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R J Haier

Publications and source records attributed to R J Haier.

At least 37 records · Page 2Linked to original sources
PubMed1992

Regional glucose metabolic changes after learning a complex visuospatial/motor task: a positron emission tomographic study.

Regional cerebral glucose metabolic rate (GMR) quantified with positron emission tomography (PET) with 18-fluoro-2-deoxyglucose (FDG) was measured twice in 8 young men performing a complex visuospatial/motor task (the computer game Tetris), before and after practice. After 4-8 weeks of daily practice on Tetris, GMR in cortical surface regions decreased despite a more than 7-fold increase in performance. Subjects who improved their Tetris performance the most after practice showed the largest glucose metabolic decreases after practice in several areas. These results suggest that learning may result in decreased use of extraneous or inefficient brain areas. Changes in regional subcortical glucose metabolic rate with practice may reflect changes in cognitive strategy that are a part of the learning process.

Adult↗
PubMed1992

Frontostriatal disorder of cerebral metabolism in never-medicated schizophrenics.

We scanned 18 patients with schizophrenia who had never received neuroleptic medication and 20 age- and sex-matched controls by positron emission tomography with 18-F-fluorodeoxyglucose (fludeoxyglucose F 18) as a tracer of glucose metabolism. Subjects performed the Continuous Performance Test during 18-F-fluorodeoxyglucose uptake. Scan results were converted to metabolic rates, and computer algorithms were used to identify cortical regions. Previous reports of relative hypofrontality in schizophrenia were confirmed, indicating that this finding is not an artifact of previous treatment. Significantly reduced ratios of inferior and medial frontal regions to occipital cortex were found, together with diminished metabolism in the basal ganglia. This suggests the presence of a combined frontostriatal dysfunction in schizophrenia.

Adult↗
PubMed1990

Platelet monoamine oxidase activity and evoked response as predictors of anxiety and depression derived from the content analysis of speech.

Platelet MAO activity has been reported by several investigators to differentiate schizophrenia, schizophrenia related depressive disorders, alcoholism, unipolar and bipolar depression from normal controls. Evoked potentials likewise have differentiated schizophrenic and affective patients. However, the precise relationship between MAO activity, evoked potentials (EP), and psychiatric illness has not been clarified. A possible association between psychopathology and high MAO activity/EP reducing and low MAO activity/EP augmenting has been reported. Such a bidirectionality further confounds results. This study was undertaken to determine the association of psychopathological dimensions found in a group of subjects whose platelet MAO activity and evoked responses were obtained two years earlier. Utilizing the Gottschalk-Gleser verbal behavior scales of Anxiety, Depression, Social Alienation-Personal Disorganization and Cognitive Impairment a significant correlation was revealed between low platelet MAO activity and high Total Anxiety scale and Shame Anxiety subscale scores. Additionally, a significant correlation was demonstrated between reducing evoked potentials and elevated Death Anxiety, Somatic Concerns, and Total Death and Mutilation Depression subscales scores, combined and separately. Furthermore, a significant positive correlation was found between augmenting evoked potentials and Overt Hostility Outward scores. No significant correlations were demonstrated between platelet MAO activity or evoked potentials and Social Alienation-Personal Disorganization or Cognitive Impairment scores. These findings lend support to the position that biological markers may predict predispositions to anxiety and depression.

Adult↗
PubMed1990

Platelet MAO activity in personality disorders and normal controls.

Platelet monoamine oxidase (MAO) activity has been related to several psychiatric disorders and personality dimensions. The purpose of this study was to measure platelet MAO activity in personality disorders and determine its relationship to symptoms analogous to sensation seeking. Twenty-eight males admitted to a psychiatric unit with a DSM-III-R diagnosis of personality disorder were compared to normal controls. Patients with Axis I diagnoses other than adjustment disorder were excluded. There was no difference in MAO activity between patients and normals, although it was lower in borderline patients. MAO activity was inversely correlated with sensation seeking, especially in the patient group, as predicted. The results are consistent with the view that platelet MAO activity is a marker of general psychopathology.

Adjustment Disorders↗
PubMed1990

Glucose metabolic rate in normals and schizophrenics during the Continuous Performance Test assessed by positron emission tomography.

Local cerebral uptake of glucose labelled with fluorine-18 was measured by positron emission tomography in 13 patients with schizophrenia and 37 right-handed volunteers. Patients received no medication for a minimum of 31 days and a mean of 30 weeks. The subjects were administered the labelled deoxyglucose just after the beginning of a 32-minute sequence of blurred numbers as visual stimuli for the Continuous Performance Test. In normal controls, task performance was associated with increases in glucose metabolic rate in the right frontal and right temporoparietal regions; occipital rates were unchanged. Patients with schizophrenia showed both absolutely and relatively reduced metabolic rates in the frontal cortex and in the temporoparietal regions compared with normal controls.

