Neuropsychiatry, neuropsychology, and behavioral neurology最新文献

Objective: To investigate the relation between neuropsychological dysfunction and volumetric measures of neuroanatomic structures in patients with bipolar disorder.

Background: Previous research suggests that neuropsychological deficits are associated with neuroanatomic changes in patients with bipolar disorder.

Method: Twenty-six outpatients who met Diagnostic and Statistical Manual, Third Edition-Revised criteria for bipolar disorder were administered a battery of neuropsychological tests that assessed memory, abstracting ability, psychomotor performance, sustained attention, and intelligence. Patients also received a magnetic resonance imaging scan, from which volumes of the temporal lobes, hippocampus, third ventricle, and areas of the lateral ventricles were calculated. Using multiple regression analyses, neuroanatomic structures were compared with neuropsychological test variables.

Results: Data suggest that a larger right hippocampal volume is associated with poorer neuropsychological functioning.

Conclusions: Further studies are needed to both replicate and examine the relation between potential mechanisms of neuroanatomic alterations and neuropsychological dysfunction in patients with bipolar disorder.

Objective: The goal of this study was to assess the types of auras and their associations with the focus of seizures in 144 consecutive adult patients with partial epilepsy refractory to medical treatment. The association of frequency and type of aura with a psychiatric disorder was also studied.

Background: The nature of the aura, its association with the seizure focus, and its relation with emotions and behavioral dysfunction have received relatively little attention, and remain controversial.

Methods: Patients were admitted to an epilepsy investigation unit for detailed observation of their seizures and type of aura. Patients underwent standard electroencephalographic telemetry, including implanted subdural electrodes, if necessary, to delineate the seizure focus. The auras were classified into nine categories. All patients had an independent clinical psychiatric interview for a Diagnostic and Statistical Manual, Third Edition-Revised (DSM-III-R)-based diagnosis.

Results: Of the 144 patients studied, 111 (77.1%) had one or more symptoms during the aura and 33 (22.9%) had no aura. The most frequent aura types were viscerosensory (47 cases [32.6%]), experiential (44 cases [30.6%]), and cephalic (21 cases [14.6%]). A temporal lobe focus was present in 116 (80.5%) patients. Only experiential auras were significantly associated with a temporal lobe seizure focus (33 of 44 cases). A DSM-III-R psychiatric diagnosis was present in 74 (51.4%) patients. Of the 116 patients with a temporal lobe focus, 60 (50.2%) had a DSM-III-R psychiatric diagnosis. Patients with two or more auras were significantly more likely to have a psychiatric diagnosis (70.2%) compared with those with one aura (39.1%) or no aura (48.5%). A significant association between experiential auras and psychiatric morbidity was seen.

Conclusions: Auras occurred in a majority of patients with a treatment-refractory partial epilepsy who were hospitalized for assessment of their seizure focus for possible surgical candidacy. Two or more auras were associated with a psychiatric diagnosis as was the presence of an experiential aura. Experiential auras were most common in temporal lobe epilepsy. Approximately half the patients, irrespective of seizure focus, had an associated psychiatric morbidity.

Objective: The goal of this study was to examine the convergent validity of informant-rated changes in depressive and related personality traits with clinician-assessed depression in memory-disordered patients.

Background: Depressive symptoms are frequent complications in persons with dementias such as Alzheimer disease, and caregiver informants consistently report changes in depression and related neurotic traits on the NEO Personality Inventory (NEO-PI) in dementia patients.

Methods: In 78 patients undergoing evaluation of memory complaints at an Alzheimer disease clinic, depression was characterized by clinical diagnosis, a clinician-rated scale, and informant ratings of premorbid versus current depression, anxiety, vulnerability, and neuroticism on the NEO-PI.

Results: The diagnostic groups differed in meaningful patterns on the NEO-PI measures. Those with a diagnosis of major depression differed from never-depressed patients in all personality areas, although those with depressed mood differed only on NEO-PI depression. The clinician-rated depression scale correlated modestly with current personality and change from baseline personality.

Conclusions: The NEO-PI provides a useful measure of informants' perspectives on depressive personality changes in patients with memory disorders but does not correspond fully with a clinical syndrome of depression.

Objective: The purpose of the current study was to examine the relation between regional cerebral blood flow (rCBF) and negative symptoms (NS) in patients with dementia of Alzheimer type (DAT).

