Акустические стволовые и когнитивные вызванные потенциалы при хроническом нарушении мозгового кровообращения

Abstract

Current research aimed to investigate informational content of auditory evoked potentials (EP) (acoustic brainstem and cognitive – mismatch negativity) in assessment of brain functional status and cognitive functions in patients with chronic cerebrovascular disease (chronic CVD). Clinical and neurophysiological examination was performed for 33 patients. Group 1 included 12 patients with chronic CVD in carotid circulation, mean age 61,2 ± 6,3 years old; group 2 included 11 patients with chronic CVD in vertebrobasilar circulation, mean age 62,4 ± 8,0 years old; group 3 (control) - 10 patients without cerebrovascular diseases), mean age 54,6±6,4 years old. For registration of acoustic brainstem EP two series of 1000 stimuli were applied (“click” type, duration 0,1 ms, intensity 65 dB above patient’s hearing level, frequency 10 Hz). Mismatch negativity (MMN) was registered in classic odd-ball paradigm (standard stimulus – a sinusoidal tone with 1000 Hz frequency, deviant – with 900 Hz frequency; interstimulus interval – 500 ms). Results. According to results of MMSE, FAB, test of 10 words repetition and Schulte tables patients with chronic CVD, independently of predominantly affected vascular pool, demonstrated cognitive impairment as compared to control group. In patients with chronic CVD no statistically significant differences of acoustic brainstem EP were revealed, however, MMN amplitude was decreased in comparison with control group. It indicates a shortened lifetime of memory traces and deficit in involuntary attention switching in chronic CVD. Investigation of cognitive EP MMN is informative and can be used in assessment of cognitive impairment.