PubMed Health⌕ Search

Biomedical subjects

M Seidenberg

Publications and source records attributed to M Seidenberg.

At least 55 records · Page 3Linked to original sources
PubMed1992

Childhood epilepsy and the role of psychology.

The relatively long history of psychology's involvement in the field of epilepsy is discussed. The view of epilepsy is that of a chronic disorder with onset in childhood, at a time when normal development is at risk for interference from the direct and secondary aspects of repetitive seizures, the neurological abnormalities from which they arise, and the clinical interventions that attempt to control them. The objective and scientifically based methods of psychology are viewed as particularly well suited to these topics. Past efforts by psychologists have increased understanding of the syndrome that is epilepsy, and have paved the way for opportunities to further contribute to the theoretically and practically important problems associated with epilepsy.

Adaptation, Psychological↗
PubMed1992

Two allosteric modulators interact at a common site on cardiac muscarinic receptors.

The abilities of gallamine, obidoxime, tetrahydroaminoacridine (THA), and 8-(N,N-diethylamino)octyl-3,4,5-trimethoxybenzoate (TMB-8) to alter the rate of dissociation of N-[3H]methylscopolamine from rat cardiac muscarinic receptors were investigated. All four ligands monotonically slowed the dissociation, with the order of potency gallamine > TMB-8 > THA > obidoxime. There was a dramatic difference in the efficacy of these allosteric modulators. Gallamine, TMB-8, and THA slowed the dissociation of N-methylscopolamine by > 90% at maximally effective concentrations, whereas obidoxime was capable of slowing it by only about 50%. In a manner analogous to the action of a partial agonist, obidoxime was able to partially reverse the effects of the other three modulators. Furthermore, the concentration-dependent effects of combinations of obidoxime and gallamine were in good agreement with the model of competitive interaction between these two ligands. These results provide the first evidence that two muscarinic allosteric modulators interact competitively at a well defined site.

Allosteric Regulation↗
PubMed1991

Mood state in unilateral temporal lobe epilepsy.

The purpose of this investigation was to reexamine the relationship between self-reported depression and laterality of temporal lobe epilepsy and to determine the contribution of associated frontal lobe dysfunction in predisposing patients to depression. Sixty-four patients with complex partial seizures of left (n = 26) or right (n = 38) temporal lobe origin were administered several self-report measures of mood state (Beck Depression Inventory, Center for Epidemiological Studies-Depression scale, Beck Anxiety Inventory), and a test of frontal lobe function [Wisconsin Card Sorting Test (WCST)]. There were no overall differences between the left and right temporal lobe groups on the measures of depression and anxiety. However, the left temporal lobe group exhibited a significant relationship between the degree of associated frontal lobe dysfunction (as indicated by increased perseverative responding on the WCST) and dysphoric mood state. For the right temporal lobe group there was a nonsignificant inverse relationship between mood state and indices of frontal lobe dysfunction. These results (1) are consistent with the broader psychiatric literature, which has implicated a relationship between depression and left frontal lobe dysfunction, (2) suggest that previous conflicting reports of depression/left temporal lobe epilepsy relationships are due in part to variations in the intactness of frontal lobe function, and (3) suggest that the presence of associated frontal lobe dysfunction may be a consideration in understanding interictal psychopathology in epilepsy.

Adult↗
PubMed1989

Priming and semantic memory loss in Alzheimer's disease.

Semantic memory (SM) was investigated in six patients with probable Alzheimer's disease (AD) by on-line measurement of semantic priming in a lexical decision task, and off-line tests of comprehension. Detailed assessment was carried out on naming, name comprehension, and probes of semantic knowledge with a battery of 150 items. The patients performed normally on perceptual tests and displayed an item-specific loss of knowledge on the semantic tests. In a primed lexical decision task, greater semantic priming was found relative to age-matched normals. The priming was substantially greater for items with "degraded" representations as determined by the off-line tests. Lexical decision was also performed more slowly on these items. These unexpected results demand a reevaluation of the concepts of the lexicon and semantic memory structure and their possible alteration in dementia.

Aged↗
PubMed1989

Changes in cerebral functioning associated with normal aging.

It has been suggested that the normal aging process is characterized by a pattern of neuropsychological performance decline that implies relatively greater vulnerability of right-hemisphere functions. This hypothesis was tested in a sample of 68 volunteers aged 20-75 who were free of systemic and neurologic illness. Neuropsychologic measures of lateralized and focal function were specifically selected to eliminate systematic procedural differences among tests (e.g., timed vs. untimed, overlearned vs. unfamiliar). Inferences about the localizing significance of each measure were based on previously demonstrated double dissociation of function in lesion studies. Results suggested that declines in cerebral efficiency are not differentially lateralized. Age correlated performance changes implied bilateral reduction that was significantly more pronounced on operations associated with frontal-lobe function. Anatomic and theoretical explanations for this pattern were discussed.