Background: Negative symptoms in neuropsychiatric disorders were associated with altered rCBF in frontal cortex.

Methods: Twenty-five subjects with a diagnosis of DAT were administered the Scale for the Assessment of Negative Symptoms (SANS), the Positive and Negative Symptom Scale, the Hamilton Rating Scale for Depression, and the Mini-Mental State Examination. The subjects were divided into two groups by means of a median split with regard to NS severity (high NS group, N = 12; low NS group, N = 13). Each patient underwent a single photon emission tomography scan using 99mTc-HMPAO at rest. Cortical and subcortical regions of interest were symmetrically defined in each hemisphere. Cortical-to-cerebellar perfusion ratios were established quantitatively using ADAC software.

Results: High NS group subjects had a significantly lower rCBF than low NS group subjects in the frontal cortex and cingulate gyrus (MANOVA: p = 0.022) as a result of differences in the dorsolateral prefrontal cortex bilaterally (right: F = 12.12, p = 0.002; left: F = 6.55, p = 0.02) and in the frontal cortex, mainly in the right hemisphere (right: F = 6.33, p = 0.02; left: F = 3.26, p = 0.08). For all the subjects (N = 25), there were negative correlations between the SANS total score and rCBF, most prominently in the dorsolateral prefrontal cortex bilaterally (right: r = -0.48, p <0.01; left: r = -0.49, p = 0.01). No significant correlation was found between rCBF in any of the regions of interest and either the Mini-Mental State Examination or the Hamilton Rating Scale for Depression scores.

Conclusions: This study indicates that decreased perfusion in the frontal cortex is associated with NS severity but not with measures of cognitive impairment or depressive symptoms in DAT patients. These results support the hypothesis that the frontal lobes may be involved in the cause of NS in DAT, and they underscore the importance of NS evaluation in neuroimaging studies.

Objective: To examine the relation between dopamine (DA) D2 receptor-specific binding and personality, we assessed the relation between DA D2 binding and the NEO Personality Inventory-Revised (NEO PI-R).

Background: Previous studies have demonstrated a relation between DA D2 receptor-specific binding and a personality trait involving personal detachment as defined by the Karolinska Scales of Personality: A subsequent study using a different measure of personal detachment failed to replicate this finding, suggesting that metric properties of the personality scale may be important. To further examine this issue, we assessed the relation between DA D2 binding and a third personality measure, the NEO PI-R.

Methods: Eighteen adult subjects completed the NEO PI-R and participated in an 11C-raclopride positron emission tomography study to quantify striatal DA D2 receptor binding.

Results: We did not find a significant relation between binding and detachment-like traits on the NEO PI-R; however, we found a significant relation between DA D2 receptor binding and the NEO PI-R personality facet of Depression (r = 0.75, p <0.0001).

Conclusions: The results fail to replicate the findings of previous studies reporting an association between DA D2 receptor density and personal detachment, suggesting that the relation is relatively specific to the trait defined by the Karolinska Scales of Personality. The relation between a nonclinical personality trait of depression and DA D2 binding, if replicated, may help to elucidate the role of dopamine in depression.

Objective: To examine for structural asymmetries in the posterior superior temporal lobe at the microscopic level in an effort to explain the gross anatomical and functional asymmetries of this brain region.

Background: The posterior superior temporal lobe is typically larger on the left and damage to this area frequently results in an aphasia. This has led to the hypothesis that the structural asymmetry determines the functional asymmetry, but no definite confirmation of this hypothesis exists.

Methods: Sixteen men were studied at postmortem. Posterior superior temporal lobe dimensions, gray matter volume, white matter volume, SMI-32 immunopositive neuronal density, and glia cell volume were measured for both the left and right hemispheres. In a subset of eight subjects, myelin sheath and axon diameters were measured with electron microscopy.

Results: Posterior superior temporal lobe white matter volume was greater on the left (p = 0.003, t test for dependent samples). This asymmetry did not appear to be the result of an isolated proliferation of glia (p = 0.46, t test for dependent samples), nor the density of cortical to cortical projections neurons in the overlying cortex (p = 0.71, t test for dependent samples). In a subset of eight subjects studied with electron microscopy, axons of the left posterior superior temporal lobe were more thickly myelinated (57 nm [SD = 27] left, 46 nm [SD = 24], p < 0.001, ANOVA).

