Hemispheric differences in semantic processing: Category matching is not the same as category membership

Two closely related semantic processing tasks were studied under identical procedural conditions in order to examine lateral visual field effects on reaction times. In Experiment 1, reaction times did not differ as a function of visual field when subjects decided whether a lateral word was a member of a foveally presented category word (category membership task). On the other hand, reaction times were faster for right than for left visual field stimulus presentations when subjects decided whether two words, one lateral and one foveal, belonged to the same category (category matching task), although this advantage did not occur immediately. In Experiment 2, the laterality effect in the category matching task was studied as a function of word familiarity. Two groups of subjects performed the matching task for two blocks of trials, one group receiving the same word list in each block and the other receiving different lists. No visual field differences in reaction times were observed for either group during the first block of trials, but a distinct right field advantage appeared for both during the second block. The data from these experiments suggest that category matching strategies rely upon structures or processes localized in the left hemisphere, although their influence is not immediate. Category membership strategies, on the other hand, do not depend upon such localized structures.     

An investigation of computer-assisted cognitive-behavior therapy in the treatment of depression

Increasing demands are being placed on a limited pool of mental health professionals to deliver a steadily growing array of effective treatments in an efficient and acceptable manner. The integration of behavioral technology and computing technology may provide a possible solution to the problem of resource limitations. An interactive computer-assisted program for the treatment of mild to moderate unipolar and dysthymic depressive disorders is described. The effectiveness of this treatment will be empirically examined.     

Material-specific perceptual interference for visual words and faces: implications for models of capacity limitations, attention, and laterality

Four experiments were conducted to test the hypothesis that perceptual interference effects would be greatest among items that are processed by the same hemisphere than among items processed by different hemispheres. Recognition of two peripheral faces, flanked on either side of a central item that also had to be identified, was worse when the item was a face than when the item was a word. The opposite results were obtained for peripheral word identification by naming (Experiment 1). Identical results were obtained when a nonsense form was substituted for the central face (Experiment 2). Since unfamiliar faces and nonsense forms are processed primarily by the right hemisphere and words are processed by the left, the results are consistent with the hypothesis. The interference effect was the same even when the central nonsense shape was identified by naming, suggesting that the locus of the effect is not at response selection (Experiment 3). Ignoring the central item only reduces the interference effects but does not eliminate it (Experiment 4). Although in general words were perceived better in the right visual field, and faces were perceived better in the left, small fluctuations in the magnitude but not in the direction of perceptual asymmetries were sometimes noted with changes in the central item. The fluctuations were usually opposite to those predicted by attentional models of perceptual asymmetries.     

Therapeutic approaches to families of young Israeli soldiers

This paper presents a set of family interventions performed in a civilian psychiatric unit with patients who were young Israeli soldiers. The work was done with a psychoanalytic orientation coupled with special attention to the general cultural characteristics of the surrounding society as well as to the particular ones of the families themselves. An experience of group therapy with the soldiers' parents will also be described in detail.     

Real knowledge

Philosophers have sought to characterize a type of knowledge — what I call real knowledge — which is significantly different from the ordinary concept of knowledge. The concept of knowledge as true, justified belief — what I call knowledge simpliciter — failed to depict the sought after real knowledge because the necessary and jointly sufficient conditions of knowledge simpliciter can be felicitously but accidentally fulfilled. Real knowledge is knowledge simpliciter plus a set of requirements which guarantee that the truth, belief and justification conditions are not accidentally conjoined. Two of those requirements have received considerable attention in recent literature by the defeasibility theorists and the causal theorists. I argue that a third requirement is needed to block the merely coincidental cosatisfaction of the belief and justification conditions and to capture our intuitions about the epistemic agent who possesses real knowledge. That condition ascribes a disposition to the real knower to believe all and only justified propositions in virtue of his/her belief that the propositions are justified. Two consequences of that requirement are discussed: (1) if S really knows that p, then S knows simpliciter that S knows simpliciter that p and (2) the iterative feature of real knowledge mentioned in (1) provides a basis for the rejection of a particularly pernicious form of scepticism.     

Against a role for attentional disengagement in the gap effect: A friendly amendment to Tam and Stelmach (1993)

Saccadic reaction time (RT) is reduced when the fixation point is removed shortly before target onset. Although Tam and Stelmach (1993) argued that thisgap effect could not be explained solely by the idea that fixation offset disengaged visual attention and preferred an explanation based on disengagement of the oculomotor system, they felt that they could not rule out a hybrid model in which both oculomotorand attentional disengagement contribute to the gap effect. Our analysis of the dual response experiment (Experiment 4), upon which this hybrid model was based, shows that manual and saccadic responses were likely compromised by a grouping or delay strategy and that subjects may not have been attending as instructed. On these grounds, we argue that Tam and Stelmach (1993), like Kingstone and Klein (1990; 1993a) provide no evidence that attentional disengagement contributes to the gap effect. An alternative proposal (Klein & Kingstone, 1993), that motor preparation and oculomotor disengagement combine additively to produce the gap effect, is consistent with the data from Tam and Stelmach’s Experiments 1–3, is similar to the explanation that they prefer, and has been strongly supported when directly tested (Kingstone, Klein, & Taylor, 1994).     

The evidence for a temporal processing deficit linked to dyslexia: A review

The existence of a phonemic deficit that is predictive of, and probably causal to, many cases of reading difficulty is well established. Tallal (1984) has suggested that this phonemic deficit is in fact a symptom of an underlying auditory temporal processing deficit. Our purpose in this paper is to evaluate the plausibility of this hypothesis. The various components that might constitute sequential (or temporal) processing are described. Our review of the literature reveals considerable evidence for a deficit in dyslexics in stimulus individuation tasks (e.g., gap detection) and temporal order judgments in both the auditory and visual modalities. The possibility that a general temporal processing deficit is associated with dyslexia, as suggested by Tallal (1984), is explored, and possible etiologies for such a deficit are discussed. The possibility of a causal link between temporal processing deficits and some reading disabilities is demonstrated, and converging evidence from morphological studies is reviewed. It is concluded that a temporal processing deficit does appear to be present in many developmental dyslexics, and strategies are suggested for further research aimed at evaluating the hypothesis that this deficit may be the root cause of a number of cases of dyslexia itself.