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1.
Arq. neuropsiquiatr ; 69(2b): 304-309, 2011. ilus
Article in English | LILACS | ID: lil-588088

ABSTRACT

This study aimed to elucidate cortical mechanisms involved in anticipatory actions when 23 healthy right-handed subjects had to catch a free falling object through quantitative electroencephalogram (qEEG). For this reason, we used coherence that represents a measurement of linear covariation between two signals in the frequency domain. In addition, we investigated gamma-band (30-100 Hz) activity that is related to cognitive and somatosensory processes. We hypothesized that gamma coherence will be increase in both parietal and occipital areas during moment after ball drop, due to their involvement in manipulation of objects, visuospatial processing, visual perception, stimuli identification and attention processes. We confirmed our hypothesis, an increase in gamma coherence on P3-P4 (t= -2.15; p=0.033) and PZ-OZ (t= -2.16; p=0.034) electrode pairs was verified for a paired t-test. We conclude that to execute tasks involving anticipatory movements (feedforward mechanisms), like our own task, probably, there is no need of a strong participation of visual areas in the process of information organization to manipulate objects and to process visuospatial information regarding the contact hand-object.


Este estudo teve como objetivo elucidar os mecanismos corticais envolvidos em ações antecipatórias quando 23 indivíduos saudáveis destros tinham que apreender um objeto em queda livre, através da eletroencefalografia quantitativa (EEGq). Por esta razão, usamos a coerência que representa a covariação linear entre dois sinais no domínio da frequência. Além disso, investigamos a atividade da banda gama (30-100 Hz), que está relacionada à processos cognitivos e somato-sensoriais. Nossa hipótese é que a coerência de gama estará aumentada em ambas as áreas parietais e occipitais durante o momento pós-queda da bola, devido ao seu envolvimento na manipulação de objetos, processamento visuo-espacial, percepção visual, identificação de estímulos e processos de atenção. Confirmamos nossa hipótese. Um aumento de coerência em gama nos pares de eletrodos P3-P4 (t= -2,15; p=0,033) e PZ-OZ (t= -2,16; p=0,034) foi verificado por teste-t pareado. Conclui-se que, para executar tarefas que envolvem movimentos de antecipação (mecanismos de retro-alimentação) como a nossa própria tarefa, provavelmente, não há necessidade de forte participação de áreas visuais no processo de organização da informação como para manipular objetos e processar a informação visuo-espacial no contato mão-objeto.


Subject(s)
Adult , Female , Humans , Male , Electroencephalography/methods , Functional Laterality/physiology , Psychomotor Performance/physiology , Visual Perception/physiology , Brain Mapping , Occipital Lobe/physiology , Parietal Lobe/physiology
2.
Braz. j. med. biol. res ; 43(6): 585-592, June 2010. ilus, tab
Article in English | LILACS | ID: lil-548274

ABSTRACT

The effect of physical exercise on the treatment of depressive elderly adults has not been investigated thus far in terms of changes in cortical hemispheric activity. The objective of the present study was to identify changes in depressive symptoms, quality of life, and cortical asymmetry produced by aerobic activity. Elderly subjects with a diagnosis of major depressive disorder (DSM-IV) were included. Twenty patients (70 percent females, 71 ± 3 years) were divided into an exercise group (pharmacological treatment plus aerobic training) and a control group (undergoing pharmacological treatment) in a quasi-experimental design. Pharmacological treatment was maintained stable throughout the study (antidepressants and anxiolytics). Subjects were evaluated by depression scales (Beck Depression Inventory, Hamilton Depression Rating Scale, Montgomery-Asberg Depression Rating Scale) and the Short Form Health Survey-36, and electroencephalographic measurements (frontal and parietal alpha asymmetry) before and after 1 year of treatment. After 1 year, the control group showed a decrease in cortical activity on the right hemisphere (increase of alpha power), which was not observed in the exercise group. The exercise group showed a significant decrease of depressive symptoms, which was not observed in the control group. This result was also accompanied by improved treatment response and remission rate after 1 year of aerobic exercise associated with treatment. This study provides support for the effect of aerobic training on alpha activity and on depressive symptoms in elderly patients. Exercise facilitates the treatment of depressive elderly adults, leading to clinical and physical improvement and protecting against a decrease in cortical activity.


