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.     

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.     

Additive latency effects of selective and nonselective restricted priming types

The purpose of this investigation was to examine further the contention of Alain et al. (1988) that a third priming type exists, called nonselective restricted (NSR) and controlled by response probability, which is distinct from those types influenced by foreperiod duration (nonselective general priming) and prediction probability (selective priming). In a four-choice reaction time (RT) task, prediction probability (.5, .7, & .9, indicating the likelihood of a particular response) and response probability (.5, .9, denoting the likelihood that a response would be needed at all) exerted significant but noninteractive effects on RTs for prepared responses (most probable), suggesting that each of these probabilities influence different priming types (Sternberg, 1969; selective and NSR, respectively). This was further indicated by the fact that prediction probability, but not response probability, significantly altered RTs for the unprepared (lesser probable) responses. Finally, the hypothesized nonselective character of NSR priming (i.e., all outputs controlled by response probability are equally affected by its value changes) was supported when responses were equiprobable, and, while the null effect of response probability just mentioned seemingly argued against this property when selective priming took place, the interpretation provided herein negated this opposition.     

Deconstructing the declaration: A case study in pragrammatology

I would like to thank Jonathan Lee, Terry Pinkard, Steven S. Schwarzschild, Jill Petzall, Bob Gibbs, Bill Hamrick and Jim Bohman for their very helpful criticisms of earlier drafts of this paper.     

Updating an object’s orientation and location during nonvisual navigation: A comparison between two processing modes

In the present study, we compared the effects of two processing modes on the updating of the location and orientation of a previously viewed object in space during a guided walk without vision. In Experiment 1, in order to measure the error for initial perception of object’s orientation, 12 subjects rotated a miniature model until it matched the memorized orientation of its counterpart object in space. In Experiment 2, they attempted either to keep track of the object continuously (in the object-centered [OC] task) or to estimate the object’s perspective only at the terminal vantage point given the trajectory they walked (in the trajectory-centered [TC] task). Subjects indicated the location of the object by facing it, and then rotated the model in order to indicate its orientation from the new vantage point. Results showed that, with respect to the TC mode, the OC mode induced a slowdown of the subjects’ self-paced locomotion velocity for both linear and angular movements, and a decrease of the latencies as well as smaller absolute errors for the orientation-of-the-object response. Mean signed errors on object’s orientation were equivalent for both processing modes, suggesting that the latter induced different allocations of processing resources on a common representation of space updated by “path integration.”