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Biomedical subjects

S Scarone

Publications and source records attributed to S Scarone.

At least 19 recordsLinked to original sources
PubMed2004

Theory of Mind in schizophrenia: first person vs third person perspective.

Patients suffering from schizophrenia have an impaired meta-representation also known as Theory of Mind (ToM). Moreover, the presence of delusions or other positive symptoms of schizophrenia has been correlated to poor ToM performances. Lack of insight is a common symptom of schizophrenia and can be considered a critical manifestation of impaired ToM abilities. In particular, the present study addresses the role of perspective ToM ability in schizophrenic patients. Thirty severely delusional schizophrenic patients completely lack insight when interviewed about their delusions. Seven subsequently gain insight about their mental state when perspective is shifted from the first person to third person. These data suggest that in some delusional schizophrenic patients, it may be possible to gain access to and modify their mental states.

Adult↗
PubMed2003

Executive dysfunction and avoidant personality trait in myotonic dystrophy type 1 (DM-1) and in proximal myotonic myopathy (PROMM/DM-2).

A previous study in proximal myotonic myopathy (PROMM/DM-2) and myotonic dystrophy type 1 (DM-1) using brain positron emission tomography demonstrated a reduced cerebral blood flow in the frontal and temporal regions associated with cognitive impairment. The objective was to investigate further cognitive and behavioural aspects in a new series of patients with DM-1 and PROMM/DM-2. Nineteen patients with genetically determined PROMM/DM-2 and 21 patients with moderately severe DM-1 underwent neuropsychological testing and neuropsychiatric interviews. DM-1 and PROMM/DM-2 patients had significantly lower scores on tests of frontal lobe function compared to controls. Neuropsychiatric interviews demonstrated an avoidant trait personality disorder in both patient groups. Brain single photon emission computed tomography showed frontal and parieto-occipital hypoperfusion. The results suggest that there is a specific cognitive and behavioural profile in PROMM/DM-2 and in DM-1, and that this profile is associated with hypoperfusion in frontal and parieto-occipital regions of the brain.

Adult↗
PubMed1999

Clozapine lacks previous clinical efficacy when restarted after a period of discontinuation: a case series.

No data are available in the literature about clozapine clinical efficacy when the drug is administered to schizophrenic patients who relapsed after discontinuation of long-term clozapine treatment and who had previously been responsive to the drug. In this study, three chronic schizophrenic patients are presented, who, in spite of a good clinical efficacy, decided to stop long-term clozapine treatment. Soon after their relapse they were again treated with clozapine: follow-up of these patients showed that clozapine partially lost its clinical efficacy since all three patients got worse compared with their initial clinical response.

Adult↗
PubMed1999

An artificial neural network that uses eye-tracking performance to identify patients with schizophrenia.

Several researchers have underscored the importance of precise characterization of eye-tracking dysfunction (ETD) in patients with schizophrenia. This biological trait appears to be useful in estimating the probability of genetic recombination in an individual, so it may be helpful in linkage studies. This article describes a nonlinear computational model for using ETD to identify schizophrenia. A back-propagation neural network (BPNN) was used to classify schizophrenia patients and normal control subjects on the basis of their eye-tracking performance. Better classification results were obtained with BPNN than with a linear computational model (discriminant analysis): a priori predictions were approximately 80 percent correct. These results suggest, first, that eye-tracking patterns can be useful in distinguishing patients with schizophrenia from a normal comparison group with an accuracy of approximately 80 percent. Second, parallel distributed processing networks are able to detect higher order nonlinear relationships among predictor quantitative measurements of eye-tracking performance.

Adult↗
PubMed1999

Spatial working memory in asymptomatic HIV-infected subjects.

Many clinical and research findings converge to indicate that frontal lobe, basal ganglia, and related neuronal connections are primarily involved in human immunodeficiency virus (HIV) infection; frontal lobe, mainly the prefrontal cortex, has a specialized role in working memory processes. This study focused on neuropsychological evaluation of the spatial component of working memory in a sample of 34 asymptomatic HIV-infected subjects as compared with 34 age- and sex-matched seronegative control subjects. A computer-administered test assessing spatial working memory was used for the neuropsychological evaluation. The findings did not show any spatial working memory impairment during the asymptomatic phase of HIV infection.

