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S Galderisi

Publications and source records attributed to S Galderisi.

At least 19 recordsLinked to original sources
PubMed2005

Decrease of functional coupling between left and right auditory cortices during dichotic listening: an electroencephalography study.

The present study focused on functional coupling between human bilateral auditory cortices and on possible influence of right over left auditory cortex during dichotic listening of complex non-verbal tones having near (competing) compared with distant non-competing fundamental frequencies. It was hypothesized that dichotic stimulation with competing tones would induce a decline of functional coupling between the two auditory cortices, as revealed by a decrease of electroencephalography coherence and an increase of directed transfer function from right (specialized for the present stimulus material) to left auditory cortex. Electroencephalograph was recorded from T3 and T4 scalp sites, overlying respectively left and right auditory cortices, and from Cz scalp site (vertex) for control purposes. Event-related coherence between T3 and T4 scalp sites was significantly lower for all electroencephalography bands of interest during dichotic listening of competing than non-competing tone pairs. This was a specific effect, since event-related coherence did not differ in a monotic control condition. Furthermore, event-related coherence between T3 and Cz and between T4 and Cz scalp sites showed no significant effects. Conversely, the directed transfer function results showed negligible influence at group level of right over left auditory cortex during dichotic listening. These results suggest a decrease of functional coupling between bilateral auditory cortices during competing dichotic stimuli as a possible neural substrate for the lateralization of auditory stimuli during dichotic listening.

Acoustic Stimulation↗
PubMed2002

Clinical applications of pharmaco-EEG in psychiatry: the prediction of response to treatment with antipsychotics.

The prediction of response to psychotropic drugs is of enormous interest in psychiatry, since absent or incomplete response to treatment may extend hospitalization time, increase direct and indirect costs of illness and, according to the so-called neurotoxicity hypothesis, worsen the illness prognosis. In the first part of the presentation, basic assumptions of pharmaco-EEG relevant to the topic of the prediction of clinical response to antipsychotic treatment are summarized. The first step in the approach to this topic is the characterization of the quantitative EEG (QEEG) profile of the investigated drug. This is generally accomplished by assessing QEEG changes induced by a single dose of the same drug to groups of healthy subjects (test dose procedure). The prediction of patient responsiveness to a specific drug is based on the assessment of the similarity of their QEEG profile to the drug characteristic profile. In the second part of the presentation, main findings concerning QEEG changes induced by the acute administration of standard neuroleptics or novel antipsychotics in healthy subjects and in patients with schizophrenia are described. In the conclusion, achievements, limitations and future perspectives of the research field are outlined.

Antipsychotic Agents↗
PubMed2001

Brain electrical microstates in subjects with panic disorder.

Brain electrical microstates represent spatial configurations of scalp recorded brain electrical activity and are considered to be the basic elements of stepwise processing of information in the brain. In the present study, the hypothesis of a temporo-limbic dysfunction in panic disorder (PD) was tested by investigating the topographic descriptors of brain microstates, in particular the one corresponding to the Late Positive Complex (LPC), an event-related potential (ERP) component with generators in these regions. ERPs were recorded in PD patients and matched healthy subjects during a target detection task, in a central (CC) and a lateral condition (LC). In the CC, a leftward shift of the LPC microstate positive centroid was observed in the patients with PD versus the healthy control subjects. In the LC, the topographic descriptor of the first microstate showed a rightward shift, while those of both the second and the fourth microstate, corresponding to the LPC, revealed a leftward shift in the PD patients versus the healthy control subjects. These findings indicate an overactivation of the right hemisphere networks involved in early visual processing and a hypoactivation of the right hemisphere circuits involved in LPC generators in PD. In line with this interpretation, the abnormal topography of the LPC microstate, observed in the CC, was associated with a worse performance on a test exploring right temporo-hippocampal functioning. Topographical abnormalities found for the LPC microstate in the LC were associated with a higher number of panic attacks, suggesting a pathogenetic role of the right temporo-hippocampal dysfunction in PD.

Adult↗
PubMed2000

Qualitative MRI findings in patients with schizophrenia: a controlled study.