Adult↗
PubMed1989

Topographic evoked potential mapping in obsessive-compulsive disorder: evidence of frontal lobe dysfunction.

Several lines of evidence suggest that frontal lobe dysfunction may underlie obsessive-compulsive disorder (OCD). Eighteen patients with OCD were compared with 18 normals matched for age, gender, handedness, and education on a Go-NoGo task. Visual evoked potentials were measured during the task. Topographic evoked potential mapping revealed significantly smaller P300 magnitudes in orbital frontal areas in the OCD patients. Results are compared with those from studies using other methodologies, and etiological implications are discussed.

Adult↗
PubMed1989

A controlled trial of desipramine in 18 men with posttraumatic stress disorder.

Eighteen male U.S. veterans meeting DSM-III criteria for posttraumatic stress disorder (PTSD) completed a 4-week double-blind, crossover study comparing administration of 200 mg/day of desipramine with placebo. Response was measured by using the Beck Depression Inventory, the Hamilton Rating Scale for Depression, the Hamilton Rating Scale for Anxiety, and the Impact of Event Scale. Overall, the only apparent response to desipramine was in some symptoms of depression; there were no changes in anxiety and other PTSD symptoms.

Adult↗
PubMed1988

Biological vulnerability to depression: replication of MAO and evoked potentials as risk factors.

In previous work, we have reported that specific combinations of platelet (MAO) activity and evoked potential augmenting/reducing (AR) are associated with risk for affective disorders. This new study screened 271 college freshmen solely on MAO and AR and selected a sample with extreme values on both measures. These students were interviewed with the Diagnostic Interview Schedule and they completed a family history questionnaire and psychosocial scales. Following the previous work, the same MAO and AR combinations were related to the frequency of major depression and a family history of psychiatric disorder.

Adolescent↗
PubMed1988

Assessment of young men at risk for alcoholism with P300 from a visual discrimination task.

A visual discrimination paradigm was used to elicit the P3 (P300) component of the event-related brain potential (ERP) in a large group (N = 196) of male undergraduate volunteers. Comparison of P3 amplitude and latencies between individuals with a positive family history for alcoholism (FH +) and those without such a history (FH -) obtained no differences between the groups. No associations between P3 latency or amplitude and the amount of alcohol typically consumed were found. Differences between the present and previous P3 family history studies using visual stimuli are attributed to the cognitive demands of ERP task.

Adult↗
PubMed1987

Functional and anatomical brain imaging: impact on schizophrenia research.

A group of related new technologies has made it possible to study the brain's regional changes in metabolism, blood flow, electrical activity, and neurochemistry. Positron emission tomography (PET) produces slice images of radioisotope density--brain metabolism or receptor concentration can be quantitated. Studies in schizophrenia have indicated relative metabolic underactivity of the frontal lobes of schizophrenics. Decreased activity in the basal ganglia, which can be reversed with neuroleptic treatment, is also seen in schizophrenia. PET studies are in the early stages; standard methodology for isotope selection, task during tracer uptake, and quantitative analysis is still developing. Cerebral blood flow studies have shown similar patterns in the cortical surface. The electroencephalogram provides a short time resolution approach which can assess attention and arousal, but lacks some of the anatomic exactness and depth capabilities of PET. Magnetic resonance imaging furnishes anatomical images of gray and white matter previously unavailable with x-ray computed tomography. Advances in methodology and clinical studies with imaging are making neuroanatomic theories of schizophrenia more directly testable than ever before.

Attention↗
PubMed1987

Biological markers of affective disorders and posttraumatic stress disorder: a pilot study with desipramine.

Three biological markers of affective disorders and response to desipramine were used to study the relationship of posttraumatic stress disorder (PTSD) to affective illness. Blunted TRH response and decreased REM latency in eight patients with PTSD occurred at frequencies similar to those that have been found in patients with major affective disorder. Pretreatment Hamilton Rating Scale for Depression and Beck Depression Inventory scale scores were elevated; scores after 4 weeks' treatment with desipramine revealed significant (p less than .05 and p less than .005, respectively) improvement. These findings support a link between PTSD and affective illness.

Adult↗
PubMed1985

Attention dysfunction and psychopathology in college men.

