Event-related potentials in phonological matching tasks

Two experiments investigated Event-Related Potentials (ERPs) in matching tasks. In Experiment 1 subjects judged, in separate conditions, whether two words rhymed or were written in the same case. The CNV developing between the two words was larger in the latter task compared to the former at the right temporal site. In the rhyme judgment task, an increased late negativity differentiated the ERPs to nonrhyming words from those that rhymed with the previously presented word. This difference was maximal at the midline and over the right hemisphere. Experiment 2 further investigated ERPs in the rhyme judgment task, increasing memory demands with an extended interstimulus interval (ISI) and varying the number of items subjects had to hold in memory during this period (one vs. three). Irrespective of memory load, CNVs during the ISI were more negative from the left hemisphere, and the ERPs to the rhyming and nonrhyming words showed the same differences as in Experiment 1. The CNV asymmetries are interpreted as being associated with the engagement of lateralized short-term memory processes. The rhyme/nonrhyme differences are possibly related to the “N400” component elicited by semantically incongruous words. Possible reasons for their scalp distribution are discussed.     

Recovery of single word comprehension: CT-scan correlates

9tory comprehension for single words, as measured by the BDAE Word Discrimination subtest, was studied longitudinally in a group of 37 aphasic patients. The majority of the patients had impaired performance at 1 month postonset, but recovery by Month 6 postonset was quite striking. Damage to Wernicke's area did not preclude recovery of single word comprehension to within the normal range. Only patients with very extensive left hemisphere lesions had incomplete recovery of single word comprehension.     

Effects of subgrouping in stuttering research

The most frequently utilized research design in stuttering research compares stutterers to nonstutterers, with the assumption that stutterers represent a homogeneous group. The present study examines the effects of subgrouping stuttering subjects. Sample populations were randomly selected from a pool of stuttering children, successively increasing the stringency of selection criteria for group membership. The groups were contrasted across five dependent variables. The results indicated that the performance differences between the groups increased as the selection criteria became more stringent. The findings were interpreted as supporting the need to more closely examine the individual differences of stutterers, deviating from the traditional research paradigm.     

Economic deprivation and the quality of parent-child relations: A trickle-down framework

The trickle-down model of economic activity proposes that changes in economic activity permeate downwards from incentives or disincentives to business, which affect business income, investment, employment, and the absolute and relative economic deprivation of the poor. Within an extended trickle-down framework, this paper examines how these effects trickle further downwards to influence the quality of parent-child relations. Two cases are examined. First, deprivation is discussed as it trickles down to affect the parental image conveyed to children, and in turn perceptions od parents are examined as these predict children's problem behavior. Second, deprivation is discussed as it trickles down to affect parents' psychological well-being and child-rearing capabilities, particularly as manifested by the incidence of child abuse and neglect. The evidence to date converges to indicate that children in general are not necessarily aware of or sympathetic to the plight of those under economic strain. Economic deprivation may exacerbate conflict in the family, diminish children's perceptions of parents, and give rise to problem behavior in boys. Evidence also suggests that deprivation may be an antecedent of poor psychological well-being in adults and child abuse. Possibilities for a “bubble up” model of economic activity are explored together with directions for further research.     

Lateral preferences and writing hand posture in left-handers: A reply to Levy

In reply to the commentary from J. Levy about a recent article of ours (A. Searleman, C. Porac, & S. Coren, 1984, Brain and Cognition, 3, 86–93), we find that she has shifted the level of analysis from between-sex comparisons (as demanded by our original hypothesis) to within-sex comparisons. Since she is addressing a different set of questions, we therefore find no compelling reasons to alter any of our conclusions or the confidence that we have in these conclusions.     

Tactile spatial ability: Lateralized performance of deaf and hearing age groups

Hearing adults, 8- and 6-year-old children, together with deaf 9-year-old children, were tested on a unimodal haptic matching task. One additional group of adults was tested with a shorter stimulus presentation time. Data indicated that left-hand superiority was most evident in the performances of the older hearing children, and of the adults with the shorter presentation time. Hemispheric specialization was less noticeable for the younger hearing group, but the task may have been too difficult. A slight right-hand superiority was found in the performance of adults with long presentation time. This may reflect the simplicity of the task for these subjects. Deaf children did not show any clear hand differences, but were superior in overall performance to hearing children.     

Language skills in developmentally disabled children

Language measures of receptive and expressive vocabulary, story telling, and immediate verbal memory, as well as two perceptual tests, were administered to a group of developmentally disabled children, and three groups of normal children, one matched for chronological age, one for mean length of utterance, and one for performance on one of the perceptual tests. When diagnostic subgroups of “autism,” “childhood schizophrenia,” and “other severe disturbance” were formed using standard diagnostic tools, no language differences were found between diagnostic subgroups. When compared with the normal control groups, many of the language skills of the entire group of disabled children, and of the autistic children alone, were rather evenly delayed, showing only a relative sparing of the naming function, and a relative deficit on immediate verbal memory. Furthermore, a high correlation was found in a small subsample between the difficulty levels of morphemes in the disabled children and those reported for young normal children. Experienced special-education and early-childhood teachers could not discriminate the stories of the disabled children from those of young normal children. Analysis of the disabled children's error strategies, however, revealed features of their language not found in normal children's language: (1) extreme perseveration in test answers and stories, (2) attention to minor features of test stimuli, and (3) failure to adopt alternate, flexible communicative strategies. We conclude that the language acquisition of the developmentally disabled children is delayed but not deviant in its semantic and syntactic competence, and that current diagnostic practice does not differentiate linguistically distinct subgroups. We further argue that where developmentally disabled children do exhibit aberrant features of language, such deviance parallels similar features in other cognitive skills, and is not unique to language.     

Risky decision: Attention and path dependency as a function of response mode

It was previously shown and was here replicated that the amount of money required to induce a subject to exchange one gamble for a second and then the second for a third depends on the second (intermediate) gamble. This path dependency cannot be explained by any of the algebraic models (including SEU), nor can it be explained as a simple attention effect. A model was put forward which explains the effect in terms of differential masking depending on a kind of stimulus—response compatibility. The effect of response mode on path dependency was examined in this study; similarity judgements showed no consistent path dependency nor did difference in rated attractiveness of gambles presented in pairs, but rated attractiveness was different for gambles presented singly. Since it might be that monetary response emphasises the monetary aspects, that is, the winning amount of the gamble, it was thought that a probability response would emphasise the probability of winning. However, when subjects were asked to set the probability of winning $ 12 which would induce them to exchange one gamble for another, not only was no path dependency observed, but the subjects' responses seemed to depend only on the difference in expected value of the gambles. This suggests the possibility of developing response-display modes which would eliminate or at least attenuate the inconsistencies observed in risky decision processes.     

Risky decision: Attention effects or masking effects?

The Marshak bid procedure shows that more money is required to induce a S to exchange gamble a for gamble e and then e for b if e differs from a only in the winning amount and differs from b only in the probability of winning, rather than if e differs from a only in the probability of winning. This is contrary to most theories of risky decision making which imply that the amount of money necessary to effect a 2-step exchange between a and b should be independent of the intermediary gamble. One might attempt to explain the effect by saying that the S attends to the dimension which is different between gambles. But the explanation is untenable if one assumes that states of attention are defined as weightings of the dimensions. An alternative explanation is put forward which basically assumes that winning amounts mask differences in probability of winning more than vice versa. The formalization of the theory is given in terms of Fechnerian integration over imperfect differentials.