A variety of brain structural abnormalities, which can be identified only by qualitative methods, have been shown to correlate with clinical presentation and course of schizophrenia. In the present study, MRI scans of 122 patients with DSM-IV schizophrenia and 81 non-psychiatric controls were evaluated. Among males, the frequency of CNS developmental abnormalities (CDAs) was higher in patients than in controls. Lateral ventricular enlargement (LVE) was more frequent in patients than in controls; when subjects were grouped in three age classes, LVE was more frequent in patients than in controls in the youngest and the oldest age group. Patients with LVE or third VE were older than those without these abnormalities. Schizophrenic patients with LVE or cortical atrophy (CA) had a longer duration of illness than those without these abnormalities. Both patients with LVE and those with third VE had a poorer outcome than those without these abnormalities. CDA findings add to the evidence of a higher frequency of neurodevelopmental abnormalities in male schizophrenic patients. Results concerning LVE suggest that both developmental and degenerative processes underlie this abnormality. The association of LVE and third VE with a poor outcome indicates that qualitative MRI evaluation might be of clinical relevance.

Adolescent↗
PubMed1999

'Simple schizophrenia': a controlled MRI and clinical/neuropsychological study.

The present study explored the frequency of neuromorphological, neurological and neuropsychological abnormalities in 13 patients with an ICD-8/9 diagnosis of simple schizophrenia, also fulfilling DSM-IV criteria for 'simple deteriorative disorder', and in 13 matched patients with an ICD-8/9 diagnosis of a subtype of schizophrenia other than simple schizophrenia, fulfilling DSM-IV criteria for schizophrenia. The frequency of neuromorphological abnormalities in the two patient groups was also compared with that observed in 13 neurological control subjects. Both patients with simple schizophrenia and those with other schizophrenia subtypes showed a higher frequency of brain developmental abnormalities and greater ventricular and subarachnoid space volumes than controls. There was no significant difference between the two groups of patients with respect to neuromorphological variables. Two patients with simple schizophrenia (vs. none of those with other schizophrenia subtypes) had gross brain abnormalities; they were the most deteriorated subjects in the whole sample. Patients with simple schizophrenia, as compared to those with other schizophrenia subtypes, presented a higher frequency of soft neurological signs and a greater impairment of social relationships.

Adult↗
PubMed1999

Hemispheric asymmetry and psychopathological dimensions in drug-free patients with schizophrenia.

Several neuropsychological models of schizophrenia have regarded the syndrome as a disorder of the left hemisphere. However, discrepant experimental findings have been reported. It has been proposed that the different psychopathological dimensions of the syndrome are associated with distinct patterns of hemispheric imbalance. The present study was aimed at exploring relationships of psychopathological dimensions of schizophrenia with fronto- and temporo-hippocampal functioning of either hemisphere in 42 drug-free patients with a DSM-III-R diagnosis of schizophrenia. For the negative dimension, an inverse correlation with the performance on a verbal conditional associative task was found, consistent with the presence of a left fronto-hippocampal impairment in this dimension. As to the positive dimension, our results showed a direct correlation with perseveration on a verbal self-ordered pointing task, suggesting a hyperactivation of the left-hemisphere in this dimension. The disorganisation was found to be associated with a faster execution of a spatial memory task, probably reflecting increased perceptual priming and a right temporo-hippocampal disinhibition.

Adolescent↗
PubMed1996

Multilead quantitative EEG profile of clozapine in resting and vigilance-controlled conditions.

Clozapine is the prototype of a new class of drugs, referred to as 'atypical antipsychotics'. As a matter of fact, the antipsychotic activity of the drug was not predicted by the first studies with quantitative electroencephalography (QEEG), which actually reported an antidepressant pattern. All previous QEEG studies carried out in healthy subjects used a maximum of four leads, exploring only the posterior quadrants of the scalp. The present article reports findings of a multilead QEEG study carried out in 16 healthy men under resting and vigilance-controlled conditions. Increases in slow (delta, theta, and alpha1) and decreases in fast (alpha2 and beta) activities were found, corresponding to changes described for chlorpromazine-type antipsychotics. These results are compared with those of earlier studies. It is suggested that changes in the beta frequency range vary across subjects, whereas changes in slow and alpha activity are more consistent and critical for defining the QEEG profile of the drug.

