Aphasia type and aging in Hindi-speaking stroke patients

In this study, the clinical profile of Hindi-speaking stroke patients with aphasia from northern India has been investigated. We examined the interactional effect between age and gender with aphasia type in 97 Hindi-speaking right-handed individuals, the majority of them with a confirmed diagnosis of a cerebrovascular accident. The subjects included in the study ranged from 3 weeks to two years post-onset with a diagnosis of a common classical aphasia (Broca's, Wernicke's, anomic, global, conduction, and transcortical) types involving both males and females. Also examined was the interaction between literacy and aphasia type since the subjects had varied exposures to education (total illiteracy to professional/university education). While the data reported here about Hindi-speaking aphasics are relatively in agreement with the age-aphasia type patterns discussed in western countries, nonetheless some differences were also observed. The mean age of Indian patients with aphasia was significantly lower. Also, in addition to some gender and literacy related differences, an outstanding difference was that many clinical symptoms that are known to co-occur with aphasia were not readily reported by subjects with stroke.     

A Comparison of Homeless Male Veterans in Metropolitan and Micropolitan Areas in Nebraska: A Methodological Caveat

This study explored differences between homeless male veterans in metropolitan and micropolitan cities in Nebraska on sociodemographic, housing, clinical, and psychosocial characteristics as well as health service use. A convenience sample of 151 homeless male veterans (112 metropolitan, 39 micropolitan) were recruited from Veterans Affairs facilities and area shelters in Omaha, Lincoln, Grand Island, and Hastings in Nebraska. Research staff conducted structured interviews with homeless veterans. Results showed that compared to homeless veterans in metropolitans, those in micropolitans were more likely to be White, unmarried, living in transitional settings, and were far more transient but reported greater social support and housing satisfaction. Veterans in micropolitans also reported more medical problems, diagnoses of anxiety and personality disorders, and unexpectedly, were more likely to report using various health services and less travel time for services. Together, these findings suggest access to homeless and health services for veterans in micropolitan areas may be facilitated through Veterans Affairs facilities and community providers that work in close proximity to one another. Many homeless veterans in these areas are transient, making them a difficult population to study and serve. Innovative ways to provide outreach to homeless veterans in micropolitan and more rural areas are needed.     

Stuttering acquired from subcortical pathologies and its alleviation from thalamic perturbation

Acquired stuttering subsequent to subcortical pathology of mesothalamus was observed in four neurosurgical subjects. The patients suffered from chronic pain, seizures, and somatosensory disorders. They also exhibited unpredictable and uncontrollable speech, spasmodic blocks which were devoid of accessory features, and adaptation effect. Therapeutic mesothalamic stimulation, used as a treatment of last resort to relieve the pain and associated symptoms, also had an ameliorating effect on the stuttering. Spontaneously occurring focal abnormal EEG discharges were anatomically delineated and used as a guide for therapeutic stimulation electrode placement. Attentuation of the abnormal discharges was followed by alleviation of symptoms. This investigation examines the clinical characteristics of stuttering in four neurosurgical patients and suggests an electropathologic basis for their mesothalamic-generated speech dysfluencies. The cooccurrence of pain, seizures, somatosensory disorders, and stuttering, and their concurrent amelioration, suggests that both chronic pain and stuttering may be implicated by similar or related reticular electropathologic generators, couched in overlapping reticular networks extending from the brain stem to the thalamus, and that the acquired stuttering may be recruited as one component of a larger syndrome complex.     

Some errors of perceptual analysis in visual search can be detected and corrected

This experiment tried to discover whether people can correct errors which occur because they incorrectly analyse a display to which they have to respond--whether, in fact, they can correct “perceptual” as well as “motor” errors. In a serial, self-paced visual search task, subjects made one response to indicate that a display of five or nine letters contained either of a pair of target letters, and another response when no target was present. Omission errors were much more common than False Identification Errors, but more of them were corrected. Omission errors were detected and corrected faster than False Identification Errors. Typically omission errors were slow responses while False Identification Errors were fast responses. It is possible to deduce that at least some errors resulting from incorrect analysis of a display can be detected and corrected, probably because of an extension of perceptual analysis during, or immediately after, the time when a response to the display is made.     

