PubMed Health⌕ Search

Biomedical subjects

S Berent

Publications and source records attributed to S Berent.

At least 19 recordsLinked to original sources
PubMed1992

Hippocampal formation volume, memory dysfunction, and cortisol levels in patients with Cushing's syndrome.

Patients with chronic hypercortisolemia due to Cushing's syndrome (CS) exhibit cognitive dysfunction. Because glucocorticoid excess is associated with hippocampal damage in animals, and the hippocampus participates in learning and memory, we explored the relationships between hippocampal formation (HF) volume, memory dysfunction, and cortisol levels in 12 patients with CS. After magnetic resonance imaging, HF volume was determined using digital sum of track ball traces of dentate gyrus, hippocampus proper and subiculum, correcting for total intracranial volume. For 27% of the patients, HF volume fell outside the 95% confidence intervals for normal subject volume given in the literature. In addition, there were significant and specific correlations between HF volume and scores for verbal paired associate learning, verbal recall, and verbal recall corrected for full-scale IQ (r = 0.57 to 0.70, p < 0.05). HF volume was negatively correlated with plasma cortisol levels (r = -0.73, p < 0.05). These studies suggest an association between reduced HF volume, memory dysfunction, and elevated cortisol in patients with CS.

Adolescent↗
PubMed1992

Verbal fluency and positron emission tomographic mapping of regional cerebral glucose metabolism.

Impairment in verbal fluency (VF) has been a consistently reported clinical feature of focal cerebral deficits in frontal and temporal regions. More recent behavioral activation studies with healthy control subjects using positron emission tomography (PET), however, have noted a negative correlation between performance on verbal fluency tasks and regional cortical activity. To see if this negative relationship extends to steady-state non-activation PET measures, thirty-three healthy adults were given a VF task within a day of their 18F-2-fluoro-2-deoxy-D-glucose PET scan. VF was found to correlate positively with left temporal cortical region metabolic activity but to correlate negatively with right and left frontal activity. VF was not correlated significantly with right temporal cortical metabolic activity. Some previous studies with normals using behavioral activation paradigms and PET have reported negative correlations between metabolic activity and cognitive performance similar to that reported here. An explanation for the disparate relationships that were observed between frontal and temporal brain areas and VF might be found in the mediation of different task demands by these separate locations, i.e., task planning and/or initiation by frontal regions and verbal memory by the left temporal area.

Adult↗
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

Longitudinal sensitivity of the Fuld cholinergic profile to Alzheimer's disease.

The diagnostic sensitivity of a profile (Fuld, 1984) thought to mark cholinergic changes in Alzheimer's Disease (AD) was examined in a sample of 53 patients meeting criteria for AD on two occasions and in 19 patients for three occasions. The low obtained sensitivities of the Fuld profile (17%-26%) across testings is consistent with previous studies that used a single time point. The findings also revealed unstable positive and negative profiles over time. There were no performance differences on intellectual or memory measures when comparing subjects identified as positive or negative by the Fuld index. The results demonstrate that the index is insensitive to the dementing process and is a poor diagnostic marker for AD.

Aged↗
PubMed1992

Progressive subcortical gliosis and progressive supranuclear palsy can have similar clinical and PET abnormalities.

In studies of cerebral glucose metabolism utilising positron emission tomography (PET) with 18F-fluoro-2-deoxy-D-glucose, patients with the clinical picture of progressive supranuclear palsy (PSP) have shown predominantly frontal glucose hypometabolism. This is presumed to represent deafferentation of cerebral cortical from subcortical structures. In these studies, however, the diagnosis of PSP has not been verified by pathological examination. Necropsy examinations were performed in three patients with the clinical features of PSP in whom PET had demonstrated predominantly frontal hypometabolism. In two of these patients the diagnosis of PSP was confirmed pathologically, and no morphological abnormalities were found in the cerebral cortex. The third patient had extensive cortical and subcortical neuronal loss and gliosis without neurofibrillary tangles, consistent with the diagnosis of progressive subcortical gliosis (PSG). Even in retrospect no unique clinical neurological abnormality or finding on laboratory investigation could be identified that distinguished this latter patient from those with pathologically confirmed PSP. We conclude that PSG and PSP may be indistinguishable during life, and necropsy confirmation is needed for definite diagnosis.

