Studies of Cognitive Functions and the Organization of Brain Bioelectrical Activity during Waking and Sleep in Patients with Frontal Lobe Tumors

摘要

Objective. To assess impairments to cognitive functions and study the organization of brain bioelectrical activity in the sleep–waking cycle in patients with frontal lobe tumors. Materials and methods. Twenty patients of both sexes aged 48.6 ± 6.4 years and 10 healthy subjects (controls) were investigated. Group 1 included patients without neurological impairments with tumors of mean volume 8.9 ± 5.1 cm3 and group 2 included patients with signs of frontal dysfunction and mean tumor volume 40.7 ± 2.1 cm3. Impairments to cognitive functions were assessed using a battery of tests. The EEG was recorded in waking and during nocturnal sleep. Results. Degradation of cognitive functions in patients with frontal lobe tumors was accompanied by increases in power in the δ and θ ranges and cortical areactivity during waking, along with increased power in the δ, θ, and α frequency ranges and decreased activation in the REM sleep phase. Conclusions. The data obtained here may be of value in seeking markers for early signs of deterioration of cognitive functions in patients with frontal lobe tumors for prompt correction of patients’ functional status.