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1.
Brain Topogr ; 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37402859

RESUMO

The current study aimed to investigate alterations of event-related potentials (ERPs) microstate during reward anticipation in subjects with schizophrenia (SCZ), and their association with hedonic experience and negative symptoms. EEG data were recorded in thirty SCZ and twenty-three healthy controls (HC) during the monetary incentive delay task in which reward, loss and neutral cues were presented. Microstate analysis and standardized low-resolution electromagnetic tomography (sLORETA) were applied to EEG data. Furthermore, analyses correlating a topographic index (the ERPs score), calculated to quantify brain activation in relationship to the microstate maps, and scales assessing hedonic experience and negative symptoms were performed. Alterations in the first (125.0-187.5 ms) and second (261.7-414.1 ms) anticipatory cue-related microstate classes were observed. In SCZ, reward cues were associated to shorter duration and earlier offset of the first microstate class as compared to the neutral condition. In the second microstate class, the area under the curve was smaller for both reward and loss anticipation cues in SCZ as compared to HC. Furthermore, significant correlations between ERPs scores and the anticipation of pleasure scores were detected, while no significant association was found with negative symptoms. sLORETA analysis showed that hypo-activation of the cingulate cortex, insula, orbitofrontal and parietal cortex was detected in SCZ as compared to HC. Abnormalities in ERPs could be traced already during the early stages of reward processing and were associated with the anticipation of pleasure, suggesting that these dysfunctions might impair effective evaluation of incoming pleasant experiences. Negative symptoms and anhedonia are partially independent results.

2.
Psychol Med ; 48(8): 1359-1366, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29017620

RESUMO

BACKGROUND: The increased use of the MATRICS Consensus Cognitive Battery (MCCB) to investigate cognitive dysfunctions in schizophrenia fostered interest in its sensitivity in the context of family studies. As various measures of the same cognitive domains may have different power to distinguish between unaffected relatives of patients and controls, the relative sensitivity of MCCB tests for relative-control differences has to be established. We compared MCCB scores of 852 outpatients with schizophrenia (SCZ) with those of 342 unaffected relatives (REL) and a normative Italian sample of 774 healthy subjects (HCS). We examined familial aggregation of cognitive impairment by investigating within-family prediction of MCCB scores based on probands' scores. METHODS: Multivariate analysis of variance was used to analyze group differences in adjusted MCCB scores. Weighted least-squares analysis was used to investigate whether probands' MCCB scores predicted REL neurocognitive performance. RESULTS: SCZ were significantly impaired on all MCCB domains. REL had intermediate scores between SCZ and HCS, showing a similar pattern of impairment, except for social cognition. Proband's scores significantly predicted REL MCCB scores on all domains except for visual learning. CONCLUSIONS: In a large sample of stable patients with schizophrenia, living in the community, and in their unaffected relatives, MCCB demonstrated sensitivity to cognitive deficits in both groups. Our findings of significant within-family prediction of MCCB scores might reflect disease-related genetic or environmental factors.


Assuntos
Disfunção Cognitiva/diagnóstico , Família/psicologia , Esquizofrenia/complicações , Psicologia do Esquizofrênico , Adulto , Idoso , Cognição , Consenso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais/psicologia , Escalas de Graduação Psiquiátrica , Psicometria
3.
Acta Psychiatr Scand ; 138(3): 253-266, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29984409

RESUMO

OBJECTIVE: The study aimed to explore premorbid academic and social functioning in patients with schizophrenia, and its associations with the severity of negative symptoms and neurocognitive impairment. METHOD: Premorbid adjustment (PA) in patients with schizophrenia was compared to early adjustment in unaffected first-degree relatives and healthy controls. Its associations with psychopathology, cognition, and real-life functioning were investigated. The associations of PA with primary negative symptoms and their two factors were explored. RESULTS: We found an impairment of academic and social PA in patients (P ≤ 0.000001) and an impairment of academic aspects of early adjustment in relatives (P ≤ 0.01). Patients with poor PA showed greater severity of negative symptoms (limited to avolition after excluding the effect of depression/parkinsonism), working memory, social cognition, and real-life functioning (P ≤ 0.01 to ≤0.000001). Worse academic and social PA were associated with greater severity of psychopathology, cognitive impairment, and real-life functioning impairment (P ≤ 0.000001). Regression analyses showed that worse PA in the academic domain was mainly associated to the impairment of working memory, whereas worse PA in the social domain to avolition (P ≤ 0.000001). CONCLUSION: Our findings suggest that poor early adjustment may represent a marker of vulnerability to schizophrenia and highlight the need for preventive/early interventions based on psychosocial and/or cognitive programs.