Blood Glucose↗
PubMed1990

Neuropsychological changes in olivopontocerebellar atrophy.

We used standardized neuropsychological measures of intellectual, cognitive, psychomotor, and emotional functioning to compare 39 patients with olivopontocerebellar atrophy and 25 normal controls of similar age. The patients reflected greater depression, anxiety, and subjective emotional discomfort than did the control subjects. While 4 of the patients had below-normal IQ scores (Wechsler Adult Intelligence Scale [WAIS-R] Full-Scale IQ [FSIQ] less than 80), their clinical histories suggested lifelong functioning at such levels. As a group, the patients were not abnormal in general intellectual functioning and related cognitive abilities (WAIS-R FSIQ, mean [+/- SD], 93.46 +/- 13.19; Wechsler Memory Scale mental quotient, 108.95 +/- 17.43). These scores were lower than those of the normal controls (WAIS-R FSIQ, 113.72 +/- 12.68; mental quotient, 127.80 +/- 12.40); however, the controls were a highly educated group with intelligence levels that were higher than those of the average population. Moreover, when education and motor dysfunction were statistically covaried, no significant differences between the patients and the normal controls were apparent on the cognitive and intellectual tasks. Further analysis of specific memory performance in a subgroup of patients and controls matched for age, sex, and education yielded findings that were comparable with the overall group analysis. We conclude that motor dysfunction and depressed mood could leave patients with olivopontocerebellar atrophy appearing to be impaired in memory, even demented, when they are not.

Adult↗
PubMed1990

Cerebellar and frontal hypometabolism in alcoholic cerebellar degeneration studied with positron emission tomography.

Local cerebral metabolic rate for glucose was studied utilizing 18F-2-fluoro-2-deoxy-D-glucose and positron emission tomography (PET) in 14 chronically alcohol-dependent patients and 8 normal control subjects of similar age and sex. Nine of the 14 patients (Group A) had clinical signs of alcoholic cerebellar degeneration, and the remaining 5 (Group B) did not have signs of alcoholic cerebellar degeneration. PET studies of Group A revealed significantly decreased local cerebral metabolic rates for glucose in the superior cerebellar vermis in comparison with the normal control subjects. Group B did not show decreased rates in the cerebellum. Both Groups A and B showed decreased local cerebral metabolic rates for glucose bilaterally in the medial frontal area of the cerebral cortex in comparison with the normal control subjects. The severity of the clinical neurological impairment was significantly correlated with the degree of hypometabolism in both the superior cerebellar vermis and the medial frontal region of the cerebral cortex. The degree of atrophy detected in computed tomography scans was significantly correlated with local cerebral metabolic rates in the medial frontal area of the cerebral cortex, but not in the cerebellum. The data indicate that hypometabolism in the superior cerebellar vermis closely follows clinical symptomatology in patients with alcoholic cerebellar degeneration, and does not occur in alcohol-dependent patients without clinical evidence of cerebellar dysfunction. Hypometabolism in the medial frontal region of the cerebral cortex is a prominent finding in alcohol-dependent patients with or without alcoholic cerebellar degeneration.

Adult↗
PubMed1990

Anxiety and cerebral cortical metabolism in normal persons.

The State-Trait Anxiety Inventory (STAI) was administered to 43 normal volunteers immediately before and after a positron emission tomography (PET) procedure with [18F]-2-fluoro-2-deoxy-D-glucose (18F-FDG). High trait-anxious individuals had significantly higher state (situational) anxiety associated with the PET scan procedure than did low trait-anxious persons. State anxiety decreased significantly for all respondents following the PET scan procedure. No significant relationships between global or regional cortical metabolic rates and state anxiety were observed. The direct cortical metabolic effects of heightened anxiety in the scan setting, should they exist, are likely obscured in the normal variance of the 18F-FDG method.

Adolescent↗
PubMed1990

The utility and generality of Mini-Mental State Examination scores in Alzheimer's disease.

The present study sought to evaluate the validity and generality of the Mini-Mental State Examination (MMSE) and its subsection scores. We gave the MMSE and other neuropsychological tests to 51 patients with probable Alzheimer's disease. On the basis of correlational and factor analyses, overall performance on the MMSE proved to have good concurrent validity with other comprehensive neuropsychological assessment instruments. However, the MMSE subsections should not be viewed as highly specific measures of cognition or memory.