Adult↗
PubMed1998

Frontal lobe dysfunction in obsessive-compulsive disorder and major depression: a clinical-neuropsychological study.

Neuropsychological findings support a hypothesized relationship between obsessive-compulsive disorder (OCD) and the frontal lobe. The aim of the present study was to compare findings of neuropsychological tests of frontal lobe function in 28 OCD patients and 29 patients with major depressive disorder (MDD), all diagnosed according to DSM III-R criteria. The patient groups were homogeneous for educational level, handedness, duration of illness, and sex distribution. All 57 subjects received a battery of tests sensitive to frontal lobe dysfunction as well as the Wechsler Memory Scale (WMS). Clinical symptomatology in the MDD and OCD groups was assessed with the Hamilton Rating Scale for Depression and the Yale-Brown Obsessive-Compulsive Scale, respectively. The only significant difference between the two diagnostic groups for any of the neuropsychological indices, with age as a covariate, was in the Object Alternation Test, in which OCD patients had a significantly higher number of perseverative responses. Test performances were not correlated with clinical symptomatology or severity of illness. Our preliminary results confirm the hypothesis that there is a selective impairment of orbito-frontal cortex in OCD and seem to exclude the existence of specific frontal lobe dysfunction in MDD, even though the two disorders show clinical similarities.

Adult↗
PubMed1998

Delusional disorder and eye tracking dysfunction: preliminary evidence of biological and clinical heterogeneity.

This study used eye tracking movement tests to examine the relationships between frontal field functions and clinical features. Smooth pursuit and voluntary saccadic eye movements were recorded and analyzed in 34 delusional disorder (DD) patients and in 40 normal subjects. The DD group differed significantly from the group of normal subjects in some eye tracking performances. As reported in our previous study (Gambini et al., 1993), DD patients showed abnormalities of voluntary saccadic eye movements. In this study, we also found abnormal smooth pursuit eye movements, indicating a cerebral dysfunction similar to those detected in schizophrenic patients. Moreover, normal smooth pursuit eye movement performance in DD patients was related to remitted depressive mood and probably to benefit from antipsychotic medications, thus supporting the idea of the biological and clinical heterogeneity of DD.

Adult↗
PubMed1998

Cytokines production in chronic schizophrenia patients with or without paranoid behaviour.

1. Several immunological abnormalities have been found in schizophrenia but their significance still remains largely unknown. In this study the authors analyzed mitogen-stimulated interleukin (IL)-2, Interferon gamma (IFN)-gamma and IL-10 (type 2 cytokine) production in a sample of 37 chronic schizophrenic patients as compared with a sample of 40 age and sex-matched controls with the aim to evaluate whether patients belonging to different diagnostic subtypes (i.e. paranoid patients vs non paranoid patients) could be immunologically different from each other. 2. The findings indicate that paranoid patients produce less IL-10 than the others and thus, from an immunological viewpoint, they are more similar to healthy controls. 3. Furthermore, neuroleptic medications were observed to differently affect IL-2 production; this preliminary finding might stimulate further studies aiming to get a link between different drug profile of action both in terms of clinical and receptorial profile and different immunological effects.

Adult↗
PubMed1997

The selective breakdown of frontal functions in patients with obsessive-compulsive disorder and in patients with schizophrenia: a double dissociation experimental finding.

In an our recent preliminary study, we reported the neuropsychological finding of a double dissociation in the frontal lobe functioning between 25 OCD patients and 25 schizophrenics. The first group performed normally in the Wisconsin Card Sorting Test (WCST), which is considered sensitive to Dorso-Lateral Prefrontal Cortex (DLPFC) dysfunctions and abnormally to the Object Alternation Test (OAT), which has been proposed as a tool sensitive to Orbito-Frontal Cortex (OFC); on the other hand, schizophrenics performed abnormally to the WCST and normally to the OAT. The present study, conducted on a new sample of 60 schizophrenic in-patients, 60 OCD in-patients and 30 normal subjects, matched according to age, educational level, handedness and duration of illness, confirms our preliminary data and it suggests a more selective impairment of OFC system in OCD and of DLPFC in schizophrenia. Moreover, schizophrenic patients with paranoid subtype showed worse WCST performance compared to non-paranoid subtype. Our results could open some interesting perspectives about the neuroanatomical systems involved in these two major psychiatric illnesses and so, about their pharmacological treatment, on the basis of the prominent catecholaminergic characterization of the DLPFC and, respectively, the cholinergic innervation of the OFC.

