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T Aström

Publications and source records attributed to T Aström.

6 recordsLinked to original sources

Relative electroencephalographic desynchronization and synchronization in humans to emotional film content: an analysis of the 4-6, 6-8, 8-10 and 10-12 Hz frequency bands.

The reactivity of different narrow electroencephalographic (EEG) frequencies (4-6, 6-8, 8-10 and 10-12 Hz) to three types of emotionally laden film clips (aggressive, sad, neutral) were examined. We observed that different EEG frequency bands responded differently to the three types of film content. In the 4-6 Hz frequency band, the viewing of aggressive film content elicited greater relative synchronization as compared the responses elicited by the viewing of sad and neutral film content. The 6-8 Hz and 8-10 Hz frequency bands exhibited reactivity to the chronological succession of film viewing whereas the responses of the 10-12 Hz frequency band evolved within minutes during film viewing. Our results propose dissociations between the responses of different frequencies within the EEG to different emotion-related stimuli. Narrow frequency band EEG analysis offers an adequate tool for studying cortical activation patterns during emotion-related information processing.

Adult↗

Cortical activation related to auditory semantic matching of concrete versus abstract words.

OBJECTIVE: The aim of this study was to examine cortical correlates of semantic memory processes in the auditory stimulus modality. METHODS: Event-related desynchronization (ERD) and synchronization (ERS) of the lower (8-10 Hz) and upper (10-12 Hz) alpha frequency bands of background EEG were studied in 10 subjects performing an auditory semantic matching task. The stimuli were abstract and concrete nouns which were presented sequentially in pairs. The task was to decide whether the two nouns belonged to the same semantic category or not. RESULTS: The presentation of the first stimulus (encoding) elicited ERS whereas the presentation of the second stimulus (semantic matching) elicited ERD. Abstract nouns presented as the second stimulus elicited ERD which was most prominent in the lower alpha frequency band, whereas the presentation of a concrete noun as the first stimulus elicited ERS, most prominently in the upper alpha frequency band. CONCLUSIONS: The auditorily elicited ERD/ERS reflects cortical activity associated with cognitive functions. The present findings demonstrate that the auditorily elicited ERD/ERS can reveal subtle differences in auditory information processing. Semantic memory processes (encoding and comparison) are reflected as varying responses in the two alpha frequency bands.

Acoustic Stimulation↗

Psychosocial function and life satisfaction after stroke.

BACKGROUND AND PURPOSE: This prospective study was designed to describe different aspects of psychosocial function after stroke and the development of changes over time. A major aim has been to identify mental, functional, and social factors associated with low life satisfaction late after stroke. METHODS: Social network, functional ability, leisure-time activities, experience of ill health, major depression, and life satisfaction were assessed repeatedly over 3 years in a population-based sample of 50 long-term survivors of stroke (mean age 71.4 years). RESULTS: Compared with a general elderly population, patients 3 years poststroke had more psychiatric symptoms, lower functional ability, and reduced life satisfaction. Contacts with children were maintained over the 3-year follow-up period, whereas contacts with friends and neighbors declined early after stroke and remained lower than in the general elderly population (p less than 0.05). When time dependency was analyzed, activities of daily living and somatic/neurological symptoms were found to change little after 3 months, while psychiatric symptoms showed changes later. Between 3 and 12 months poststroke, the prevalence of major depression decreased, leisure-time activities and social contacts were partly resumed, and life satisfaction improved (p less than 0.01). Once good life satisfaction was restored it was maintained, and poor life satisfaction at 1 year remained poor for the entire 3 years. CONCLUSIONS: It is concluded that major depression early after stroke, functional disability, and an impaired social network interact to reduce life satisfaction for the long-term survivors of stroke.

Activities of Daily Living↗

Exposure to fluorocarbons during the filling and repair of air-conditioning systems in cars--a case report.

A worker exposed to fluorocarbons in an automobile plant for seven years experienced shortness of breath (in 1977) and was referred to the hospital. The clinical examination revealed electrocardiographic abnormalities. He recovered quickly and returned to work. During the following year (1978) he suffered subarachnoid bleeding with hemiparesis, and four years later he had an operation for a thymoma. Hygienic measurements in 1980-1981 showed large variations in the fluorocarbon concentrations in the plant, the average 8-h concentrations being below the occupational exposure limit of 500 ppm but several short-time measurements reaching levels of over 750 ppm. It was suggested that, persons with heart disease do not necessarily have to be removed from work with fluorocarbons without careful review of the exposure but that the evaluation of the exposure should not only be based on time-weighted average concentrations, but also on values for brief periods, in that such concentrations can often be decreased by simple and cheap measures.

Air Conditioning↗