Slowed cognitive processing and high workload in Parkinson's disease

Event-Related Desynchronization/Synchronization During Discrimination Task Conditions in Patients with Parkinson’s Disease

“…Alterations of the basal ganglia with proven neuronal degenerative disorders of dopaminergic neurons and a reduction in activity in frontostriatal neural circuitry, are suggested to play a role in the executive dysfunction of PD (Taylor et al 1990;Innis et al 1993;Lewis et al 2003;Owen 2004;Leblois et al 2006;Anik et al 2007). The slowed information processing, insufficient encoding strategies and planning, attentional set-shifting are related to memory deficits and cognitive impairment in PD (Daum et al 1995;Pillon et al 1997;Knoke et al 1998;Robertson and Empson 1999;Sawamoto et al 2002;Cools 2006). The primary working memory deficit in PD is associated by Higginson et al 2003, with impaired free recall performances.…”

“…ERP investigations have shown P3 mainly prolonged latencies and/or diminished amplitudes for Parkinsonian patients (PP) when compared to control subjects (CS) (Evarts et al 1981;Tachibana et al 1992;Philipova et al 1997;Wascher et al 1997;Minamoto et al 2001;Antal et al 2002;Wang et al 2002). Such results have been interpreted as electrophysiological signs of cognitive slowing with respect to stimulus classification and attentional processing (Robertson and Empson 1999). In the ERP method, however, the functional significance of the responses in different frequency bands is lost.…”

Brain Event - Related Oscillations in Parkinsonian Patients During Discrimination Task Conditions

“…Alterations of the basal ganglia with proven neuronal degenerative disorders of dopaminergic neurons and a reduction in activity in frontostriatal neural circuitry have been suggested to play a role in the executive dysfunction of PD (Taylor et al, 1990;Innis et al, 1993;Lewis et al, 2003;Owen, 2004;Leblois et al, 2006;Anik et al, 2007). The slowed information processing, insufficient encoding strategies and planning, and attentional setshifting are related to memory deficits and cognitive impairment in PD (Daum et al, 1995;Pillon et al, 1997;Knoke et al, 1998;Robertson & Empson, 1999;Sawamoto et al, 2002;Cools, 2006). Neuropsychological studies of PD patients report cognitive deficits even during the early stages of the disease (van Spaendonck et al, 2006).…”

“…ERP investigations have shown P3 predominantly with prolonged latencies and/or diminished amplitudes for Parkinsonian patients (PP) when compared to healthy subjects (HS) (Evarts et al, 1981;Tachibana et al, 1992;Philipova et al, 1997;Wascher et al, 1997;Minamoto et al, 2001;Antal et al, 2002;Wang et al, 2002). Such results have been interpreted as electrophysiological signs of cognitive slowing with respect to stimulus classification and attentional processing (Robertson & Empson, 1999). One valuable means of assessing deviations from the normal state in PD is to study oscillatory brain processes.…”

Beta and gamma frequency-range abnormalities in parkinsonian patients under cognitive sensorimotor task

“…The alterations of the basal ganglia with proven neuronal degenerative disorders of dopaminergic neurons and a reduction in activity in frontostriatal neural circuitry play a role in these executive dysfunctions of PD [1,2]. The disease is also characterized by slowed information processing, insufficient encoding strategies and planning, attentional set-shifting, which are related to memory deficits and cognitive impairment [3][4][5][6][7][8]. Neuropsychological studies of PD patients report cognitive deficits even during the early stages of the disease [9].…”