Assuntos
Desempenho Acadêmico/psicologia , Transtornos Cognitivos/psicologia , Disfunção Cognitiva/psicologia , Esquizofrenia/diagnóstico , Desempenho Acadêmico/tendências , Adulto , Idoso , Cognição/fisiologia , Transtornos Cognitivos/diagnóstico , Disfunção Cognitiva/diagnóstico , Depressão/epidemiologia , Depressão/psicologia , Feminino , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Pessoa de Meia-Idade , Motivação , Escalas de Graduação Psiquiátrica/normas , Psicopatologia , Esquizofrenia/epidemiologia , Esquizofrenia/terapia , Psicologia do Esquizofrênico , Índice de Gravidade de Doença , Ajustamento Social , Comportamento Social
4.
Psychol Med ; 46(13): 2717-29, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27649341

RESUMO

BACKGROUND: The study aimed to subtype patients with schizophrenia on the basis of social cognition (SC), and to identify cut-offs that best discriminate among subtypes in 809 out-patients recruited in the context of the Italian Network for Research on Psychoses. METHOD: A two-step cluster analysis of The Awareness of Social Inference Test (TASIT), the Facial Emotion Identification Test and Mayer-Salovey-Caruso Emotional Intelligence Test scores was performed. Classification and regression tree analysis was used to identify the cut-offs of variables that best discriminated among clusters. RESULTS: We identified three clusters, characterized by unimpaired (42%), impaired (50.4%) and very impaired (7.5%) SC. Three theory-of-mind domains were more important for the cluster definition as compared with emotion perception and emotional intelligence. Patients more able to understand simple sarcasm (⩾14 for TASIT-SS) were very likely to belong to the unimpaired SC cluster. Compared with patients in the impaired SC cluster, those in the very impaired SC cluster performed significantly worse in lie scenes (TASIT-LI <10), but not in simple sarcasm. Moreover, functioning, neurocognition, disorganization and SC had a linear relationship across the three clusters, while positive symptoms were significantly lower in patients with unimpaired SC as compared with patients with impaired and very impaired SC. On the other hand, negative symptoms were highest in patients with impaired levels of SC. CONCLUSIONS: If replicated, the identification of such subtypes in clinical practice may help in tailoring rehabilitation efforts to the person's strengths to gain more benefit to the person.


Assuntos
Inteligência Emocional/fisiologia , Expressão Facial , Reconhecimento Facial/fisiologia , Esquizofrenia/fisiopatologia , Percepção Social , Senso de Humor e Humor como Assunto , Adulto , Análise por Conglomerados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Psychol Med ; 45(8): 1765-78, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25577954

RESUMO

BACKGROUND: The neurobiological underpinnings of avolition in schizophrenia remain unclear. Most brain imaging research has focused on reward prediction deficit and on ventral striatum dysfunction, but findings are not consistent. In the light of accumulating evidence that both ventral striatum and dorsal caudate play a key role in motivation, we investigated ventral striatum and dorsal caudate activation during processing of reward or loss in patients with schizophrenia. METHOD: We used functional magnetic resonance imaging to study brain activation during a Monetary Incentive Delay task in patients with schizophrenia, treated with second-generation antipsychotics only, and in healthy controls (HC). We also assessed the relationships of ventral striatum and dorsal caudate activation with measures of hedonic experience and motivation. RESULTS: The whole patient group had lower motivation but comparable hedonic experience and striatal activation than HC. Patients with high avolition scores showed lower dorsal caudate activation than both HC and patients with low avolition scores. A lower dorsal caudate activation was also observed in patients with deficit schizophrenia compared to HC and patients with non-deficit schizophrenia. Dorsal caudate activity during reward anticipation was significantly associated with avolition, but not with anhedonia in the patient group. CONCLUSIONS: These findings suggest that avolition in schizophrenia is linked to dorsal caudate hypoactivation.


