RESUMO
The electronic structure and magnetic properties of the graphene/Fe/Ni(111) system were investigated via combination of the density functional theory calculations and electron-spectroscopy methods. This system was prepared via intercalation of thin Fe layers (1 ML) underneath graphene on Ni(111) and its inert properties were verified by means of photoelectron spectroscopy. Intercalation of iron in the space between graphene and Ni(111) changes drastically the magnetic response from the graphene layer that is explained by the formation of the highly spin-polarized 3d(z(2)) quantum-well state in the thin iron layer.
RESUMO
To investigate whether surgical treatment of refractory epilepsy is associated with increased risk for serious psychopathology, 25 treated patients were compared with 25 current candidates for surgery matched on demographic and neuroepileptic characteristics. Diagnoses were made by the National Institute of Mental Health Diagnostic Interview Schedule. No differences between groups in lifetime or point prevalence rates were significant. The rate of psychosis in the postoperative group (8%) approximated the lower estimates in previous studies. Thus, surgical treatment of seizures did not increase the risk for psychopathology. However, patients with temporal lobe electroencephalogram foci or tumor as the epileptogenic lesion were more likely to have serious disorders than other patients. Also, anxiety disorders were more prevalent in our patient groups than in the general population.
Assuntos
Transtornos Mentais/epidemiologia , Neurocirurgia/efeitos adversos , Convulsões/cirurgia , Adolescente , Adulto , Feminino , Humanos , Masculino , Transtornos Mentais/etiologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Convulsões/psicologiaRESUMO
Face-recognition ability has been claimed to be qualitatively different from other pattern-recognition abilities. One argument for this claim is the finding of a significant right hemisphere advantage for the recognition of upright but not inverted faces. However, this argument is justified only if this orientation-sensitive pattern is unique to faces. In the present study, comparable patterns of orientation-sensitive involvement of the right hemisphere are found for the recognition of faces and houses. This finding is interpreted as evidence for a right hemisphere schema formation capacity that is applied not only to upright faces but also to other familiar classes of stimuli in their canonical upright orientation. It is suggested that any greater right hemisphere involvement in the recognition of upright faces is due to our greater expertise at recognizing faces than other stimulus types. We also find evidence that only a subset of right-handed adults show orientation-sensitive right hemisphere involvement in the recognition of faces and houses: in particular, those dextrals with a characteristic hemispheric arousal asymmetry in favor of the right hemisphere. In contrast, dextrals with a characteristic arousal asymmetry in favor of the left hemisphere do not show significant visual field asymmetries for faces or houses in either upright or inverted orientations.
Assuntos
Dominância Cerebral , Percepção de Forma , Orientação , Reconhecimento Visual de Modelos , Adolescente , Adulto , Nível de Alerta , Atenção , Aprendizagem por Discriminação , Face , Feminino , Humanos , MasculinoRESUMO
Stories were elicited from 29 epileptic patients with generalized, simple partial, and complex partial seizures with bilateral, right, or left foci, and from 32 persons in two control groups. Four older epileptic patients with long histories of left complex partial seizures were verbose. Their stories involved trivial and subjective details, consistent with circumstantiality and suggesting the substrate for a hallucinatory syndrome.
Assuntos
Epilepsia/psicologia , Fala , Adolescente , Adulto , Afeto , Fatores Etários , Idoso , Epilepsias Parciais/psicologia , Epilepsia do Lobo Temporal/psicologia , Feminino , Lateralidade Funcional , Alucinações/psicologia , Humanos , Masculino , Memória , Pessoa de Meia-Idade , Testes Neuropsicológicos , Percepção , Comportamento Verbal , Escalas de WechslerRESUMO
Evidence supporting individual variations in patterns of hemispheric involvement in the recognition of visuo-spatial and verbal stimuli among dextrals is reported. In Experiment 1, subjects' asymmetry scores on a task that was nonlateralized for the group as a whole were significantly correlated with their asymmetry scores on right-hemisphere-specialized tasks, including face recognition. In Experiment 2, subjects' asymmetry scores on a task that was nonlateralized for the group as a whole were significantly correlated with their asymmetry scores on a left-hemisphere-specialized word recognition task. These results suggest that individual dextrals' asymmetry scores on lateralized tasks are a joint function of a subject's underlying hemispheric specialization for that task and stable individual variations in asymmetric hemispheric reliance.
Assuntos
Dominância Cerebral , Lateralidade Funcional , Nível de Alerta , Face , Feminino , Percepção de Forma , Humanos , Masculino , Rememoração MentalRESUMO
Words and famous faces were tachistoscopically presented in bilateral view to normal right-handed subjects. A left visual field advantage was obtained for famous faces whether naming or recognition from an array was required and a right visual field advantage was obtained for words. While the finding of a left visual field advantage for the recognition of famous faces is consistent with studies of face recognition deficits in brain-damaged patients, a right visual field advantage for the recognition of famous faces has recently been reported in normal subjects. Possible explanations for this discrepancy are discussed.