprendre à affronter les problèmes de la vie quotidienne d'une manière réfléchie. Quarante-deux familles de milieu socio-économique faible, dont un des enfants est à risque d'inadaptation sociale et dont les parents sont peu scolarisés, ont à résoudre un problème nécessitant l'intelligence logique et ce, à deux ans d'intervalle (T-1 et T-2). La tâche consite à résoudre un problème de permutations à quatre éléments et se présente sous la forme d'un jeu d'ordinateur. Le fonctionnement cognitif est examiné selon trois dimensions: les stratégies cognitivcs de résolution, les stratégies d'autorégulation exercées, sur la démarche cognitive et l'issue de la démarche cognitive. L'examen des stratégies cognitives révèle que la majorité des familles utilisent une approche non stratégique et que cette approche est maintenue aussi bien à l'intérieur d'une séance donnée que d'une séance à l'autre. Exception faite de l'amélioration relevée à la séance 2 quant au contrôle exercé par les familles sur le déroulement de leur démarche cognitive, aucun changement n'émerge sur les autres critères de l'autorégulation. Finalement, les familles obtiennent une meilleure performance à la deuxième séance. La discussion porte sur la relative stabilité du niveau de fonctionnement cognitif des familles ainsi que sur la pauvreté apparente de leur répertoire de schèmes.     

Recovery of performance during sleep following sleep deprivation in older normal and insomniac adult males

Groups of 12 normal and insomniac male subjects aged 55 to 71 yr. were sleep deprived for 64 hr. In both groups, the sleep loss was preceded by four baseline sleep nights and followed by four recovery nights. Reaction time, immediate recall, sleepiness, and body temperature were measured at approximately 2300, 0115, 0330, 0530, and 0800 during baseline, deprivation and recovery nights. Significant performance or mood differences were not found between the normal and insomniac males on any measure or at any testing period throughout the study. Performance of both groups declined characteristically during sleep loss while subjective sleepiness increased. As in young adults, degraded performance was restored by 8 hr. of recovery sleep. However, subjective sleepiness did not return to baseline levels until early in the second recovery night. It was concluded that chronic insomnia does not result in group performance deficits similar to those seen after chronic sleep loss; and the restorative function of sleep operates as efficiently in older insomniac subjects (who apparently have reduced need to sleep) as in older normal subjects.     

The influence of individual and family characteristics upon career aspirations of girls during childhood and adolescence

The term pioneer is used for girls aspiring to male-dominated careers. This longitudinal study assesses the career choices of 68 middle-class girls during childhood (8–13 years, Phase I) and again during adolescence (13–18 years, Phase II), and investigates the relation between pioneering career choice and personal and family characteristics. Subjects were originally selected for exposure vs nonexposure to exogenous hormones during pregnancy. In childhood, pioneers were somewhat older, were more often persistent tomboys, had higher IQs, and had parents with higher educational attainment. In adolescence, paternal education was the only variable that showed the same relation to career choice. Adolescent girls who had wanted to get married at the time of the childhood assessment were now less likely to choose pioneering careers. Adolescent pioneers also had higher educational aspirations than nonpioneers and less likely anticipated being married within ten years than nonpioneers. A number of statistically borderline relationships were also observed: pioneers had somewhat fewer older brothers than nonpioneers, less often came from homes in which traditional femininity was stressed, and more frequently had mothers who had worked outside the home throughout their daughters' school years than mothers of nonpioneers. Prenatal exposure to exogenous sex hormones was not related to career choice during either childhood or adolescence.     

Simulation study of a decision-making model of squash competition, phase two: Testing the model through the use of computer simulation

This study aims at verifying the inner validity and logic of a squash competition decision-making model through the use of computer simulation. The model defines the cognitive-decisional strategy of the defending player (D) when selecting a motor reaction in response to his opponent's shot. Computer simulation of the model was carried out on a PDP-10 computer using a recent version of UCI-LISP. Protocol analysis data pertaining to the nature of the information D processes when awaiting the attacking player's shot were fed into the simulation program in order to examine the extent to which the model can reproduce decisions reached in various defensive contexts. Simulation results reveal that the proposed model can account for a substantial part of the variation in the speed and accuracy of D's motor reaction in real sport situations. Several factors like time pressure, expectancies, uncertainty, recency and familiarity of the relationship between signal and response appear to affect D's motor response via the cognitive-decisional strategy employed by the defending player. Particular discrepancies observed between simulation results and decisions reached by expert players in specific defensive situations nevertheless indicate that the decision rule utilized within the present model needs to be refined. In this regard, several issues are discussed and suggestions for further simulation studies are put forward in order to account more precisely for the various features characterizing the defensive player's motor reaction in real sporting context.     

Distractor clustering enhances detection speed and accuracy during selective listening

The effects of distractor clustering on target detection were examined in two experiments in which subjects attended to binaural tone bursts of one frequency while ignoring distracting tones of two competing frequencies. The subjects pressed a button in response to occasional target tones of longer duration (Experiment 1) or increased loudness (Experiment 2). In evenly spaced conditions, attended and distractor frequencies differed by 6 and 12 semitones, respectively (e.g., 2096-Hz targets vs. 1482- and 1048-Hz distractors). In clustered conditions, distractor frequencies were grouped; attended tones differed from the distractors by 6 and 7 semitones, respectively (e.g., 2096-Hz targets vs. 1482- and 1400-Hz distractors). The tones were presented in randomized sequences at fixed or random stimulus onset asynchronies (SOAs). In both experiments, clustering of the unattended frequencies improved the detectability of targets and speeded target reaction times, Similar effects were found at fixed and variable SO As. Results from the analysis of stimulus sequence suggest that clustering improved performance primarily by reducing the interference caused by distractors that immediately preceded the target.