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G M Goodwin

Publications and source records attributed to G M Goodwin.

At least 73 records · Page 4Linked to original sources
PubMed1995

Hypofrontality revisited: a high resolution single photon emission computed tomography study in schizophrenia.

Hypofrontality or reduced activity in the prefrontal cortex, measured as reduced frontal perfusion or glucose uptake, has gained the status of an established finding in the medical literature on schizophrenia. Many relevant studies, however, have potential sources of bias, such as small subject numbers, or unreliable performance of activation tasks by the patients during the scanning procedure. Seventy patients with non-affective and non-organic psychoses were recruited--most qualifying for DSM III-R schizophrenia or schizophreniform psychosis (n = 60)--together with 20 healthy volunteers. They underwent single photon emission computed tomography with 99mTc-exametazime, carried out at rest. Tracer uptake was normalised to the occipital cortex. Group differences in tracer uptake were predicted in anterior regions of interest (prefrontal cortex and mesial frontal/cingulate cortex). Actively psychotic (including schizophrenic) patients not taking any drugs showed increased uptake in the prefrontal cortex. Reduced tracer uptake occurred in the mesial frontal cortex of schizophrenic patients, particularly if they were taking drugs. Relatively increased prefrontal tracer uptake associated with relatively decreased mesial frontal uptake characterised the patients in comparison with the controls. Generalised hypofrontality is, therefore, not a feature of schizophrenic patients at rest whether taking drugs or not.

Adolescent↗
PubMed1995

The neuropsychiatric sequelae of mercury poisoning. The Mad Hatter's disease revisited.

BACKGROUND: The detailed effects of mercury poisoning on cognitive function, brain anatomy and regional brain function are largely unknown. We report the case of a 38-year-old man who was exposed to toxic levels of inorganic mercury. METHOD: Four years after exposure, the patient was assessed using magnetic resonance imaging (MRI), single-photon emission computerised tomography (SPECT) and detailed neuropsychological evaluation. RESULTS: The patient developed a myriad of physical and psychiatric complaints, including stomatitis, muscle spasm, tremor, skin rash and the psychiatric syndrome known as 'erythism' (Mad Hatter's disease). Neuropsychological evaluation revealed marked and significant deficits of attention concentration, particularly when under time pressure. The MRI scan was unremarkable; however, SPECT revealed hypermetabolism of the posterior cingulate CONCLUSIONS: Mercury poisoning appeared to result in a dysregulation of posterior cingulate cortex, which was associated with attention/concentration deficits and marked anxiety/agitation.

Adult↗
PubMed1995

Magnetic resonance imaging and single photon emission tomography in treatment-responsive and treatment-resistant schizophrenia.

BACKGROUND: Patients with schizophrenia differ from controls in several measures of brain structure and function, but it is uncertain how these relate to clinical features of the illness. We dichotomised patient groups by treatment response to test the hypothesis that treatment-resistant patients exhibit more marked biological abnormalities than treatment-responsive patients. METHOD: Twenty treatment-responsive and 20 treatment-resistant patients with schizophrenia, matched for sex, age, and illness duration, were compared by magnetic resonance imaging, single photon emission tomography, and detailed neuropsychological assessment. RESULTS: Brain-imaging variables were not statistically related to treatment response, although poorly responsive patients had lower volumes of most brain structures. Several highly significant differences emerged between patient groups on neuropsychological testing. Episodic memory functioning distinguished patient groups even after we controlled for global cognitive impairment. CONCLUSIONS: Cerebral structure and blood flow have a limited effect on treatment response in schizophrenia, but long-term episodic memory impairment is associated with, and may predict, poor prognosis.

Activities of Daily Living↗
PubMed1995

Further evidence that reading ability is not preserved in Alzheimer's disease.

BACKGROUND: Pre-morbid intelligence level is routinely assessed in Alzheimer's disease using the National Adult Reading Test (NART). This practice is based on the assumption that pronunciation of irregular words remains unaffected by the disease process. Recent reports have suggested that reading ability may become compromised in moderately demented subjects. METHOD: Sixty-eight probably Alzheimer patients were classified into stages of severity (minimal, mild and moderate) using the Mini-Mental State Examination (MMSE). NART and demographic equations were used to estimate pre-morbid ability. RESULTS: A significant correlation emerged between dementia severity and reading ability, NART v. MMSE scores, r = 0.46, P < 0.01. When the total sample was subdivided into moderate, mild and minimal subgroups, significant between-group differences emerged, despite the groups being well matched for age, sex, and years of full-time education. Pre-morbid IQ, as estimated by demographic regression equations, did not correlate with dementia severity. CONCLUSION: NART performance is compromised in moderate Alzheimer disease, and the measure provides a serious underestimate of pre-morbid IQ in patients with an MMSE of 13 or less.