Conclusions: As axons with thicker myelin sheaths conduct faster and require a greater volume, these results suggest asymmetry of myelination as an explanation for both a left hemisphere dominance for rapid sensory signal processing, leading to a functional asymmetry for language, and a larger left planum temporale.

Background: Despite advances in the pharmacologic treatment of schizophrenia, the neurophysiologic mechanism(s) of disordered attention in schizophrenia remain elusive.

Objective: The goal of the present study was to assess specific components of attention, including disengagement, movement, re-engagement, and the inhibitory processes involved their control.

Methods: Thirteen chronic schizophrenics from the inpatient and outpatient units of the Veterans Administration Medical Center (New Orleans, LA) and thirteen normal control subjects were administered a saccadic eye movements task. Saccade latency was measured in the presence of contra-lateral distracter stimuli that preceded the target onset (Distracter-before), followed the target onset (Distracter - after) or in the absence of a distracter (No-distracter). In order to assess the interactive process of fixation disengagement and target selection, fixation was either offset before the target (Gap) or it remained on in the presence of the target (Overlap).

Results: Repeated measures analysis of variance revealed that saccadic latency in patients with schizophrenia is prolonged to a greater extent than in normal control subjects in the presence of distracter stimuli. Patients with schizophrenia are also characterized by a greater percentage of error saccades directed to the distracter, and require a longer latency to "issue" corrective saccades following error saccades.

Conclusions: The findings suggest that patients with schizophrenia are required to invoke volitional control under distracter conditions, whereas normal control subjects require minimal volitional control. The results are interpreted in terms of the inhibitory mechanisms that regulate attention.

Objective: This study analyzes lesion configuration in patients in the post-acute stage after first single unilateral stroke who suffered from depressive disorders.

Background: Recent studies indicate a biological origin of poststroke depressive disorders. Due to differences in times of investigation, methods applied, and patient selection, most data are not comparable. Furthermore, only a few studies of poststroke depression report detailed neuropsychologic assessments.

Methods: We investigated 20 consecutive patients who were diagnosed as depressive according to DSM-III-R criteria and exhibited no other severe illness, had no history of neurologic or psychiatric disease, and who were either not aphasic, or only mildly aphasic. A structured clinical interview, self-based and observer-based depression rating scales, a comprehensive neuropsychologic and neurologic examination and ADL-measurement were applied. Neuroradiologic analysis was based on standardized computed tomography scans.

Results: Nine of 10 subjects with left hemisphere strokes exhibited a major depression and 7 of 10 subjects with right hemisphere infarcts a minor depression. The most prominent neuropsychologic deficits were found in frontal lobe associated tasks. Type and severity of depression were not related to the severity of neurologic symptoms or impairment in activities of daily living. For both major and minor depression the maximal overlap of lesions was found in subcortical areas, including parts of the caudate nucleus, posterior parts of the putamen, and the deep white matter.

Conclusions: The findings support the theory that poststroke depression is related to the dysfunction of (cortico-) striato-pallido-thalamic-cortical projections that modulate cortico-thalamo-cortical loop systems.

Objective: To examine the differential impairment of implicit and explicit memory systems in cortical and subcortical dementias.

Background: Whereas verbal priming was reported to be impaired in patients with Alzheimer Disease (AD), patients with Parkinson Disease (PD) may be relatively more impaired on tasks of motor skill learning.

Methods: We examined 15 patients with Alzheimer disease, 10 patients with Parkinson disease and dementia (PD-D), 15 patients with PD but no dementia, and 24 age-comparable normal control subjects with a neuropsychologic battery that included tests of explicit memory (Buschke Selective Reminding Test, Benton Visual Retention Test, Digits Span), and tests of implicit memory (Word-Stem Completion task and the Maze Test).

Results: AD and PD-D groups showed similar deficits on all measures of explicit memory, and performed significantly worse than PD patients without dementia and normal control subjects. On the other hand, there were no significant between-group differences in any of the measures of implicit memory.

Conclusions: Our study demonstrated preserved implicit learning in the context of severe explicit learning deficits in patients with dementia, but could not demonstrate a different profile of memory deficits between so-called cortical and subcortical dementias.