Adult↗
PubMed1996

Influence of moclobemide on cognitive functions of nine depressed patients: pilot trial with neurophysiological and neuropsychological indices.

Quantitative electroencephalogram (QEEG) changes induced by the acute administration of moclobemide (200 mg) in patients with major depression include a transient increase in theta-activity, a slight augmentation of alpha-activity and a sustained increase in beta-activity. This QEEG profile distinguishes moclobemide from sedative antidepressants. A 42-day treatment with 400 mg/day of the drug produces a significant decrease in the late positive-complex peak latency of the event-related potentials, suggesting a positive effect on attention and cognitive functions.

Adult↗
PubMed1995

Neuropsychological slowness in obsessive-compulsive patients. Is it confined to tests involving the fronto-subcortical systems?

BACKGROUND: Although it is acknowledged that obsessive-compulsive (OC) patients may be slower than healthy controls in performing neuropsychological tests, speed has usually been treated as a confounding variable. It is possible, however, that the slower performance of OC patients is itself the result of a dysfunction of specific neural circuits (in particular of fronto-subcortical systems). METHOD: A neuropsychological battery including tests sensitive to fronto- and temporo-subcortical dysfunction was administered to a group of OC patients and a group of healthy controls. Each test provided independent indices of accuracy and speed. RESULTS: OC patients were significantly slower than controls only when performing tasks involving the fronto-subcortical systems, whereas they did not differ from controls with respect to accuracy indices. CONCLUSION: It may be that neuropsychological slowness of OC patients is not merely an epiphenomenon of meticulous concern for correct test execution or intrusion of obsessive thoughts, but reflects the dysfunction of fronto-subcortical systems.

Adolescent↗
PubMed1994

QEEG alpha 1 changes after a single dose of high-potency neuroleptics as a predictor of short-term response to treatment in schizophrenic patients.

Baseline quantitative electroencephalographic (QEEG) characteristics and their changes after a single test dose of either haloperidol or clopenthixol were investigated in a group of 29 schizophrenics as possible predictors of short-term response to those drugs. On baseline QEEG assessment, responders (R) to subsequent treatment showed fewer slow and more fast activities than nonresponders (NR). A large overlap between R and NR with respect to these measures was observed, however, revealing their practical inadequacy to predict short-term response in individual patients. On the contrary, changes in alpha 1, observed 6 hr after the administration of a single test dose of either haloperidol or clopenthixol, discriminated to a very large extent between R and NR, correctly identifying 17 out of 18 R and 8 out of 10 NR. The QEEG test dose procedure might be used in the selection of the most appropriate antipsychotic drug for individual schizophrenic patients.

Adolescent↗
PubMed1993

Evaluation of two new neuropsychological tests designed to minimize cultural bias in the assessment of HIV-1 seropositive persons: a WHO study.

In the course of the preparatory work for the WHO cross-cultural study on the neuropsychiatric aspects of HIV-I infection, two new neuropsychological tests (the WHO/UCLA Auditory Verbal Learning Test and the Color Trails 1 & 2) were developed. The evaluation of these tests was performed at four sites, two in developed and two in developing countries. The data obtained suggest that the tests are more culture fair than others currently used to assess the same functional domains, that they are sensitive to HIV-1-associated cognitive impairment, and that this sensitivity "holds" across different cultures.

Journal Article↗
PubMed1992

Computerized EEG topography findings in schizophrenic patients before and after haloperidol treatment.

An increase of delta and fast beta activity in schizophrenic patients when compared with normal controls has been consistently reported. Topography of these abnormalities, in particular a possible frontal localization of delta, and their relationship to drug treatment and clinical status are still debated. In order to assess these issues, a multilead CEEG investigation was carried out in a group of 20 DSM-III-R schizophrenics, both before and after haloperidol treatment. All findings are described in terms of amplitude and relative power. Drug-free schizophrenics, when compared with a group of normal controls, showed a generalized increase of delta and fast beta, and a decrease of alpha 2 relative power. After acute treatment, patients showed a significant decrease of delta, and an increase of theta 2, beta 1, and beta 2. After 28 days of haloperidol treatment, similar changes were observed for delta, together with an increase of alpha 1, and a decrease of fast beta.