Adult↗
PubMed1997

Efficacy of paroxetine for the treatment of depression in the context of HIV infection.

Recent studies in the literature point out that HIV-infected subjects are affected by depression with a relatively high frequency. The aim of this study was to assess the efficacy and tolerability of paroxetine for the treatment of depression in the context of HIV infection. 15 HIV-infected subjects (10 patients with a major depressive episode and 5 patients with an adjustment disorder with depressed mood, according to the DSM IV diagnostic criteria) were administered paroxetine at a daily dosage of 20 mg. Depressive symptomatology was monitored by means of the Hamilton Rating Scale for Depression (HAM-D) at the time of enrollment and 2 weeks, 4 weeks, and 6 weeks later; at the same times adverse effects were recorded. 14 patients completed the study, and all of these recovered from depression; HAM-D mean scores significantly improved from baseline to final assessment, both when all subjects were considered (ANOVA for repeated measurements: p < or = 0.0001) and when only patients with a major depressive episode were included in the statistical analysis (ANOVA for repeated measurements: p < 0.0001). No significant adverse effects were recorded. Because of its efficacy and good tolerability paroxetine seems to be suitable for the treatment of depression in the context of HIV infection.

Adult↗
PubMed1997

A preliminary report of a strong genetic component for thought disorder in normals. A twin study.

Several authors have investigated the presence of thought disorder in psychiatric patients using different reliable methods. Under the hypothesis of a genetic predisposition to thought disorder, the degree and quality of thought disorder have also been studied in populations at a high risk for psychosis, in particular for schizophrenia. As a result, an increasing incidence of thought disorder was detected in relatives of schizophrenics. To account for the thought disorder also found in normal subjects, researchers propose that thought disorder exists in normal subjects on a continuum with schizophrenic patients. In the following report, we evaluated the inherited component of thought disorder in normal subjects, using a sample of 25 normal twin pairs, 16 monozygotic and 9 dizygotic twin pairs. We applied the Thought Disorder Index (TDI) to assess disordered thinking, genetic estimates were made with classical methods, controlling for environmental sources of variability where possible. Our findings suggest a strong additive genetic component for the global TDI rating variable, with a heritability estimate approaching 80-90%. New approaches in neuropsychology and neuropsychiatry-based on genetic methodologies should further define the cerebral physiology responsible for disordered thinking.

Adult↗
PubMed1996

Performance on the Wisconsin Card Sorting Test in schizophrenia: perseveration in clinical subtypes.

Results are reported from a neuropsychological investigation of a large group of schizophrenic patients (n = 141) and normal control subjects (n = 59) who performed the Wisconsin Card Sorting Test (WCST). The schizophrenic patients were divided into two DSM-III-R diagnostic subgroups: paranoid and nonparanoid schizophrenia. The performance of the WCST by schizophrenic patients was poor compared with that by normal control subjects; furthermore, paranoid patients made a higher number of perseverative errors than did nonparanoid patients. The deficit in WCST performance, which has been widely reported to characterize patients with schizophrenia, appears to be related to the clinical profile and neuropathological differences that contribute to the heterogeneity of the disorder.

Adult↗
PubMed1996

Temporal lobe electroencephalogram power modifications during olfactory stimulation in HIV-infected patients.

Evidence derived from studies concerning brain metabolism and brain electrical activity suggests that temporal lobe functioning is impaired in the course of HIV infection. To test the hypothesis of temporal lobe dysfunction in HIV infection, we utilized computerized electroencephalogram (EEG) analysis to evaluate temporal lobe EEG power modifications induced by olfactory stimulation in 10 HIV-infected patients as compared with 10 seronegative control subjects. Our findings show that HIV-infected patients respond to olfactory stimulation with an increase in temporal lobe slow electrical activity (theta EEG power), whereas control subjects show a decrease in the same activity. The theta EEG power increase during olfactory stimulation in HIV-infected patients can be interpreted as a paradoxical response of the deep temporal regions to specific procedures, supporting the hypothesis of temporal lobe dysfunction in HIV infection.

