The case against mental duality

The arguments for and against Puccetti’s (1981a) notion of “mental duality” are reviewed. This model of mind asserts that not only do commissurotomy patients have two independent spheres of consciousness but so do normal intact brains. The role of the corpus callosum is viewed as being purely duplicative, not integrative. Following a detailed discussion of conceptual and terminological issues, neuropsychological and neuroanatomical considerations, and various clinical implications of the model, it is concluded that the available empirical evidence refutes the model and that the model is conceptually inadequate.     

The case against mental duality

The arguments for and against Puccetti’s (1981a) notion of “mental duality” are reviewed. This model of mind asserts that not only do commissurotomy patients have two independent spheres of consciousness but so do normal intact brains. The role of the corpus callosum is viewed as being purely duplicative, not integrative. Following a detailed discussion of conceptual and terminological issues, neuropsychological and neuroanatomical considerations, and various clinical implications of the model, it is concluded that the available empirical evidence refutes the model and that the model is conceptually inadequate.     

Hypnotic susceptibility and verbal automaticity: automatic and strategic processing differences in the Stroop color-naming task.

The original hypothesis of Dixon, Brunet, and Laurence (1990) that highly hypnotizable (HH) subjects process words more automatically than do low hypnotizable (LH) subjects was retested in a paradigm that separated strategic from automatic processes in the Stroop color-naming task. The words red and blue preceded a color patch that was red or blue. Subjects were told that the word predicted the opposite color 75% of the time. Automatic and strategic processes were assessed by varying the interstimulus interval (ISI) between the word and the color patch. Both HH and LH subjects showed significant strategic effects (faster incongruent-trial, color-naming reaction times than congruent-trial reaction times at ISIs over 400 ms), but only HH subjects showed significant automaticity (significantly faster congruent-trial reaction times than incongruent-trial reaction times at 16.7 ms, the lowest ISI).     

Relation between food preference and food-elicited vocalizations in golden lion tamarins (Leontopithecus rosalia).

We report the results of 2 studies on food-elicited vocalizations in golden lion tamarins (Leontopithecus rosalia). First, we investigated the preferences of 10 golden lion tamarins for 6 foods. Tamarins prefer mealworms and raisins significantly more than apple, egg, carrot, or marmoset diet. Food preference rank was significantly and positively correlated with the rank of latency to choose a particular food. Second, we investigated the relation between food preference and 15 vocal parameters measured from the calls emitted by 5 tamarins to a subset of the foods. Only 1 parameter was significantly correlated with food preference across animals. Within-subjects multivariate analysis of variance showed that the vocalizations to foods are significantly different. Our results support an hypothesis that food-elicited vocalizations vary in ways that correspond to the caller's preference but not in a manner that labels food type.     

Bioethics in the twenty-first century: why we should pay attention to eighteenth-century medical ethics.

Those of us who work in the field of bioethics tend to think that, because the word "bioethics" is new, so too the field is new in all respects, but we are not the first to do bioethics. John Gregory (1724-1773) did bioethics just as we do it, at least two centuries before we thought to do it. He deployed philosophical methods as sophisticated as our own. Indeed, Gregory took up the very best moral philosophy available to thinkers of the Scottish Enlightenment, namely, David Hume's moral philosophy and its core concept of sympathy. Gregory also responded in a conceptually powerful and clinically applicable way to the problems of his time, just as we do. I want here to outline Gregory's accomplishment and to identify some aspects of its importance for bioethics in the twenty-first century.     

Attributions for dietary failures: problems reported by participants in the Hypertension Prevention Trial

Assigned participants in the Hypertension Prevention Trial to one of four diets for a period of 3 years: (a) weight loss, (b) reduced sodium, (c) weight loss plus reduced sodium, and (d) reduced sodium plus increased potassium. At 6-month intervals, they reported problems they were having adhering to their diets. Problem attributions were coded along the dimensions of internality, stability, and controllability and were categorized as intrapersonal or extrapersonal. Attributions were found to differ by type of diet and sex of participant. Participants assigned to weight-loss groups were significantly more likely than those assigned to non-weight-loss groups to blame themselves for their problems with adherence, making characterological as opposed to external or situational attributions. Men perceived problems to be more controllable than women. Attributions did not predict weight loss, change in urinary sodium, or change in potassium excretion.