Assuntos
Antecipação Psicológica/fisiologia , Encéfalo/fisiopatologia , Imageamento por Ressonância Magnética , Motivação/fisiologia , Recompensa , Esquizofrenia/fisiopatologia , Adulto , Mapeamento Encefálico , Retroalimentação Psicológica/fisiologia , Feminino , Humanos , Masculino
6.
Reprod Fertil Dev ; 2015 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-26020798

RESUMO

Plasma prolactin (PRL) concentrations in captive koalas during lactation were determined by serial blood sampling. PRL concentrations were low (1.3 ± 0.1 ng mL-1; n = 5) during early lactation until pouch young (PY) began to emerge from the pouch (around Day 130) before significantly (P < 0.05) increasing between Day 161 and Day 175 (5.3 ± 1.0 ng mL-1). A significant (P < 0.001) peak in PRL (7.7 ± 0.6 ng mL-1) coincided with maturing young between Day 189 and Day 231. All females failed to exhibit any signs of oestrous behaviour until Day 268.8 ± 8.5 (n = 4), some 102 ± 19 days before PY were weaned following achieving target weights of 2.5-2.7 kg. Throughout lactation, plasma LH concentrations were relatively high (range 4.9-8.7 ng mL-1) and LH responses to exogenous gonadotrophin-releasing hormone were observed in all koalas at all times during lactation.

7.
Reprod Fertil Dev ; 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25929179

RESUMO

The present study examined the effectiveness of the gonadotrophin-releasing hormone (GnRH) antagonist azaline B to suppress plasma LH and 17ß-oestradiol concentrations in koalas and its potential application for oestrous synchronisation. In Experiment 1, single subcutaneous injections of azaline B successfully blocked the LH response to exogenous mammalian (m) GnRH in a dose-dependent manner; specifically, 0 mg (n = 4) did not suppress the LH response, 1 mg azaline B (n = 6) suppressed the LH response for 24 h (P < 0.05), 3.3 mg azaline B (n = 8) suppressed the LH response significantly in all animals only for 3 h (P < 0.05), although in half the animals LH remained suppressed for up to 3 days, and 10 mg azaline B (n = 4) suppressed the LH response for 7 days (P < 0.05). In Experiment 2, daily 1 mg, s.c., injections of azaline B over a 10-day period during seasonal anoestrus (June-July; n = 6) suppressed (P < 0.01) the LH response to mGnRH consecutively over the 10-day treatment period and, 4 days after cessation of treatment, the LH response had not recovered. Experiment 3 was designed to test the efficacy of daily 1 mg, s.c., azaline B over 10 days to suppress plasma LH and 17ß-oestradiol concentrations and ultimately synchronise timed return to oestrus during the breeding season. Although azaline B treatment did not suppress basal LH or 17ß-oestradiol, oestrus was delayed in all treated females by 24.2 days, but with high variability (range 9-39 days). Overall, the present study demonstrates that the GnRH antagonist azaline B is able to inhibit the LH response in koalas to exogenous mGnRH and successfully delay the return to oestrus. However, although azaline B clearly disrupts folliculogenesis, it has not been able to effectively synchronise return to oestrus in the koala.