Aged↗
PubMed1994

Regional cerebral blood flow in IDDM patients: effects of diabetes and of recurrent severe hypoglycaemia.

Chronic hyperglycaemia and recurrent severe hypoglycaemia have both been implicated as causing cerebral damage in patients with diabetes. Although cognitive dysfunction and intellectual impairment have been demonstrated in patients with recurrent severe hypoglycaemia, structural correlates have not been described, and it is not known whether specific functional changes occur in the brains of affected patients. Regional cerebral blood flow was estimated by SPECT with 99mTechnetium Exametazime in 20 patients with IDDM. Ten patients had never experienced severe hypoglycaemia and 10 had a history of recurrent severe hypoglycaemia. Patient results were compared with 20 age- and sex-matched healthy volunteers. We observed differences between the two patient groups and the control group. Tracer uptake was greater in diabetic patients in the superior pre-frontal cortex. This effect was particularly pronounced in the group who had a history of previous severe hypoglycaemia. Patients with a history of recurrent hypoglycaemia also had a relative reduction in tracer uptake to the calcarine cortex. This suggests an alteration in the pattern of baseline regional cerebral blood flow in diabetic patients with frontal excess and relative posterior reduction in cerebral blood flow.

Adult↗
PubMed1994

Effects of glucocorticoids on 5-HT1A presynaptic function in the mouse.

8-OH-DPAT, a selective 5-HT1A agonist, produced a hypothermic response in mice at a dosage of 0.5 mg/kg. Administration of corticosterone-21-acetate (0.5, 5 and 50 mg/kg, daily for 3 and 10 days) produced a dose-dependent attenuation of this hypothermic response in mice. When all controls and corticosterone treated mice were retested, 14 days after initial testing, they did not differ in the hypothermic responses induced by 8-OH-DPAT. Mice treated with aldosterone (50 mg/kg), dexamethasone (50 mg/kg) and the specific type 2 corticosteroid receptor agonist, 11b,17b-dihydroxy-21-methyl-17a-pregna-1,4,6-trien-20-yn+ ++-3-one (RU26988, 30 mg/kg) for 10 days, did not differ from vehicle treated controls in the hypothermic response to 8-OH-DPAT. Mice administered corticosterone-21-acetate (30 mg/kg, daily) for 10 days displayed a motor behavioural syndrome, which was not seen in controls, when injected with 5-hydroxytryptophan (5-HTP, 100 mg/kg) 15 min after the injection of carbidopa (25 mg/kg). This was significantly decreased by pretreatment with the 5-HT1A receptor antagonist 1-(2-methoxyphenyl)-4-(4-phthalimidobutyl)-piperazine (NAN-190 5 mg/kg, 30 min prior to administration of carbidopa). Taken together, this evidence is compatible with a specific corticosterone induced facilitation of 5-HT release due to attenuation of inhibitory 5-HT1A autoreceptor function.

5-Hydroxytryptophan↗
PubMed1994

Effects of fluvoxamine treatment on cognitive functioning in the alcoholic Korsakoff syndrome.

Eight patients suffering from the alcoholic Korsakoff syndrome (AKS) were entered in a double-blind cross-over trial of fluvoxamine 200 mg per day for 4 weeks versus matched placebo for 4 weeks. At the end of each phase, patients were assessed using a detailed neuropsychological test battery. Verbal fluency performance was significantly impaired following fluvoxamine treatment. No significant differences emerged on any of the other cognitive test measures when fluvoxamine was compared with placebo. However, two of the patients developed a major depressive episode while receiving fluvoxamine.

Affect↗
PubMed1994

Oral D-fenfluramine and neuroendocrine challenge: problems with the 30 mg dose in men.

Ten healthy male volunteers of normal weight received 30 mg of D-fenfluramine, a putative selective releaser of 5-hydroxytryptamine (5-HT), and placebo by mouth in balanced order at a 1 week interval after a light breakfast. Blood was taken for estimation of plasma cortisol and prolactin, and the patients completed self rating scales for stress and arousal and rated themselves on visual analogue scales for mood, hunger and alertness at appropriate time points from 30 min before to 300 min after drug/placebo ingestion. There were no statistically discernible effects of D-fenfluramine on either hormone measures or subjective ratings. The failure to find effects may be due to a too low dose of D-fenfluramine and/or a lower sensitivity to the drug in men compared with women. More information is required on the dose/response relationship and drug absorption especially after food. However, the findings cast doubt on results already obtained employing this dose of the drug in studies that have included male subjects. Furthermore, the interpretation of earlier studies with D,L-fenfluramine at a dose of 60 mg is also made more uncertain by the failure to confirm that the more selective D-isomer produces equivalent effects.

