Functional responses of the human brain studied by regional cerebral blood flow techniques
Ingvar, D.H.
Acta Clinica Belgica 32(2): 68-83
1977
ISSN/ISBN: 1784-3286 PMID: 899603 Document Number: 120984
Measurements of regional cerebral blood flow (rCBF) by means of the 133Xe clearance technique show that the activity in the normal resting brain has a typical distribution with the highest activities in the premotor and frontal regions and the lowest in the temporal and parietal ones. This resting pattern is readily changed by voluntary motor activity which gives a rolandic-postrolandic activity peak, and by sensory stimulation which activates rolanic prerolandic structures especially. Speech and reading activate the upper, anterior and posterior speech cortices, as well as the face, tongue and month area. Problem solving also activates premotor and frontal regions especially and, if visual activity is involved, also the occipital poles. These normal patterns by and large confirm well known aspects of the functional anatomy of the human dominant hemisphere. A number of clinical correlations have been established between rCBF abnormalities and focal brain lesions caused by cerebral vascular disorders, head trauma, brain tumors, epilepsy and infectious diseases. In many such disorders, the above mentioned activation patterns are absent, a fact often to be expected from the clinical symptomatology. Patients with organic dementia show a reduced flow level, grossly in proportion to the intellectual deficit.