Impairment of nonverbal oral movements in aphasia

Thirty-six patients with unilateral cerebral vascular damage were required to perform a number of oral motor tasks, both verbal and nonverbal. Nonfluent aphasics were impaired in the imitation of single oral movements, as previously reported. However, on the imitation of complex nonverbal oral movements fluent aphasics were impaired as well as nonfluents. This impairment was not explicable on the basis of visual memory or perceptual deficits, nor on the basis of sensory thresholds as measured on the tongue. The findings suggest that deficits in coordinating oral movements are fundamental to most aphasic impairments, the meaningfulness of the responses not being a critical factor in the appearance of the defect.     

Right hemisphere appreciation of prosodic and linguistic indications of implicit attitude

Appreciation of attitudes conveyed through prosodic cues and lexical content was examined in subjects with temporal lobe seizure foci. One task involved auditory judgments of the consistency of verbal and intonational meaning of sentences. Errors on judgments of consistent verbal and prosodic stimuli were not only more frequent in the right temporal group than in left temporals or controls but were strongly related to neuropsychological indices associated with extent of right temporal involvement. Answering questions based on written narratives in which multiple attitude markers were either redundant or conflicting comprised the second task. Right temporal patients as a group had difficulty in answering inferential questions about paragraphs with inconsistent indicators of attitude. Even low-scoring right temporals were able, however, to answer inferential and factual questions when the verbal context markers consistently reinforced a particular attitude.     

Cerebral organization of oral and signed language responses: case study evidence from amytal and cortical stimulation studies

A normally hearing left-handed patient familiar with American Sign Language (ASL) was assessed under sodium amytal conditions and with left cortical stimulation in both oral speech and signed English. Lateralization was mixed but complementary in each language mode: the right hemisphere perfusion severely disrupted motoric aspects of both types of language expression, the left hemisphere perfusion specifically disrupted features of grammatical and semantic usage in each mode of expression. Both semantic and syntactic aspects of oral and signed responses were altered during left posterior temporal-parietal stimulation. Findings are discussed in terms of the neurological organization of ASL and linguistic organization in cases of early left hemisphere damage.     

The effect of reinforcement variables on inhibition in children with ADHD.

Behavioral inhibition, often cited as a central deficit in children with ADHD, has been shown to change in response to reinforcement. In this preliminary investigation, children with ADHD (n= 20) and matched controls (ages 7 to 12) completed a new version of the stop signal paradigm, the Fire Fighter Game, a measure of inhibition of a prepotent motor response, under three conditions: (1) no reinforcement; (2) immediate reinforcement; and (3) delayed reinforcement. In all conditions, the stop signal reaction time (SSRT) of children with ADHD was consistently longer than controls. Both groups improved significantly with reinforcement, and there was no strong evidence that immediate reinforcement was more effective than delayed reinforcement. However, it appeared that the reason for the changes in SSRT in response to reinforcement differed between the groups. Children in the control group responded faster on go trials, whereas children with ADHD improved their ability to inhibit responding with shorter stop delays. The relevance of these findings is discussed in terms of current theories of ADHD.     

Cortical localization of finger spelling and oral language: A case study

Finger spelling of letters and words was mapped by means of the cortical stimulation procedure in a hearing patient undergoing a left dominant anterior temporal lobe resection for relief of a seizure disorder. Finger spelling was disrupted at five sites: three overlapping with one or more oral language functions at sites in the classical posterior language area, two relating only to finger spelling in the anterior temporal region. Following the resection which included these latter sites, both short- and long-term postoperative deficits in finger spelling are described. Implications for the organization of manually based communication behavior in the left hemisphere are discussed.     

Impairments of nonverbal oral movements after left hemisphere damage: A followup analysis of errors

Acquisition of a task requiring the imitation of a series of nonverbal oral movements is most severely impaired in patients with aphasic disturbance. However, nonaphasic patients with left hemisphere damage also perform more poorly than patients with right hemisphere damage or normal control subjects. Analysis of the errors made on the multiple oral movements task reveals that left, but not right, hemisphere damage is highly associated with perseverative responses. Patients with right hemisphere damage do not differ significantly from normal control subjects in the acquisition of or in the type of errors made on the task. It is suggested that the left hemisphere plays an important role in the control of nonverbal oral movement production.     

Developmental impact of frontal lobe injury in middle childhood.

Executive function of frontal lobe systems, like intelligent behavior, appears to demonstrate two major features: it is adaptive and goal-directed. Disruption of executive function following injury to the frontal lobes in childhood might be predicted to impact the trajectory of normal cognitive, behavioral, and social development. Case studies of two children injured at different ages showed the primary developmental impact to involve the behavioral and social realms. While cognitive development may be suspected to also be considerably influenced, assessment of changes in cognitive abilities by traditional psychometric means was found to be problematic. Psychometric changes were found to occur over a prolonged period of time, emphasizing the importance of documenting observations and chronicling postinjury events.     

A Review of the Stereotype Threat Literature and Its Application in a Neurological Population

Stereotype threat is a situational phenomenon, leading to test performance decrements, in which a member of a stigmatized group feels pressured by the possibility of confirming or being judged by a negative stereotype. This review article highlights the progression of research in the stereotype threat field, and its relevance to neurological populations. Early studies focused on demonstrating this effect in African American, women, and elderly populations. Since this time, research has continued to focus on these populations but has moved to elucidating stereotype threat's mediating psychological factors, studying the impact of individual differences in response to stereotype threat, and attempting to reduce its overall effect. A proposal for further study in neurological populations, under the framework of stereotype threat, comprises the last portion of the paper. It is argued that this social psychological phenomenon may, at least in part, account for poor neuropsychological test performance for neurologically compromised individuals.