Biomedical subjects

T Elbert

Publications and source records attributed to T Elbert.

147 records · Page 9Linked to original sources

PubMedDate not supplied

Biofeedback produced slow brain potentials and task performance.

Twenty subjects learned to control slow potential (SP) shifts of the brain by means of a biofeedback procedure. Depending upon the pitch of a signal tone, negative SP shifts had to be increased or reduced during intervals of 6 sec each. Visual feedback of the actual SP shift was given. Blocks of training trials alternated with blocks of test trials without any feedback of the SPs. At the end of every test trial a simple arithmetic problem had to be solved by the subjects. Subjects performed the computation in a shorter time interval if an increased negativity preceded task onset as compared to slower response times during suppression of negativity. Results suggest that cortical negativity reflects unspecific preparation for cerebral performance.

Attention↗

PubMedDate not supplied

Psychophysiology of arterial baroreceptors and the etiology of hypertension.

Arterial baroreceptors are sensitive to blood pressure dependent blood vessel dilation. They play a key role in the short term regulation of blood pressure. Their impact on psychological and psychophysiological aspects is of increasing interest. The review focuses on experimental techniques for the controlled baroreceptor manipulation. Results from the application of these techniques show that baroreceptor activation influences the cardiovascular system as well as central nervous functioning: Behavioral and electrophysiological measures of arousal, low level reflexes and pain responses are modulated through baroreceptor manipulation. The observation of an overall dampening ('barbiturate like') effect of baroreceptor activity led Dworkin et al. formulate the theory of learned hypertension: Subjects might experience blood pressure dependent baroreceptor activation as stress and pain relieving. High blood pressure periods become negatively reinforced. Phasic high blood pressure might develop as a coping strategy. Data from a longitudinal human study supporting this theory are reported.

Arousal↗

PubMedDate not supplied

Study of the human auditory cortices using a whole-head magnetometer: left vs. right hemisphere and ipsilateral vs. contralateral stimulation.

Structural and functional asymmetries of the temporal lobe affect language development and may also play a role in a variety of disorders, ranging from specific language impairment to schizophrenia. Whole-head neuromagnetometers allow the noninvasive measurement of functional asymmetries since activity from both hemispheres is recorded simultaneously. In the present study, the location of the auditory cortices and their responsiveness to pure tones was compared between hemispheres in healthy human subjects. Data suggest a greater contralateral than ipsilateral activation. In line with previous findings, sources of responses for the right hemisphere seem to be more anterior than for the left one.

Acoustic Stimulation↗