Aged↗
PubMed1989

A controlled study of neuropsychological deficits in acute spinal cord injury patients.

According to a number of studies, between 40% and 60% of acute traumatic spinal cord injury (SCI) patients demonstrate cognitive dysfunction resulting from various forms of cerebral damage, including concurrent or premorbid closed head injury, chronic alcohol or substance abuse, and other causes. However, applicability of findings from these reports has been limited due to the use of inadequate neuropsychological testing techniques and the lack of control data. In a collaborative investigation, 81 acute SCI patients and 61 non-injured control subjects between 18 and 55 years of age completed a comprehensive motor-free neuropsychological test battery, including: Halstead Category Test (HCT), Vocabulary Subtest (VOCAB) of the Wechsler Adult Intelligence Scale - Revised; Mental Control (MC) Subtest, and Initial and Recall trials of Logical Memory (LM) and Paired Associates (PA) Subtests of the Wechsler Memory Scale; and the 8 trials of the Rey Auditory Verbal Learning Test (RAVLT). Percentages of retained information on the LM and PA were also calculated. Impairment levels for each test were defined as values which exceeded two standard deviations (one-tailed) from the control mean. Based on this definition, the prevalence of neuropsychological abnormality on each test ranged between 10% and 40%. Mean performance levels of patients were significantly more impaired than those of control subjects for all tests except for the Interference trial of the RAVLT and for the percentages of retained information on the LM and PA subtests. Comparison of test results of SCI patients with those of control subjects demonstrates that poor attention span and limited initial learning ability are frequent problems among SCI patients. Other common neuropsychological deficits among these patients include poor concentration ability, impaired memory function, and altered problem solving ability. These deficits may interfere with rehabilitation following SCI.

Adolescent↗
PubMed1989

Failure of cholinergic agonist RS-86 to improve cognition and movement in PSP despite effects on sleep.

Postmortem studies of patients with progressive supranuclear palsy (PSP) have demonstrated loss of cholinergic neurons in the striatum, nucleus basalis of Meynert, and the pedunculopontine nucleus. These findings suggest that cholinergic drugs might be an effective treatment for this disease. We studied the efficacy of RS-86, a direct cholinergic agonist, upon motor abilities, eye movements, and psychometric performance in 10 patients with PSP during a 9-week placebo-controlled, double-blinded, crossover trial. Glycopyrrolate, a peripheral anticholinergic drug, was given throughout the trial to minimize cholinergic side effects. We used changes in rapid eye movement (REM) sleep to assess the degree of cholinergic activation achieved by treatment. Despite the enhancement of cholinergic activity in the CNS as indicated by increases in REM sleep latency and REM sleep time, RS-86 did not improve motor signs, eye movements, or cognition. Pharmacologic replacement of the cholinergic deficits in PSP does not result in significant clinical benefit.

Aged↗
PubMed1988

Positron emission tomographic scan investigations of Huntington's disease: cerebral metabolic correlates of cognitive function.

Fifteen drug-free patients with early to mid-stage Huntington's disease (HD) were evaluated with positron emission tomographic (PET) scans of 18F-2-fluoro-2-deoxy-D-glucose uptake and quantitative measures of neurological function, learning, memory, and general intelligence. In comparison with a group of normal volunteers, the HD patients showed lower metabolism in both caudate (p less than 0.001) and putamen (p less than 0.001) on PET scans. A significant and positive relationship was found between neuropsychological measures of verbal learning and memory and caudate metabolism in the patient group but not in the normal group. Visual-spatial learning did not reflect a similar pattern, but performance intelligence quotient was positively related to both caudate and putamen metabolism in the HD group. Vocabulary level was unrelated to either brain structure. Discussion focuses on these and other observed brain-behavior relationships and on the implications of these findings for general behaviors such as those involved in coping and adaptation.

Adult↗
PubMed1988

Cerebral hypometabolism in progressive supranuclear palsy studied with positron emission tomography.