Adult↗
PubMed1989

Gallamine exerts biphasic allosteric effects at muscarinic receptors.

Although gallamine and a number of other compounds have been reported to slow the rate of dissociation of labeled ligands, especially [3H]N-methylscopolamine (NMS), from muscarinic receptors of heart and brain, there has been some dispute as to whether the dissociation of [3H]quinuclidinyl benzilate (QNB) is subject to such allosteric regulation. The present studies were intended to determine whether past discrepancies might be due to differences between tissues. We have found that gallamine modulates the dissociation of [3H]QNB from muscarinic receptors of the heart in a biphasic manner. Low concentrations (micromolar) accelerate the rate of dissociation, whereas higher concentrations (millimolar) slow it; at about 0.1 mM, the two effects cancel each other. Similar results were obtained with muscarinic receptors from the brainstem, but gallamine had only marginal effects on the dissociation of [3H]QNB in the forebrain. On the other hand, verapamil exerts only monophasic effects (slowing) on the dissociation of both [3H]NMS and [3H]QNB from heart receptors and gallamine slows the dissociation of [3H]NMS to a similar extent in all three tissues. Thus, it appears that past discrepancies in the literature can be attributed to the tissues and concentrations of gallamine that were used. Furthermore, the biphasic effects of gallamine suggest that there are multiple allosteric regulatory sites associated with muscarinic receptors.

Allosteric Regulation↗
PubMed1987

Interactions between gallamine and muscarinic receptors: allosterism and subpopulation specificity are separate phenomena.

The quaternary antagonist gallamine discriminates subpopulations of muscarinic receptors in the forebrain and brainstem of the rat and also modulates the binding of other muscarinic ligands via an allosteric mechanism in both brain regions. The calcium channel antagonist verapamil exhibits a similar allosteric effect in both regions (at 100 microM) but does not differentiate the subpopulations that are defined by gallamine. On the other hand, N-methylatropine does not produce the allosteric effect at 100 microM, but shows a high degree of selectivity (about 1,000-fold) for the gallamine-defined subpopulations. These studies indicate that the allosterism and subpopulation specificity of gallamine are separate phenomena and may be examined in isolation by appropriate ligands.

Animals↗
PubMed1985

Patients with pseudoseizures: intellectual and cognitive performance.

We compared cognitive and intellectual performance of patients with pseudoseizures (pseudoseizure-only group), pseudoseizures and epilepsy (mixed seizure group), and generalized epileptic seizures (generalized seizure group). The pseudoseizure-only group performed significantly better on all measures except those of simple motor function. There were no significant differences between those with mixed and generalized seizures. Therefore, cognitive and intellectual performances of patients with pseudoseizures are influenced by the presence or absence of concomitant epilepsy, and suggest that it is necessary to distinguish patients with and without epilepsy in studies of pseudoseizures.

Adolescent↗
PubMed1983

Health professionals' predictions of teenagers' preferences regarding chaperones during physical examinations.

This study assessed the degree of concurrence between teenagers' stated preferences regarding chaperones and professionals' predictions about teenagers' responses. One hundred and fifty members of the Society for Adolescent Medicine received the Method section of a study investigating teenagers' attitudes about chaperones during examination of the genitalia. These professionals were asked to predict the teenagers' choices. Seventy professionals responded. Male and female professionals made highly similar predictions. Professionals' predictions were generally accurate, with four exceptions. Professionals underestimated some teenagers' desire to have a family member present (the case for females aged 14-16 yr and males 12-13 yr). They also underestimated young boys' and girls' reluctance to have an opposite-sexed nurse present. Regarding teenagers' reluctance to be alone with the physician, professionals did not appreciate the differential importance of age for males versus females. They also underestimated, for females and young males, the additive importance of the physician's sex and familiarity to the patient.

Adolescent↗
PubMed1983

Effects of age of onset of partial and generalized seizures on neuropsychological performance in children.