8.
Reprod Fertil Dev ; 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25929260

RESUMO

This study investigated the efficacy of a synthetic progestogen, levonorgestrel (LNG), to control koala ovarian activity for the purposes of oestrous synchronisation. Captive koalas were administered either saline control or a 70-mg LNG implant on Day 2 of oestrus. Urogenital cytology, oestrous behaviour and plasma oestradiol-17ß and LH concentrations were monitored over a 6-week period. After LNG implant removal females were monitored to determine if the return to oestrus was synchronised. LNG-treated koalas immediately ceased displaying oestrous behaviour, showed no evidence of cornified epithelial cells in smears of urogenital cytology and exhibited low plasma oestradiol-17ß concentrations throughout the implantation period. In contrast, oestradiol-17ß levels in control koalas showed evidence of continued cyclic activity associated with behavioural oestrus and increased cornified epithelial cells in urogenital smears on Days 33 to 35 after saline injection. After implant removal, LNG-treated koalas exhibited oestrus at 13, 14, 17 and 30 days after implant removal. Plasma LH concentrations varied throughout the study period with no significant time (P = 0.49) or treatment (P = 0.13) effect. Overall results from this study suggest that LNG implants in koalas can inhibit oestrous behaviour and reduce circulating oestradiol-17ß levels before oestrus, most likely by preventing development of the pre-ovulatory follicle. However, there was no evidence of LH suppression by the LNG implants. Removal of LNG implants resulted in the synchronous return to oestrus in three of the four treated koalas. Further studies on a larger population are required to validate these findings.

9.
Psychol Med ; 41(4): 839-48, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20594380

RESUMO

BACKGROUND: Studies investigating neurocognitive impairment in subjects with eating disorders (EDs) have reported heterogeneous patterns of impairment and, in some instances, no dysfunction. The present study aimed to define the pattern of neurocognitive impairment in a large sample of bulimia nervosa (BN) patients and to demonstrate that neuroendocrine, personality and clinical characteristics influence neurocognitive performance in BN. METHOD: Attention/immediate memory, set shifting, perseveration, conditional and implicit learning were evaluated in 83 untreated female patients with BN and 77 healthy controls (HC). Cortisol and 17ß-estradiol plasma levels were assessed. Cloninger's Temperament and Character Inventory - Revised (TCI-R), the Bulimic Investigation Test Edinburgh (BITE) and the Montgomery-Asberg Depression Rating Scale (MADRS) were administered. RESULTS: No impairment of cognitive performance was found in subjects with BN compared with HC. Cortisol and 'Self-directedness' were associated with better performance on conditional learning whereas 17ß-estradiol had a negative influence on this domain; 'Reward dependence' was associated with worse performance on implicit learning; and depressive symptomatology influenced performance on the Wisconsin Card Sorting Test (WCST) negatively. CONCLUSIONS: No cognitive impairment was found in untreated patients with BN. Neuroendocrine, personality and clinical variables do influence neurocognitive functioning and might explain discrepancies in literature findings.


Assuntos
Bulimia Nervosa/diagnóstico , Bulimia Nervosa/psicologia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/psicologia , Testes Neuropsicológicos/estatística & dados numéricos , Adolescente , Adulto , Aprendizagem por Associação , Atenção , Função Executiva , Feminino , Humanos , Memória de Curto Prazo , Reversão de Aprendizagem , Aprendizagem Seriada , Adulto Jovem
10.
Eur Psychiatry ; 64(1): e21, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33726883

RESUMO

Negative symptoms of schizophrenia remain a major therapeutic challenge. The progress in the conceptualization and assessment is not yet fully reflected by treatment research. Nevertheless, there is a growing evidence base regarding the effects of biological and psychosocial interventions on negative symptoms. The importance of the distinction between primary and secondary negative symptoms for treatment selection might seem evident, but the currently available evidence remains limited. Good clinical practice is recommended for the treatment of secondary negative symptoms. Antipsychotic treatment should be optimized to avoid secondary negative symptoms due to side effects and due to positive symptoms. For most available interventions, further evidence is needed to formulate sound recommendations for primary, persistent, or predominant negative symptoms.However, based on currently available evidence recommendations for the treatment of undifferentiated negative symptoms (including both primary and secondary negative symptoms) are provided. Although it has proven difficult to formulate an evidence-based recommendation for the choice of an antipsychotic, a switch to a second-generation antipsychotic should be considered for patients who are treated with a first-generation antipsychotic. Antidepressant add-on to antipsychotic treatment is an option. Social skills training is recommended as well as cognitive remediation for patients who also show cognitive impairment. Exercise interventions also have shown promise. Finally, access to treatment and to psychosocial rehabilitation should be ensured for patients with negative symptoms. Overall, there is definitive progress in the field, but further research is clearly needed to develop specific treatments for negative symptoms.