Adult↗
PubMed1996

EEG power modifications in obsessive-compulsive disorder during olfactory stimulation.

Temporal lobe electroencephalogram (EEG) activity was quantitatively analyzed in obsessive-compulsive disorder (OCD) when subjects are at rest and during a temporal lobe activating procedure, i.e., olfactory stimulation. At rest with eyes closed, delta-1 and alpha-2 power differences were evident in OCD patients as compared with normal controls. During olfactory stimulation, differences between patients and normal groups were detectable in the slower beta frequencies: Normal subjects showed a power increase, whereas OCD patients showed no modification or slight decrease. Our results support previous findings of temporal lobe EEG abnormalities in OCD patients with an abnormal pattern of response to a temporal lobe activating procedure.

Adult↗
PubMed1996

Abnormal pattern of platelet APP isoforms in Alzheimer disease and Down syndrome.

OBJECTIVE: To determine if changes in levels of amyloid precursor protein (APP) isoforms in periphery are associated with Alzheimer disease and Down syndrome. DESIGN: After subjects were grouped according to diagnosis, APP isoform levels in platelets were compared. SETTING: University medical center. SUBJECTS: Ten patients who fulfilled diagnostic criteria for probable Alzheimer disease, 22 healthy volunteers, and 7 elderly (mean age, 42.7 years) and 7 young (mean age, 19.0 years) patients with Down syndrome. MAIN OUTCOME MEASURES: The levels of APP isoforms were evaluated by means of Western blot analysis and immunostaining of whole platelets. RESULTS: The ratio between the 130- and the 106- to 110-kd APP isoforms was markedly lower in patients with Alzheimer disease and in elderly patients with Down syndrome than in control subjects. In young patients with Down syndrome, the ratio did not significantly differ from that in control subjects. CONCLUSIONS: A consistent alteration in platelet APP isoforms has been found in Alzheimer disease and Down syndrome. Further studies will determine whether this alteration could provide a peripheral biochemical marker of the disorder and whether it could intervene in the pathogenesis of Alzheimer disease.

Aged↗
PubMed1996

The Wisconsin Card Sorting Test (WCST) performance in normal subjects: a twin study.

The aim of this study was to evaluate the WCST, a task linked to the frontal (prefrontal) cortex, in normal twins to detect an inherited component of frontal lobe function. The WCST scores of 15 monozygotic (MZ) twin pairs, 9 dizygotic (DZ) twin pairs, and 15 unrelated control pairs were used to compute genetic estimates. No significant differences were detected between MZ, DZ and control groups intrapair correlation coefficients. No significant heritability estimates different by zero were computed. The frontal lobe function measured by WCST performance in normal twins does not seem to have a high degree of genetic component, and larger samples of twins are required to detect low genetic effects. The possible implications of such results about the genetic predisposition of frontal deficit in schizophrenia have been discussed.

Adult↗
PubMed1996

Structured psychiatric interview and ambulatory sleep monitoring in young psychophysiological insomniacs.

BACKGROUND: The presence of psychiatric disorders (according to DSM-III-R), the discriminating power of a psychiatric structured interview, and sleep monitoring were investigated in psychophysiological insomnia. METHOD: Forty young (20-40 years old) patients, selected for putative psychophysiological insomnia, underwent a psychiatric structured interview and home ambulatory sleep monitoring for 2 nights. The results were compared with those of a group of nine young normal sleepers. RESULTS: 48% of the insomniacs showed some psychiatric disorders, while 52% did not meet DSM-III-R criteria for a psychiatric diagnosis. Both groups, but not the controls, showed a slight first-night effect in the sleep analysis. The sleep structure of all insomniacs was found to be disturbed, mainly in sleep continuity, but essentially the two groups showed no significant differences. When we used a stepwise logistic regression analysis, the number of sleep stage shifts (indicating sleep instability) was the best variable in discriminating the insomniacs from controls, but not the patients with psychiatric disturbances from those without psychopathologies. CONCLUSION: The evaluation of young insomniacs with a structured psychiatric interview rather than with ambulatory sleep monitoring seems to be most useful in discriminating between patients with only psychophysiological insomnia and patients with both insomnia and an associated diagnosis of another mental disorder.

Adult↗