Neuropsychological performance data from 106 children with epilepsy were evaluated to determine the effects of seizure type and age of onset. The performance of children with partial seizures (N = 49) was similar to that of children with generalized seizures (N = 57). Only one of 13 tests showed a significant difference between groups, with children with partial seizures performing better on that test. The effects of age of onset were also similar in the two seizure groups. Children whose seizures began before the age of 5 years performed significantly worse than children whose seizures began later on four measures (Verbal IQ, Performance IQ, Trails A, and Trails B) and performed more poorly, but not significantly so, on the other nine measures in the battery. A breakdown of the partial group into simple partial, complex partial, and secondarily generalized partial seizure groups found a significant difference between the groups on only one variable, but there were suggestions in the data that the performance of the partial secondarily generalized group was worse than the other two groups. These results indicate that variables associated with an early onset of seizures, regardless of type, place a child at risk for cognitive dysfunction.

Age Factors↗
PubMed1983

Improvement in neuropsychological performance in patients with refractory seizures after intensive diagnostic and therapeutic intervention.

Tests of cognitive, perceptual, motor, and memory function were administered to patients with refractory seizures before and after intensive treatment on a specialized epilepsy unit. Improved test performance related to withdrawal of barbiturates and an overall reduction in the number of antiepileptic drugs but not with reduction of seizure frequency.

Adolescent↗
PubMed1981

Test-retest IQ changes of epilepsy patients: assessing the influence of practice effects.

A number of recent studies have emphasized the role of practice effect on test-retest changes in performance often seen on neuropsychological tests. An attempt is made to separate the influence of practice effect from other functional changes in the test-retest differences observed on the WAIS for a sample of adult epilepsy patients. Fifty-eight epilepsy patients were divided into three groups based on their WAIS test-retest score changes. Their corresponding test-retest performance on the Halstead-Reitan Battery and changes in seizure frequency were compared and analyzed. Results indicated that there was a correspondence between improvement in neuropsychological test performance, reduced seizure frequency, and improvement on the WAIS. It was concluded that test-retest changes in neuropsychological test performance reflected changes in psychological functioning of these individuals rather than the influence of practice effect. Some general issues relating to the question of disentangling the influence of practice effect from other functional changes in status were raised and discussed.

Epilepsy↗
PubMed1981

Effects of age of onset of tonic-clonic seizures on neuropsychological performance in children.

Forty-eight children (aged 9 to 15 years) with tonic-clonic seizures were administered a neuropsychological test battery. The children with seizures of early onset (before age 5) were significantly impaired relative to the children with later onset on 8 of the 14 measures in the battery. The deficits were seen on tasks whose requirements included the repetition of a simple motor act, attention and concentration, memory, and complex problem solving. These findings emphasize the need for further research to determine the causal factors of the greater dysfunction seen in the early onset group.

Adolescent↗
PubMed1981

Changes in seizure frequency and test-retest scores on the Wechsler Adult Intelligence Scale.

Test-retest performance on the Wechsler Adult Intelligence Scale (WAIS) of two groups of adult epilepsy patients are presented and compared. In one group, Seizures Improved (SI) group, seizure frequency had decreased during the test-retest interval, and in the other group, Seizures Unimproved (SU) group, the number of seizures had either increased or stayed the same over the test-retest interval. The SI group showed a significant test-retest improvement on WAIS Verbal IQ, Performance IQ, and Full Scale IQ, as well as on eight of 11 WAIS subtests. In comparison, the SU group showed significant increases only on the Performance IQ and Object Assembly subtest. Furthermore, differences between the two groups were observed in the pattern of test-retest changes seen on the Performance measures relative to the Verbal measures. The results suggest that change in seizure frequency is one of the factors associated with test-retest changes in the intellectual functioning of epilepsy patients.

Adolescent↗
PubMed1981

Teenagers' preferences regarding the presence of family members, peers, and chaperones during examination of genitalia.

During physical examination that include the genitalia, teenagers are typically separated from their parents and females are provided with a chaperone. To assess teenagers' attitudes regarding this practice, 140 females and 60 males awaiting treatment in a general adolescent clinic were asked their opinion about a physical examination that include the genitalia. Teenagers indicated whether they would want to be accompanied during the examination, and by whom, as a function of the hypothetical clinical situation that varied the sex and familiarity of the physician. Choices reflected teenagers' age and sex, rather than physician characteristics. Young males and females strongly preferred to be accompanied, generally by a family member. With increasing age, males preferred to be alone with the physician whereas females preferred to be accompanied. Regardless of sex and age, virtually none chose the company of peers. Despite strong development differences, however, there also were pronounced individual differences among teenagers of the same age. Our results suggest that service delivery be adapted to the particular preference expressed by individual teenagers. Needs assessment for adolescent programs may best be achieved by conducting similar surveys in local clinical settings.

Adolescent↗