The other side of the coin: Cognitive properties of nonreward

In this comment, I examine Amsel’s theory in the light of rats’ reaction not to frustrative non-reward per se, but to the more complicated case in which frustrative nonreward is part of a rule-based sequence of reward quantities. The discussion goes beyond Amsel’s emphasis on dispositional memory to consider cognitive and representational memory—the signaling properties of reinforcement and nonreinforcement. The strengths and weaknesses of Amsel’s theory are discussed with the fresh perspective that this viewpoint provides, and some issues emerge that may be fruitful for further study.     

Psychosocial knowledge and allopathic medicine: Points of convergence and departure

The past 15 years have witnessed a call for allopathic medicine to incorporate psychosocial perspectives into education and clinical practice. While a biopsychosocial perspective has influenced academic medicine in areas such as primary care and psychiatry, its direct impact on clinical medicine has been questionable. One barrier to the incorporation of psychosocial information into medicine which has only recently received attention has been different cultural assumptions which govern medicine versus the social-behavioral sciences. These assumptions are examined in the context of four issues: knowledge paradigms, models of education, acculturation of psychosocial knowledge into medicine, and patient autonomy. This cultural analysis provides a vantage point for understanding similarities as well as points of divergence between psychosocial and biomedical knowledge and practice.     

Monitoring running-wheel movement using a serial mouse and an IBM-compatible system

A running-wheel-movement-detection system is described for use with an IBM-compatible system and a serial mouse. It is an adaptation of a system developed for use on a Commodore 64. The IBM-compatible system provides obvious advantages in speed, memory, data storage, and programming ease over the earlier Commodore 64 system.     

Cognitive function after open-heart surgery: Are postoperative neuropsychological deficits caused by cardiopulmonary bypass?

Despite the many technological developments in arterial perfusion and cardiac surgical procedures, open-heart surgery is still believed to pose a significant risk for cerebral injury. There are several potential causes of brain damage during open-heart surgery, including prolonged or severe arterial hypotension, as well as emboli emanating from the cardiopulmonary bypass circuit or the operative field. This article reviews the available neuropsychological studies of outcome following cardiac valve replacement and coronary artery bypass grafting. Because both procedures are life-saving operations, the research in this area has been quasi-experimental and fraught with methodological problems. Nonetheless, the findings converge to suggest that cognitive dysfunction occurs after open-heart surgery, and that the deficits are attributable, at least in part, to factors specific to the operation or to the patient being maintained on cardiopulmonary bypass. Preliminary findings suggest that embolization is the primary cause of perioperative deficits in uncomplicated operations. Studies have also consistently found preoperative deficits in this population, suggesting that neuropsychological dysfunction is caused by severe chronic cardiac disease as well as open-heart surgery.