Avtor/Urednik		Korošec, Marko
Naslov		Potencial pripravljenosti pri ekstenziji kazalca in mežikanju
Tip		monografija
Kraj izdaje		Ljubljana
Založnik		Medicinska fakulteta
Leto izdaje		2000
Obseg		str. 45
Jezik		slo
Abstrakt		Bereitschaftspotential (BP) or readiness potential belongs to the group of movement-related cortical potentials, which occur before, during or after the motor activity. With BP we studied the central neuronal mechanisms involved in preparation and initiation of voluntary blinking in 31 normal subjects and 6 patients with blepharospasm. Our hypothesis was that in normal subjects there is a slowly rising BP-related electroencephalographic negativity also before voluntary blinking. Our aim was to compare the BP of voluntary blinking (BPblink) with a classical BP elicited by index finger extension; to define reference values for BPblink latency and amplitude; and to describe the topography of BPblink. As patients with extrapyramidal diseases often present with an impairment of eye movements and blinking, we performed recordings also in a group of patients with blepharospasm. Our results confirmed the presence of blink-related BP in normal subjects. Both BPblink and BPhand consisted of an early and a late component and had a similar onset-latency and the highest amplitude over the vertex. However, compared to BPhand the absolute amplitude of BPblink was lower and it did not show lateralization. Our results showed a high variability in BPblink and in BPhand latencies and amplitudes, making a set-up of reference values impractical. In a group of six patients with blepharospasm, BPhand was found in all of the patients and BPblink in only one. Possible reasons for absent BPblink in our patients with blepharospasm include a disease-related impairment of mechanism for voluntary blink preparation and execution as well as inadequacies of recording technique (insufficiently defined electromyographic activity; contamination of records with artefacts). (Abstract truncated at 2000 characters.)
Deskriptorji		CONTINGENT NEGATIVE VARIATION BLEPHAROSPASM BLINKING BASAL GANGLIA DISEASES MOTOR ACTIVITY ACTION POTENTIALS ELECTROENCEPHALOGRAPHY ELECTROMYOGRAPHY