Assuntos
Guias de Prática Clínica como Assunto , Esquizofrenia , Antidepressivos/uso terapêutico , Antipsicóticos/uso terapêutico , Humanos , Esquizofrenia/tratamento farmacológico
11.
Eur Psychiatry ; 64(1): e23, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33597064

RESUMO

BACKGROUND: During the last decades, a renewed interest for negative symptoms (NS) was brought about by the increased awareness that they interfere severely with real-life functioning, particularly when they are primary and persistent. METHODS: In this guidance paper, we provide a systematic review of the evidence and elaborate several recommendations for the conceptualization and assessment of NS in clinical trials and practice. RESULTS: Expert consensus and systematic reviews have provided guidance for the optimal assessment of primary and persistent negative symptoms; second-generation rating scales, which provide a better assessment of the experiential domains, are available; however, NS are still poorly assessed both in research and clinical settings.This European Psychiatric Association (EPA) guidance recommends the use of persistent negative symptoms (PNS) construct in the context of clinical trials and highlights the need for further efforts to make the definition of PNS consistent across studies in order to exclude as much as possible secondary negative symptoms. We also encourage clinicians to use second-generation scales, at least to complement first-generation ones.The EPA guidance further recommends the evidence-based exclusion of several items included in first-generation scales from any NS summary or factor score to improve NS measurement in research and clinical settings. Self-rated instruments are suggested to further complement observer-rated scales in NS assessment.Several recommendations are provided for the identification of secondary negative symptoms in clinical settings. CONCLUSIONS: The dissemination of this guidance paper may promote the development of national guidelines on negative symptom assessment and ultimately improve the care of people with schizophrenia.


Assuntos
Esquizofrenia , Humanos , Escalas de Graduação Psiquiátrica , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Avaliação de Sintomas
12.
Science ; 205(4409): 904-5, 1979 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-17813084

RESUMO

Magnesian calcite overgrowth containing 4 (+/- 2) mole percent magnesium carbonate forms on calcite exposed to natural seawater near the ocean surface. This magnesian calcite is approximately 30 percent less soluble in seawater than pure calcite. The formation of the magnesian calcite of reduced solubility may have a major influence on calcite accumulation in deep sea sediments.

13.
Brain Res Bull ; 73(4-6): 220-30, 2007 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-17562387

RESUMO

The P3 is probably the most well known component of the brain event-related potentials (ERPs). Using a three-tone oddball paradigm two different components can be identified: the P3b elicited by rare target stimuli and the P3a elicited by the presentation of rare non-target stimuli. Although the two components may partially overlap in time and space, they have a different scalp topography suggesting different neural generators. The present study is aimed at defining the scalp topography of the two P3 components by means of reference-independent methods and identifying their electrical cortical generators by using the low-resolution electromagnetic tomography (LORETA). ERPs were recorded during a three-tone oddball task in 32 healthy, right-handed university students. The scalp topography of the P3 components was assessed by means of the brain electrical microstates technique and their cortical sources were evaluated by LORETA. P3a and P3b showed different scalp topography and cortical sources. The P3a electrical field had a more anterior distribution as compared to the P3b and its generators were localized in cingulate, frontal and right parietal areas. P3b sources included bilateral frontal, parietal, limbic, cingulate and temporo-occipital regions. Differences in scalp topography and cortical sources suggest that the two components reflect different neural processes. Our findings on cortical generators are in line with the hypothesis that P3a reflects the automatic allocation of attention, while P3b is related to the effortful processing of task-relevant events.