Administration, Oral↗
PubMed1994

Diurnal variation of mood and neuropsychological function in major depression with melancholia.

20 DSM-III-R melancholics with clinically evident diurnal symptoms and 20 controls were assessed with a battery of neuropsychological tests, a test of maximum voluntary hand-grip, and neuroendocrine measures of hypothalamic-pituitary-adrenal axis function morning and evening in a 24-h period, using a balanced design. The morning pattern of neuropsychological impairment in the melancholics was comprehensive, affecting attention and concentration/working memory, episodic memory, reaction time and, strikingly, the speed of simultaneous match to sample, which was performed more slowly than the version of the task delayed to 0 or 4 s. The melancholics were significantly weaker than controls, on a measure of maximal voluntary contraction. Significantly improved neuropsychological function was seen in the melancholic patients in the evening, in line with diurnal improvement in mood; there was also a large increase in strength. Slowing on the digit symbol substitution test, the simultaneous match to sample task, total errors on the match to sample and hand-grip remained impaired in the evening compared to controls; other neuropsychological measures were no longer statistically different from control values which were often worsened. Neuroendocrine measures showed significantly raised levels of cortisol and ACTH morning and evening in the melancholics. Morning cortisol in the melancholics correlated with the diurnal improvement in neuropsychological functioning. The results have implications for the timing of neuropsychological assessment in major depression. Indices of neuropsychological and motor function may be as reliable quantitative estimates of illness severity as subjective estimates of mood.

Adrenocorticotropic Hormone↗
PubMed1994

Short-term effects of electroconvulsive treatment on the uptake of 99mTc-exametazime into brain in major depression shown with single photon emission tomography.

Fifteen patients with major depression who were being treated with bilateral electroconvulsive treatment (ECT) were investigated before and 45 min after a single ECT using split-dose Single Photon Emission Tomography (SPET or SPECT) with 99mTc-Exametazime. All patients suffered from unipolar depressive illness and were rated on the Newcastle scale and with the 17-item Hamilton scale. They completed tests of orientation and verbal memory on the day of ECT. For comparison, verbal memory was also tested on the preceding day. The uptake of 99mTc-Exametazime was expressed relative to calcarine/occipital cortex. Significant decreases in tracer uptake were confined to the inferior anterior cingulate cortex. The changes were correlated with the severity of depressive symptoms and more weakly with decrements of memory function produced by ECT; there was no significant correlation with stimulus intensity or electroencephalographic measures of seizure duration.

Aged↗
PubMed1994

PASAT performance and the pattern of uptake of 99mTc-exametazime in brain estimated with single photon emission tomography.

The effect of the paced auditory serial addition test (PASAT) on the regional uptake of 99mTc-exametazime was determined by single photon emission computed tomography. Twenty insulin-treated diabetic outpatients were scanned at rest and during the performance of the PASAT task using split-dose injection of tracer. When resting and activation scans were compared there were significant decreases in tracer uptake in the right anterior cingulate and left posterior cingulate areas during PASAT activation. The findings are compared with previous studies which had implicated the anterior cingulate area in the mechanisms of attention in humans and other animals. The potentially confounding role of anxiety during attentional tasks is discussed.

Adult↗
PubMed1994

Clonidine infusion increases uptake of 99mTc-Exametazime in anterior cingulate cortex in Korsakoff's psychosis.

The effects upon regional brain function of infusing either saline or clonidine (1.5 microgram/kg) has been examined in 18 patients with alcoholic Korsakoff's psychosis using 99mTc-hexamethylpropyleneamineoxime (99mTc-HMPAO or 99mTc-Exametazime) and Single Photon Emission Tomography (SPET or SPECT). The hypothesis tested was that frontal lobe function would be increased by adrenoceptor stimulation. This was confirmed by an increase in the uptake of 99mTc-Exametazime into anterior cingulate regions of the frontal lobes. Patients were scanned before and after saline or clonidine infusion during performance of a verbal fluency task. There was a significantly increased performance of verbal fluency in patients given clonidine. This effect was variable and could not be unequivocably distinguished from increases in performance in the saline treated group. Nevertheless, the increase in neuropsychological performance was also correlated with increased function in left dorsolateral frontal cortex within the clonidine treated group. An exploratory examination of other brain areas suggested that relative increases in posterior cingulate cortex and changes in the symmetry of function within the thalamus may also be produced by acute infusion of clonidine in Korsakoff patients. The findings support the idea that adrenergic mechanisms may modulate cognitive performance by actions on attentional systems within the brain. These appear to be located primarily within limbic cortex. It is, of course, notable that this can occur in patients with profound and disabling amnesia.