Adult↗
PubMed1991

Lateralization patterns of event-related potential and performance indices in schizophrenia: relationship to clinical state and neuroleptic treatment.

In a previous study we assessed lateralization patterns of verbal stimuli processing, by means of behavioural and neurophysiological measures, in a sample of drug-free schizophrenics and one of normal controls. The main findings obtained were the following: (1) a right visual field (RVF) advantage on reaction time (RT) and late positive complex (LPC) peak of the ERPs in normal subjects but not in schizophrenics; (2) a left visual field (LVF) significant advantage on P360 and slow wave (SW) amplitude in schizophrenics but not in controls; (3) a significantly longer RT and smaller P360 and SW for RVF stimuli in schizophrenics as compared to normals; (4) a significant contralateral effect of visual field on N180 at both the left and the right parietal site in normal controls and only at the right parietal site in schizophrenics. As a further step of this investigation we re-tested 9 schizophrenics after 28 days of haloperidol treatment. The post-treatment lateralization pattern of verbal stimuli processing was characterized by a RVF advantage on LPC peak amplitude and no visual field effect on P360 and SW, resembling the normal group pattern. Moreover, the N180 amplitude was found to be reduced. Relationships between lateralization pattern and clinical picture changes induced by haloperidol treatment are discussed.

Adult↗
PubMed1991

CEEG mapping in drug-free schizophrenics. Differences from healthy subjects and changes induced by haloperidol treatment.

A topographic CEEG investigation was carried out in 20 drug-free, DSM-IIIR diagnosed schizophrenics and in a group of matched healthy controls. The effects of acute and chronic haloperidol treatment were then assessed in the patient group. On the baseline recording, schizophrenics showed a widespread increase in delta, theta 1 and beta 3 amplitude. Acute haloperidol administration produced a decrease in delta and an increase in slow beta amplitude. After 28 days of treatment, delta and fast beta were reduced while theta 2 and alpha 1 were increased. CEEG abnormalities in schizophrenic subjects appear, therefore, to be reduced by chronic neuroleptic treatment.

Adult↗
PubMed1990

Factors associated with increased noradrenaline levels in schizophrenic patients.

1. CSF NA levels were determined in a sample of DSM III-diagnosed schizophrenics and in a non-psychiatric control group. Schizophrenics with NA levels above and below the median were compared with respect to several clinical, historical, neuropsychological and biological variables. 2. Mean CSF NA levels were significantly higher in schizophrenics than in controls. 3. Schizophrenics with high CSF NA levels, as compared to those with low levels, had significantly higher scores on the CPRS subscale for positive symptoms. Moreover, in the former subgroup, C-EEG alpha relative activity was significantly lower and C-EEG beta relative activity was significantly higher in frontal and central leads. Two of the three patients who had been never treated with neuroleptics, and three of the six patients who had been neuroleptic-free for more than four weeks had high CSF NA levels. 4. These data support the relationship between increased CSF NA levels and the condition of overarousal of the schizophrenic patients, and suggest that prior neuroleptic treatment is not a major determinant of high CSF NA concentration in schizophrenics.

Adolescent↗
PubMed1990

C-EEG brain mapping in DSM-III schizophrenics after acute and chronic haloperidol treatment.

A multi-lead C-EEG investigation was carried out, in order to evaluate changes induced by acute and chronic treatment with haloperidol in DSM-III-R schizophrenics. After the acute treatment the main C-EEG changes were (1) a significant decrease of delta relative power (RP) over all the explored leads and of theta 1 over the occipital leads; (2) an increase in alpha 2 and beta 2 RP, as well as a decrease of beta 3 RP confined to the anterior temporal leads (T3, T4). During chronic treatment, C-EEG changes observed were (1) a significant decrease of delta RP and an increase of theta 1 RP; (2) an increase of alpha 1 and alpha 2 RP; (3) a significant decrease of beta 1, beta 2 and beta 3.

Adult↗