Four hundred college men were screened on a measure of vigilance, the Continuous Performance Test (CPT). The individuals with good and poor attention (the upper and lower 5% of the CPT score distribution) were compared on multiple measures of psychiatric disturbance, cognition, and psycho-physiologic function. The attention dysfunction group (lower 5%) had a higher incidence of symptoms of hyperactivity both in childhood and as adults, but had no higher incidence of other psychopathology as assessed with either the Research Diagnostic Criteria or the Minnesota Multiphasic Personality Inventory. Cognitive differences between the lower and upper CPT groups, including differences on Wechsler Adult Intelligence Scale subtests, the Stroop test, reaction time, and evoked potentials, substantiated an attention dysfunction syndrome. Thus, attentional dysfunction in young adults seems more closely linked to hyperactivity than to current psychopathology.

Adolescent↗
PubMed1985

Diagnostic heterogeneity and the DST in consecutive psychiatric admissions.

There is uncertainty about the clinical usefulness of the dexamethasone suppression test (DST). It is also unclear whether there are advantages to a 1-mg or 2-mg DST. Eighty-three consecutive psychiatric inpatients were randomly given a 1-mg or 2-mg DST within the first week of admission. Sensitivity, specificity, and diagnostic confidence are reported for this group, and also in combination with those for 119 semi-consecutive psychiatric admissions. Although rates of nonsuppression were consistently higher in patients with affective disorders than in patients with other diagnoses, the diagnostic confidence of the DST for major depression in a diverse and unselected patient population was not greater than the prevalence of the disorder. The DST does not appear to be useful for clinical diagnostic decision-making. Nonetheless, the DST may still be an important biological marker in neuroendocrine psychiatric research.

Adult↗
PubMed1984

Evoked potential augmenting and reducing: the methodological and theoretical significance of new electrophysiological observations.

Buchsbaum's (1976) evoked potential (EP) procedure reveals differences in the slope of P100-N140 amplitude changes with variation of stimulus luminance. Subjects are classed 'augmenters' or 'reducers', respectively, if their slopes are positive or negative. Psychological correlates of this slope index have been reported and it has distinguished psychiatric patient populations from healthy subjects. Data are presented which indicate that the augmenting-reducing slope differences are due to an early slow-wave. For augmenters, the major slow-wave deflection is of positive polarity. At the highest luminance, with a correspondingly shorter latency, the slow-wave increases the positive-going P100 deflection. At the lowest luminance, with a longer latency, it reduces the negative-going N140 deflection. This results in positive slopes. For reducers, the major slow-wave deflection is of negative polarity. This influences the measured P100 and N140 amplitudes in a manner opposite to that described for augmenters and results in negative slopes. Since these findings provide new insights concerning the nature of the Buchsbaum augmenting-reducing phenomenon, they have methodological and theoretical implications. It is concluded that the Buchsbaum procedure is an effective measure of slow-wave differences but that the reducing effect is difficult to explain in terms of Pavlov's concept of protective inhibition. An alternative 'opponent-process' explanation is offered.

Brain↗
PubMed1984

Isosafrole and schizophrenia-like psychosis.

A 19-year-old man developed a schizophrenia-like psychosis after ingesting isosafrole. His use of amphetamines and LSD failed to produce a similar syndrome. Isosafrole may provide another biochemical model for schizophrenia.

Adult↗
PubMed1983

Pain sensitivity, evoked potentials, and the dexamethasone suppression test in depressed patients.

Nonsuppression of cortisol following dexamethasone may identify a biologically homogeneous subgroup of psychiatric patients. This article reports two studies examining pain sensitivity and sensory inhibition measured by evoked potential augmenting/reducing in dexamethasone test (DST) suppressors and nonsuppressors. Since nonsuppression may be related to elevated levels of adrenocorticotropic hormone (ACTH) and, perhaps, endogenous opiates, pain sensitivity and augmenting/reducing may differ between suppressors and nonsuppressors. Results indicate that nonsuppressors lack sensory inhibition and that evoked potential augmenting/reducing is correlated strongly with pain sensitivity only in nonsuppressors. These results are consistent with the hypothesis that the DST identifies biologically different subgroups of depression.

Adult↗
PubMed1983

Pain sensitivity and obesity.

Endogenous opiates have been implicated as regulators of mood and pain. Recent literature suggests a relationship between these internal opiates and ingestive behaviors in both animals and humans. The present study investigates this relationship by comparing the pain sensitivities of obese and nonobese subjects. Twenty-six subjects (18 females, 8 males) whose weight was 130% or greater of their ideal body weight (IBW) constituted the obese experimental group, while 34 subjects (14 females, 20 males) whose weight was less than 130% IBW formed the nonobese control group. Volunteer subjects were sought from a general medicine clinic of a hospital. Each subject placed his index finger in a pressure device bearing a 3-pound weight and was instructed to report the first occurrence of pain and the desire to remove the finger from the device. Obese subjects were significantly more pain sensitive. The difference in pain sensitivities supports the hypothesis that the weight difference between the obese and nonobese subjects may be related to endogenous opiate control of ingestive behaviors.

Adult↗