Assuntos
Córtex Cerebral , Fenômenos Eletromagnéticos/métodos , Potenciais Evocados P300/fisiologia , Potenciais Evocados Auditivos/fisiologia , Tomografia/métodos , Estimulação Acústica , Adolescente , Adulto , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/fisiologia , Feminino , Humanos , Masculino
14.
Oncol Rep ; 16(3): 543-53, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16865254

RESUMO

The present study reports the characteristics of the biochemical profile of human gastric adenocarcinoma in comparison with that of healthy gastric mucosa, using ex vivo HR-MAS Magnetic Resonance Spectroscopy. Healthy human mucosa is mainly characterized by the presence of small metabolites (more than 50 identified) and macromolecules, whereas the adenocarcinoma spectra are dominated by the presence of signals due to triglycerides, whose content on the contrary is very low in healthy gastric mucosa. The use of spin-echo experiments enable us to detect some metabolites in the unhealthy tissues and to determine their variation with respect to the healthy ones. We have observed that the Cho:ChoCC ratio changes from 20:80 in the healthy tissues to 80:20 in the neoplastic gastric mucosa.


Assuntos
Adenocarcinoma/metabolismo , Biomarcadores Tumorais/metabolismo , Mucosa Gástrica/metabolismo , Espectroscopia de Ressonância Magnética , Neoplasias Gástricas/metabolismo , Adenocarcinoma/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Ácidos Graxos/metabolismo , Feminino , Mucosa Gástrica/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias Gástricas/diagnóstico
15.
Clin Neurophysiol ; 127(4): 2149-60, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26853737

RESUMO

OBJECTIVE: Investigate impairment of reward anticipation in subjects with schizophrenia (SCZ) and its association with negative symptom dimensions and hedonic experience. METHODS: Event-related potentials (ERPs) were recorded, in thirty SCZ and twenty-three matched healthy controls (HC), during a "Monetary Incentive Delay" task in which reward and loss cues (incentive cues of positive and negative value) of different magnitude, as well as neutral cues were presented. ASSESSMENTS: anticipatory and consummatory pleasure, trait anhedonia and motivation in all subjects; avolition and expressive deficit in SCZ. RESULTS: SCZ had lower motivation but comparable hedonic experience with respect to HC. In HC, during reward anticipation, the early P3 was larger for large magnitude incentives, irrespective of their valence, while the late P3 was larger for large reward. In SCZ, early P3 did not discriminate the incentive magnitude and the late P3 was larger for large loss. Early P3 amplitude for large magnitude incentives was inversely related to trait social anhedonia but not to negative symptoms dimensions. CONCLUSIONS: SCZ are unable to integrate the incentive magnitude and reward value of future events in the context of their ongoing task. P3 abnormalities are associated with trait anhedonia, but not with negative symptoms dimensions. SIGNIFICANCE: In line with recent studies, our findings indicate that anhedonia and avolition are partially independent constructs.


Assuntos
Anedonia/fisiologia , Antecipação Psicológica/fisiologia , Recompensa , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Esquizofrenia/fisiopatologia , Adulto Jovem
16.
Neuroscience ; 136(1): 323-32, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16203106

RESUMO

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.


Assuntos
Córtex Auditivo/fisiologia , Testes com Listas de Dissílabos , Dominância Cerebral , Eletroencefalografia , Estimulação Acústica/métodos , Adulto , Feminino , Humanos , Masculino
17.
Int J Mol Med ; 16(2): 301-7, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16012766