Improvement, learning and retention of skill at visual search

Three experiments examined factors responsible for improvement in visual search. In Experiment I three groups of subjects were each trained for 3000 trials to search for a particular set of target letters among a particular set of background letters. After intervals of 2, 4, or 6 weeks without further practice they were re-tested, either with the same displays or on new displays which they searched for the same target items among new background items. Negative transfer suggested that memory for specific cue-systems distinguishing target from background letters is retained for as long as 4 weeks.

Experiment II examined performance of three very highly practised subjects. After 25 days practice, variations in the size of the target set no longer affected search time. This could not be explained by learning of specific cue systems, since after this amount of practice subjects showed perfect transfer to displays which they searched for the same target items among new background items. Experiment III suggested that practised subjects achieve this high level of competence by learning to make two independent successive decisions, first to locate any member of the target set on the display and next to identify which particular member of the target set has been located.     

Effects of intralaminar thalamic stimulation on language functions

Fifteen neurosurgical subjects, who were undergoing thalamic chronic electrode implants as a treatment for dyskinesia and chronic pain, were evaluated on a series of neurolinguistic functions to determine if the stimulation of the centromedianum nucleus of the thalamus affected language and cognitive processing. Analysis of the data revealed that the stimulation of the left centromedianum nucleus had resulted in a notable facilitatory influence on the processing of language functions; this facilitatory effect was measured in terms of the number of errors produced and the patients' response latency time. The facilitatory effect was also noted to have extended to other language functions. The nature of the facilitation from the stimulation of the left centromedianum nucleus, an extension of the brainstem reticular formation, on language functions is discussed.     

Tonotypic cortical representation in man (case report)

Cortical stimulation—evoked perception of tones differing in pitch suggests that the perception of pitch may be discretely organized in the human auditory parakoniocortex. Findings, obtained from a neurosurgical patient undergoing temporal lobectomy, are discussed with reference to anatomical and functional considerations of the auditory parakoniocortex in humans. These tonotypic findings are potentially significant since, as previously reported (see references in Discussion section), auditory sensations have not been analyzed in relation to perceptual categories of pitch. Address correspondence to: Department of Speech Pathology and Audiology, Marquette University, Milwaukee, Wisconsin 53233.     

Behavioral analysis of NR2C knockout mouse reveals deficit in acquisition of conditioned fear and working memory

N-methyl-D-aspartate (NMDA) receptors play an important role in excitatory neurotransmission and mediate synaptic plasticity associated with learning and memory. NMDA receptors are composed of two NR1 and two NR2 subunits and the identity of the NR2 subunit confers unique electrophysiologic and pharmacologic properties to the receptor. The precise role of NR2C-containing receptors in vivo is poorly understood. We have performed a battery of behavioral tests on NR2C knockout/nβ-galactosidase knock-in mice and found no difference in spontaneous activity, basal anxiety, forced-swim immobility, novel object recognition, pain sensitivity and reference memory in comparison to wildtype counterparts. However, NR2C knockout mice were found to exhibit deficits in fear acquisition and working memory compared to wildtype mice. Deficit in fear acquisition correlated with lack of fear conditioning-induced plasticity at the thalamo-amygdala synapse. These findings suggest a unique role of NR2C-containing receptors in associative and executive learning representing a novel therapeutic target for deficits in cognition.     

A multicriteria assignment problem

Our objective in this paper is to propose a procedure for solving a multicriteria assignment problem. Given qualitative and quantitative data, the proposed procedure makes assignments taking into consideration the multicriteria aspect of the problem. As an illustrative example, we consider the assignment of referees to the football matches in an Italian championship. Copyright © 2003 John Wiley & Sons, Ltd.     

A four-country investigation of factors facilitating student internet use.

Education and national culture may influence Internet use. The present study explored factors that might facilitate college students' use of the Internet across samples in four countries: India, Mauritius, Reunion Island (an overseas Department of France), and the United States. Questionnaire data was collected on students' extent and frequency of Internet use. Also, structured items asked about the factors that would help them to use the Internet more. Data was analyzed using dummy-coded multiple regression so as to compare responses across the country groups. The U.S. sample was coded as the reference group so that the regression coefficients in the equation provided a comparison between the U.S. sample and each other country represented. Further country comparisons were made using t-tests for differences between the regression coefficients. Results suggested that there was more Internet use in the U.S. sample compared to the others. The Non-Western samples also reported greater desire for Internet access and non-English web sites. Training on how to use the Internet and course requirements for Internet use were reported as helpful by the India and Mauritius groups to a greater extent than by those in Reunion and the United States. Implications of the present exploratory results are discussed for applications of theoretical models across cultures.