Progressive supranuclear palsy (PSP) is characterized by supranuclear palsy of gaze, axial dystonia, bradykinesia, rigidity, and a progressive dementia. Pathological changes in this disorder are generally restricted to subcortical structures, yet the type and range of cognitive deficits suggest the involvement of many cerebral regions. We examined the extent of functional impairment to cerebral cortical and subcortical structures as measured by the level of glucose metabolic activity at rest. Fourteen patients with PSP were compared to 21 normal volunteers of similar age using 18F-2-fluoro-2-deoxy-D-glucose and positron emission tomography. Glucose metabolism was reduced in the caudate nucleus, putamen, thalamus, pons, and cerebral cortex, but not in the cerebellum in the patients with PSP as compared to the normal subjects. Analysis of individual brain regions revealed significant declines in cerebral glucose utilization in most regions throughout the cerebral cortex, particularly those in the superior half of the frontal lobe. Declines in the most affected regions of cerebral cortex were greater than those in any single subcortical structure. Although using conventional neuropathological techniques the cerebral cortex appears to be unaffected in PSP, significant and pervasive functional impairments in both cortical and subcortical structures are present. These observations help to account for the constellation of cognitive symptoms in individual patients with PSP and the difficulty encountered in identifying a characteristic psychometric profile for this group of patients.

Aged↗
PubMed1988

Closed head injury in acute traumatic spinal cord injury: incidence and risk factors.

Investigators estimate that 15% to 50% of all patients with spinal cord injury (SCI) also incur a closed head injury (CHI), but studies have been hampered by design flaws, including retrospective assessment and inconsistent definition of CHI. We conducted a prospective study of combined CHI and SCI among 82 SCI patients consecutively admitted at two hospitals within 24 hours of injury. The purpose of the study was to determine the incidence and duration of loss of consciousness and posttraumatic amnesia (PTA), and to establish the risk factors for combined CHI and SCI. The overall incidence of CHI as defined by the presence of PTA of any duration was 49%. There was a significantly increased risk of CHI for patients involved in traffic accidents (risk ratio = 3.7; 95% confidence interval 1.8 to 7.2). There was no increased risk associated with level of injury (quadriplegic vs paraplegic; risk ratio = 1.2; 95% confidence interval = 0.8 to 1.8). All SCI patients, regardless of level of injury, deserve systematic evaluations for CHI in their acute care evaluations.

Adult↗
PubMed1988

Galveston Orientation and Amnesia Test: its utility in the determination of closed head injury in acute spinal cord injury patients.

The incidence of closed head injury (CHI) associated with acute spinal cord injury (SCI) has been estimated at 40% to 50%. Closed head injury can be defined as the presence of loss of consciousness (LOC) and/or posttraumatic amnesia (PTA). Consequently, one of the difficulties in establishing a diagnosis of CHI is determining the existence of PTA in those patients without documented LOC. Previous work described the inconsistent evaluation of PTA in the SCI population. This study was conducted to evaluate the utility of the Galveston Orientation and Amnesia Test (GOAT) in establishing the diagnosis of CHI in a series of acute traumatic SCI patients. The GOAT was administered serially for three to five days to 34 patients admitted to our hospital. When information derived from the GOAT was added to that derived from review of medical records alone, the observed incidence of PTA (and by implication CHI) increased significantly (McNemar statistic = 6.4; p = 0.01). The GOAT is a quick, simple, and reproducible evaluation of spheres of orientation, which is extremely helpful in diagnosis of PTA in this population. This instrument should be used to evaluate patients at high risk for head injury. Although abnormalities in the GOAT evaluation may also be attributable to factors other than CHI (eg, hypoxia, medication effects), such findings provide evidence suggestive of CHI. This will help determine which patients require a more detailed neuropsychologic assessment.

Adult↗
PubMed1987

Normal caudate glucose metabolism in persons at risk for Huntington's disease.

Glucose metabolism was examined by positron emission tomographic scanning with F-2-fluoro-2-deoxy-D-glucose in 29 persons at risk for Huntington's disease (HD), 28 age-matched controls, nine patients with stage I, and eight patients with stage II symptomatic HD. Absolute caudate metabolic rates and normalized indexes of caudate metabolism for at-risk persons were normal compared with controls. No at-risk person had caudate indexes outside two SDs of the controls' mean. Caudate metabolism in the earliest HD cases was significantly reduced compared with controls and at-risk persons, but within the 99% confidence levels of both groups. Stage II patients had caudate measures that were significantly depressed compared with those of stage I HD patients. Measurement of caudate glucose hypometabolism is unlikely to be sufficiently sensitive to serve as a presymptomatic marker of heterozygote status, although it will provide a sensitive marker for progressive caudate dysfunction in HD.

Adult↗