Subject(s)
Aged , Female , Humans , Male , Middle Aged , Alpha Rhythm , Depressive Disorder, Major/therapy , Exercise Therapy/methods , Quality of Life , Anti-Anxiety Agents/therapeutic use , Antidepressive Agents/therapeutic use , Combined Modality Therapy , Depressive Disorder, Major/psychology , Electroencephalography , Follow-Up Studies , Psychiatric Status Rating Scales
3.
Braz. j. med. biol. res ; 38(7)July 2005. ilus
Article in English | LILACS | ID: lil-403863

ABSTRACT

Caffeine is the most consumed psychoactive substance in the world. The effects of caffeine have been studied using cognitive and motor measures, quantitative electroencephalography (qEEG) and event-related potentials. However, these methods are not usually employed in combination, a fact that impairs the interpretation of the results. The objective of the present study was to analyze changes in electrophysiological, cognitive and motor variables with the ingestion of caffeine, and to relate central to peripheral responses. For this purpose we recorded event-related potentials and eyes-closed, resting EEG, applied the Stroop test, and measured reaction time. Fifteen volunteers took caffeine (400 mg) or placebo in a randomized, crossover, double-blind design. A significant reduction of alpha absolute power over the entire scalp and of P300 latency at the Fz electrode were observed after caffeine ingestion. These results are consistent with a stimulatory effect of caffeine, although there was no change in the attention (Stroop) test or in reaction time. The qEEG seems to be the most sensitive index of the changes produced by caffeine in the central nervous system since it proved to be capable of detecting changes that were not evident in the tests of cognitive or motor performance.


Subject(s)
Adult , Female , Humans , Male , Caffeine/pharmacology , Central Nervous System Stimulants/pharmacology , Central Nervous System/drug effects , Cognition/drug effects , Electroencephalography/drug effects , Psychomotor Performance/drug effects , Analysis of Variance , Cross-Over Studies , Double-Blind Method , Electrophysiology , /drug effects , Reaction Time
4.
Psiquiatr. biol ; 8(4): 109-117, dez. 2000. tab, graf
Article in Portuguese | LILACS | ID: lil-298988

ABSTRACT

A sensibilidade da eletroencefalografia em detectar correlatos de disturbios psiquiatricos aaumentou com o advento de metodos quantitativos de analise (EEGq). parametros quantitativos säo extraídos de, pelo menos, dois minutos de registro EEGrafico, livres de artefato, ao repouso vigil e com as palpebras cerradas, com transformaçäo logarítmica para a obtençäo da Gaussianidade, submetidos a regressäo relativa a idade e transformados em escores Z. Um pequeno subgrupo de parametros da EEGq foi utilizado na construçäo de funçoes classificatorias. O presente estudo, ao utilizar este metodo, demonstrou uma alta precisäo, numa replicaçäo independente, em separar esquizofrenia de depressäo maior


Subject(s)
Humans , Adolescent , Adult , Middle Aged , Depression/diagnosis , Electroencephalography , Schizophrenia
5.
Psiquiatr. biol ; 4(4): 213-7, dez. 1996. tab
Article in Portuguese | LILACS | ID: lil-187227

ABSTRACT

O autor faz uma breve revisao da açao dos novos antipsicóticos sobre o humor em pacientes esquizofrênicos, com base em seus mecanismos de açao ao nível sináptico. Aponta, também, para o diagnóstico diferencial entre depressao, de um lado, e sintomas negativos e distúrbios extrapiramidais, de outro.


Subject(s)
Humans , Antipsychotic Agents/pharmacology , Irritable Mood , Schizophrenia , Antipsychotic Agents/adverse effects , Depression/diagnosis , Diagnosis, Differential , Psychotic Disorders/diagnosis
6.
Psiquiatr. biol ; 3(2): 22-8, jul. 1995. ilus
Article in Portuguese | LILACS | ID: lil-193700

ABSTRACT

O autor descreve as vantagens do Mapeamento Cerebral, no Domínio do Tempo, das Epilepsias em comparaçäo com o Método da Eletroencefalografia Convencional.


Subject(s)
Humans , Brain Mapping , Epilepsy/diagnosis , Electroencephalography
7.
Psiquiatr. biol ; 2(3): 21-9, nov. 1994. ilus
Article in Portuguese | LILACS | ID: lil-194330

ABSTRACT

O autor revisa e exemplifica parâmetros da Eletroencefalografia Quatitativa (Mapeamento da Atividade Elétrica Cerebral) sugestivos para o diagnóstico de Epilepsia Rolândica Benigna (Epilepsia Focal Benigna da Infância com Pontas Centro-Temporal).


Subject(s)
Humans , Female , Child , Brain Mapping , Epilepsy, Rolandic/physiopathology
8.
J. bras. psiquiatr ; 33(5): 351-6, 1984.
Article in Portuguese | LILACS | ID: lil-23398

ABSTRACT

A discinesia tardia talves seja a complicacao mais importante associada ao uso cronico de medicacoes antipsicoticas. Se, por um lado, ha evidencia da participacao dos neurolepticos na discinesia tardia,por outro, isso nao implica a existencia de uma relacao causal entre ambos. Ate o presente momento estas evidencias sao apenas epidemiologicas. Pelo fato de que apenas parte da populacao submetida ao tratamento com neurolepticos apresenta o quadro clinico de discinesia tardia, e bem provavel que outros fatores (idade, sexo, doenca organico-cerebral, sindromes extra-piramidais pregressas, uso pregresso de medicacoes antiparkinsonianas anticolinergicas e entidade nosologica) possam contribuir para o desenvolvimento desse disturbio do movimento


Subject(s)
Humans , Male , Female , Antipsychotic Agents , Dyskinesia, Drug-Induced
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