SPECT study of visual fixation in schizophrenia and comparison subjects

Malaspina, Dolores; Storer, Stephen; Furman, Vitaly; Esser, Peter D.; Printz, David; Berman, Ariela; Lignelli, Angela; Gorman, Jack M.; Heertum, Ronald Van

doi:10.1016/s0006-3223(98)00306-0

Cited by 62 publications

(44 citation statements)

References 41 publications

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“…Like the medial prefrontal cortex, the fusiform gyrus shows abnormal volume and blood flow in persons with schizophrenia. Both McDonald et al (122) and Paillere-Martinot et al (102) found smaller regional gray matter in the left fusiform gyrus of individuals with schizophrenia in relation to healthy comparison subjects, and Malaspina and colleagues (106) reported increased rCBF in the right fusiform gyrus during a visual fixation task. Although the latter finding may initially seem counterintuitive, one must consider that increased rCBF was not present in healthy comparison participants and, in this respect, may indicate an abnormality in individuals with schizophrenia.…”

Section: Facial and Emotion Processingmentioning

confidence: 95%

“…Along with smaller volumes, functional imaging has revealed decreased regional (r)CBF in the left medial frontal gyrus (Brodmann's area 9) during a cognitively nondemanding visual fixation task (106), in the left medial prefrontal cortex during the Wisconsin Card Sorting Test, and in both the left and right medial prefrontal cortex during test and rest conditions among persons with schizophrenia (107). Finally, persons with schizophrenia show evidence of hypoactivity of the right medial prefrontal cortex during cognitive tasks such as time estimation and frequency discrimination (108).…”

Section: The Frontal Cortices and The Theory Of Mindmentioning

confidence: 99%

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Implications for the Neural Basis of Social Cognition for the Study of Schizophrenia

Pinkham

Penn²,

Perkins³

et al. 2003

AJP

394

228

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Section: Facial and Emotion Processingmentioning

confidence: 95%

Section: The Frontal Cortices and The Theory Of Mindmentioning

confidence: 99%

Implications for the Neural Basis of Social Cognition for the Study of Schizophrenia

Pinkham

Penn²,

Perkins³

et al. 2003

AJP

394

228

View full text Add to dashboard Cite

show abstract

“…Thus, as reviewed above, in the schizophrenia patient the DA system is in a hyper-responsive state, with abnormal levels of DA release occurring to stimuli when contrasted with control conditions. Moreover, there is increasing evidence that the anterior hippocampus (the human homolog of the ventral subiculum) is overactive in schizophrenia patients (Malaspina et al, 1999;Kegeles et al, 2000;Heckers, 2001;Medoff et al, 2001;Meyer-Lindenberg et al, 2005).…”

Section: Abnormal Drive Of the Dopamine System In Schizophreniamentioning

confidence: 99%

Dopamine System Dysregulation by the Ventral Subiculum as the Common Pathophysiological Basis for Schizophrenia Psychosis, Psychostimulant Abuse, and Stress

