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TOPOGRAPHIC BRAIN MAPPING OF EMOTION-RE-

LATED HEMISPHERE ASYMMETRIES

W. Wittling and R. Roachmann Lehrstuhl fir Biopsychologie und Klinische Psychologie,

Katholische Universitat Eichstatt, D-8078 Eichstatt, F.R.G.

The study used topographic brain mapping of visual evoked

potentials to investigate emotion-related hemisphere asymme-

tries. The stimulus material consisted of color photographies

of human faces. grouped in two emotion-related categories:

normal faces (neutral stimuli) and faces deformed by derma-

tological diseases (emotional stimuli). The pictures were pre-

sented tachistoscopically to 20 adult right-handed subjects.

Brain activity was recorded by 30 EEG electrodes with linked earlobes as reference. The waveforms were averaged

separately with respect to each of the two stimulus conditions.

Statistical analysis by means of significance probability map-

ping revealed significant differences between stimulus condi-

tions for two periods of time, indicating right hemisphere

superiority in emotion-related processing. The results are

discussed in terms of a 2-stage-model of emotional processing

in the cortical hemispheres.

HEART-BRAIN INTERACTION DURING SLEEP AND

WAKEFULNESS

Christoph Wiilk and Manfred Velden

University of Osnabriick. Osnabriick. F.R.G.

In their ‘baroreceptor hypothesis’ the Laceys assume that

cardiac activity may inhibit cortical functioning, but the evi-

dence for the type of inhibition they thought of has been seriously criticized. As a revision of this hypothesis we assume

that the rhythmic neuronal activity from the baroreceptors can evoke synchronized brain electrical activity by ‘driving’

thalamic neurons into a state of resonance (EEG-alpha activ-

ity) which interferes with the transmission of afferent informa- tion to the cortex (‘cardiac driving’-theory). Hence synchroni-

sation of brain activity induced by cardiac activity is not only an indicator of an inhibition of the brain, but constitutes the

mechanism that modulates cortical functioning.

Beyond theoretical perspectives this might open a new

field of application for cardiovascular psychophysiology. Since

sleep consists of states of highly synchronized brain activity

and. as has repeatedly been reported, monotonous sensory stimulation can induce sleep, it might be possible to treat

sleeping problems by manipulating cardiac activity. Non phar-

macological treatment of sleeplessness is badly needed.

ROLE OF THE CARDIO-VASCULAR RELATED PEP- TIDES ON THE WATER HOMEOSTASIS

Hiroshi Yamashita. Hiroshi Kannan, Kiyotoshi Inenaga and

Shigeki Yamamoto

Univ. Occup. Environ. Health, Sch. Med. Kitakyushu, Japan

Recently cardio-vascular related peptides: atria1 natriuretic

peptide (ANPI, brain natriuretic peptides (BNP) and endothe-

lin (ET) were found in the brain. ANP and BNP have similar-

ity in amino acid sequence. Intracerebroventricular injection of ANP and BNP exert natriuretic, diuretic. antidipsogenic

and hypotensive effects and decrease vasopressin release. ET

induces contraction of various vascular smooth muscles and

produces systemic hypertension. Intracerebroventricular injec-

tion of ET exerts change of blood pressure, heart rate and

renal sympathetic nerve activities. Thus, ANP, BNP and ET

may directly have central action. as well as peripheral action

and may act as neurotransmitter or neuromodulator in the

CNS. Effects of ANP, BNP, ET and A 11 on neurons of

hypothalamic areas such as the supraoptic nucleus and the

regions of the anteroventral third ventricle which may be

tightly related to the water homeostasis were investigated and

compared by using rat brain slice preparations and electro-

physiological unit recording.

A FRONTO-CENTRAL NEGATIVE WAVE IN AERPs OF

CHILDREN UNDER A CHOICE-REACTION TASK

J. Yordanova, A. Angelov and V. Silyamova

Brain Research Institute, Bulg. Acad. of Sci., Sofia, Bulgaria

Auditory event-related potentials (AERPs) were registered at

F,, C, and P, in 50 normal children aged 6-l 1 years who were presented a series comprising two types of auditory stimuli -

high probability (H-1200 Hz, P = 0.75) and low probability

(L-800 Hz, P = 0.25) tones. Both types of stimuli were targets

and required fast and accurate motor reactions with the

corresponding hand (left or right).

A large negative wave with mean latency 450 ms was

found to be present in both L and H AERPs at F, and C,. It was related to stimulus probability being later and higher for

the L tone AERPs. The amplitude difference between L and H N450 was greater for younger children, N4SO is interpreted

in terms of cognitive development and AERP developmental changes.

SKELETAL MUSCLE PATTERNING DURING A NON-

VERBAL (NV) COMMUNICATION TASK

Larry D. Young

Bowman Gray Medical School. Winston-Salem, NC. U.S.A

Previous research has reported that patterns of integrated

EMG activity discriminated affective reactions to various NV

cues. In one of these studies (Englis et al.. 19X2). the results

clearly suggest that subjects were not mimicking the facial reaction of the individual they were observing. However. no

previous studies have been reported of EMG responses dur-

ing the task of decoding NV cues.