Adult↗
PubMed1994

Correlation of regional cerebral blood flow equivalents measured by single photon emission computerized tomography with P300 latency and eye movement abnormality in schizophrenia.

Single photon emission tomography with the intravenous blood flow marker 99mTc-exametazime was carried out in 14 acutely ill drug-free schizophrenic patients from whom P300 event-related potential, smooth eye pursuit eye tracking and verbal fluency were measured within a few days of scanning. Smooth pursuit eye movement abnormality correlated significantly with abnormal tracer uptake in superior pre-frontal cortex on the right and left and inferior pre-frontal cortex on the left. Abnormal eye movement was also associated with higher tracer uptake in left anterior cingulate and left posterior cingulate. P300 latency was significantly correlated with higher tracer uptake in left superior pre-frontal and left parietal regions. Verbal fluency performance was negatively correlated with tracer uptake in left frontal region. Eye tracking abnormality in schizophrenia is associated with bilateral frontal lobe disturbance and P300 latency increase with left-sided frontal and temporoparietal dysfunction. There was, however, a significant inverse relation between eye tracking abnormalities and abnormal perfusion in the left anterior cingulate region.

Adult↗
PubMed1994

Uptake of 99mTc-exametazime shown by single photon emission computerized tomography in obsessive-compulsive disorder compared with major depression and normal controls.

Twelve patients with obsessive-compulsive disorder (OCD) were investigated at rest using single photon emission computerized tomography with 99mTc-exametazime. The uptake of 99mTc-exametazime was expressed relative to calcarine/occipital cortex. Patients were matched for drug treatment with 12 patients with a major depressive episode and the patient groups were compared with a control group. Significant bilateral decreases in tracer uptake were confined to basal ganglia in the OCD group. There was a paradoxical positive correlation between anxiety ratings and tracer uptake to basal ganglia in the OCD group. The findings confirm that the functional topography of OCD implicates altered function in the basal ganglia.

Adult↗
PubMed1994

The differentiation of major depression from dementia of the Alzheimer type using within-subject neuropsychological discrepancy analysis.

The method of comparing premorbid versus current intellectual ability has become established clinical practice in the differential diagnosis of dementia versus depression. Recently, Schlosser & Ivison (1989) suggested that the comparison of premorbid ability versus current memory function may offer a more sensitive method of assessing early dementia. In the present study, a variety of within-subject discrepancy analyses comparing premorbid estimates with current measures of memory and intellectual functioning were compared across three groups: patients with dementia of the Alzheimer type, patients with major depression and healthy controls. The results revealed that, while mean group differences were easily demonstrated, the overlap between Alzheimer and depressed patients was large. It is concluded that none of the simple neuropsychological discrepancy analyses examined in the present study can be recommended for use in clinical practice for the differential diagnosis of dementia from major depression.

Aged↗
PubMed1994

Single photon emission computed tomography in long-term survivors of adult brain tumours.

Sixteen patients with primary brain tumours were examined on average eight years after treatment with surgery or whole brain irradiation using standard clinical assessment, CT, a neuropsychological test battery, and single photon emission CT (SPECT) with 99mTc-exametazime. Seventeen lesions were discovered on inspection of SPECT images, 11 with x-ray CT. Quantitative assessment of tracer uptake compared with 16 matched healthy volunteers was consistent with the presence of lesions. Measurement of uptake in brain regions of the hemisphere not containing the primary tumour still showed significant reductions in patients. This may be due to remote direct effects of the tumour or, more likely, to the whole brain irradiation received. Psychometric performance on most tests was significantly impaired in the patient group and was correlated with abnormalities of tracer uptake to relevant brain regions.

Adult↗
PubMed1993

Single-photon emission computed tomography with 99mTc-exametazime in unmedicated schizophrenic patients.

We examined 20 actively psychotic unmedicated schizophrenic patients and 20 matched control subjects by using single-photon emission, computed tomography (SPECT) with 99mtechnetium-exametazime. Patients showed a hyperfrontal pattern of tracer uptake with significant relative increases in superior prefrontal cortex. This abnormality was less pronounced in patients with higher symptom scores for psychomotor poverty. In addition, patients showed associations between certain schizophrenic syndrome scores, such as psychomotor poverty, disorganization, and reality distortion, and tracer uptake to a number of cortical and subcortical brain regions. This syndrome-related pattern of tracer uptake was, at least in part, consistent with similar associations previously reported in chronically medicated schizophrenic patients. SPECT therefore provides a readily available method to examine the relationship between symptom pattern and regional brain metabolism in psychotic patients. Any observed patterns of association will depend on the current mental and medication status of the patients examined.

Adult↗