RESUMO

The present case report was aimed at identifying the molecular profile characteristic of a primitive neuro-ectodermal tumor (PNET) in a 3-year-old child affected by a lesion localized in the cerebellar region. The histological diagnosis was medulloblastoma. In vivo single voxel 1H magnetic resonance spectroscopy (MRS) shows high specificity in detecting the main metabolic alterations in the primitive cerebellar lesion; a very high amount of the choline-containing compounds and very low level of creatine derivatives and N-acetylaspartate. Ex vivo high resolution magic angle spinning (HR-MAS) 1H magnetic resonance spectroscopy, performed at 9.4 Tesla on the neoplastic specimen collected during surgery, allows for the unambiguous identification of several metabolites giving a more in-depth evaluation of the metabolic pattern of the lesion. The ex vivo HR-MAS MR spectra show that the spectral detail is much higher than that obtained in vivo and that, for example, myo-inositol, taurine and phosphorylethanolamine contribute to the in vivo signal at 3.2 ppm, usually attributed to choline-containing compounds. In addition, the spectroscopic data appear to correlate with some morphological features of the medulloblastoma. Consequently, the present study shows that ex vivo HR-MAS 1H MRS is able to strongly improve the clinical possibility of in vivo MRS and can be used in conjunction with in vivo spectroscopy for clinical purposes.


Assuntos
Neoplasias Cerebelares/diagnóstico , Espectroscopia de Ressonância Magnética/métodos , Meduloblastoma/diagnóstico , Tumores Neuroectodérmicos Primitivos/diagnóstico , Antígeno CD56/análise , Neoplasias Cerebelares/metabolismo , Pré-Escolar , Diagnóstico Diferencial , Humanos , Imuno-Histoquímica , Masculino , Meduloblastoma/metabolismo , Tumores Neuroectodérmicos Primitivos/metabolismo
18.
Eur Psychiatry ; 30(5): 641-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25758156

RESUMO

BACKGROUND: The Brief Negative Symptom Scale (BNSS) was developed to address the main limitations of the existing scales for the assessment of negative symptoms of schizophrenia. The initial validation of the scale by the group involved in its development demonstrated good convergent and discriminant validity, and a factor structure confirming the two domains of negative symptoms (reduced emotional/verbal expression and anhedonia/asociality/avolition). However, only relatively small samples of patients with schizophrenia were investigated. Further independent validation in large clinical samples might be instrumental to the broad diffusion of the scale in clinical research. METHODS: The present study aimed to examine the BNSS inter-rater reliability, convergent/discriminant validity and factor structure in a large Italian sample of outpatients with schizophrenia. RESULTS: Our results confirmed the excellent inter-rater reliability of the BNSS (the intraclass correlation coefficient ranged from 0.81 to 0.98 for individual items and was 0.98 for the total score). The convergent validity measures had r values from 0.62 to 0.77, while the divergent validity measures had r values from 0.20 to 0.28 in the main sample (n=912) and in a subsample without clinically significant levels of depression and extrapyramidal symptoms (n=496). The BNSS factor structure was supported in both groups. CONCLUSIONS: The study confirms that the BNSS is a promising measure for quantifying negative symptoms of schizophrenia in large multicenter clinical studies.


Assuntos
Sintomas Afetivos/diagnóstico , Escalas de Graduação Psiquiátrica Breve/normas , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Adulto , Sintomas Afetivos/psicologia , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Psicometria , Reprodutibilidade dos Testes
19.
Biol Psychiatry ; 35(6): 367-74, 1994 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8018782

RESUMO

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.


Assuntos
Clopentixol/uso terapêutico , Relação Dose-Resposta a Droga , Eletroencefalografia , Haloperidol/uso terapêutico , Esquizofrenia/tratamento farmacológico , Resultado do Tratamento , Adolescente , Adulto , Encéfalo/efeitos dos fármacos , Clopentixol/administração & dosagem , Clopentixol/farmacologia , Feminino , Haloperidol/administração & dosagem , Haloperidol/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Esquizofrenia/diagnóstico
20.
Schizophr Res ; 6(1): 15-23, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1786232

RESUMO

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.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/fisiopatologia , Eletroencefalografia/efeitos dos fármacos , Haloperidol/uso terapêutico , Esquizofrenia/tratamento farmacológico , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Adulto , Mapeamento Encefálico/instrumentação , Doença Crônica , Relação Dose-Resposta a Droga , Eletroencefalografia/instrumentação , Potenciais Evocados/efeitos dos fármacos , Feminino , Humanos , Masculino , Processamento de Sinais Assistido por Computador/instrumentação
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