Grace¹

2010

Staging Neuropsychiatric Disorders

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The dopamine system is under multiple forms of regulation, and in turn provides effective modulation of system responses. Dopamine neurons are known to exist in several states of activity. The population activity, or the proportion of dopamine neurons firing spontaneously, is controlled by the ventral subiculum of the hippocampus. In contrast, burst firing, which is proposed to be the behaviorally salient output of the dopamine system, is driven by the brainstem pedunculopontine tegmentum. When an animal is exposed to a behaviorally salient stimulus, the pedunculopontine tegmentum elicits a burst of action potentials in the dopamine neurons. However, this bursting only occurs in the portion of the dopamine neuron population that is firing spontaneously. This proportion is regulated by the ventral subiculum. Therefore, the ventral subiculum provides the gain, or the amplification factor, for the behaviorally salient stimulus. The ventral subiculum itself is proposed to carry information related to the environmental context. Thus, the ventral subiculum will adjust the responsivity of the dopamine system based on the needs of the organism and the characteristics of the environment. However, this finely tuned system can be disrupted in disease states. In schizophrenia, a disruption of interneuronal regulation of the ventral subiculum is proposed to lead to an overdrive of the dopamine system, rendering the system in a constant hypervigilant state. Moreover, amphetamine sensitization and stressors also appear to cause an abnormal dopaminergic drive. Such an interaction could underlie the risk factors of drug abuse and stress in the precipitation of a psychotic event. On the other hand, this could point to the ventral subiculum as an effective site of therapeutic intervention in the treatment or even the prevention of schizophrenia.Schizophrenia is a devastating disorder that arises during late adolescence/early adulthood. This disorder is characterized by a spectrum of disruptions, including disruption of perceptions and hallucinations, thought disorder, and cognitive disturbances. Schizophrenia has been shown to be genetically linked, in that the propensity for an individual to develop schizophrenia is related to the proportion of shared genetic material Shields, 1971, 1976). Nonetheless, it is clear that this disorder is not completely genetically determined. Thus, investigators have found a number of risk factors that predispose an individual to schizophrenia, or alternately can lead to exacerbation of psychosis or relapse in those individuals in which the schizophrenia is in remission, including stress, perinatal factors, environmental factors, and drug abuse (Jones et al., 1994;Hultman et al., 1999;McDonald and Murray, 2000). However, how such risk factors can interact with a genetic predisposition to facilitate transition to psychosis, or what common neurobiological substrates underlie this comorbidity, is unknown. Using studies in a rat model of schizophrenia, we found that risk factors such as stress...

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“…We have previously reported this perfusion pattern for medication-free schizophrenia patients for a resting visual fixation task. 35 A theory of imbalance or disconnection between the frontal cortex and the medial temporal lobe has been proposed to account for schizophrenia, 36 and such abnormalities have been demonstrated in other PET and SPECT studies. 37 The right-sided cortical-subcortical hypermetabolism we found for the diminished-REApatients might normalize with clinical improvement.…”

Section: Dichotic Listening Subgroupsmentioning

confidence: 99%

Schizophrenia Subgroups Differing in Dichotic Listening Laterality Also Differ in Neurometabolism and Symptomatology

Malaspina

Bruder²,

Furman³

et al. 2000

JNP

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Schizophrenia patients vary in right ear advantage (REA) on dichotic listening tests for assessing left hemispheric dominance for language processing. The authors examined if patients with low REA differed from other patients in symptoms and in resting brain metabolism. SPECT was conducted during visual fixation for 9 healthy control subjects and 16 schizophrenia patients: 8 with normal and 8 with diminished REA. REA-diminished patients had greater positive symptoms and lower mental status scores (all P<0.05) and had right middle temporal gyrus hypermetabolism. Both schizophrenia groups had decreased right frontal and increased medial temporal lobe metabolism vs. control subjects. REA-diminished patients had right temporal lobe hypermetabolism under a resting condition (eyes open, visual fixation). Results suggest reduced right ear (left hemisphere) advantage for dichotic word perception in schizophrenia is related to a predisposition to overactivate right temporal lobe regions and to positive symptoms. In contrast, the prefrontal-medial temporal imbalance present in both patient groups may typify the schizophrenia syndrome.

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SPECT study of visual fixation in schizophrenia and comparison subjects

Cited by 62 publications

References 41 publications

Implications for the Neural Basis of Social Cognition for the Study of Schizophrenia

Implications for the Neural Basis of Social Cognition for the Study of Schizophrenia

Dopamine System Dysregulation by the Ventral Subiculum as the Common Pathophysiological Basis for Schizophrenia Psychosis, Psychostimulant Abuse, and Stress

Schizophrenia Subgroups Differing in Dichotic Listening Laterality Also Differ in Neurometabolism and Symptomatology

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