Abnormalities in auditory and visual cognitive processes are differentiated with theta responses in patients with Parkinson's disease with and without dementia

Are there consistent abnormalities in event‐related EEG oscillations in patients with Alzheimer’s disease compared to other diseases belonging to dementia?

“…Furthermore, theta phase-locking was lower in PDMCI (but not ADMCI) than in CU participants (Yener et al, 2019). Similarly, Güntekin et al (2020) reported that event-related theta power and phase locking during a visual and auditory oddball tasks were lower in PDD than PDMCI patients and lower in PDMCI patients than PD patients without cognitive deficits and controls. Concerning cerebrovascular disease, Xu et al ( 2015) reported that event-related measures of interdependence of theta rhythms at parieto-occipital electrode pairs during a visual oddball paradigm were lower in major VCI patients as compared to CU adults.…”

“…Similarly, Güntekin et al. (2020) reported that event‐related theta power and phase locking during a visual and auditory oddball tasks were lower in PDD than PDMCI patients and lower in PDMCI patients than PD patients without cognitive deficits and controls.…”

“…Notably, these effects were not demonstrated at the individual level. Furthermore, they may be disease unspecific as similar abnormalities were observed in PDMCI (Güntekin et al, 2020;Yener et al, 2019), PDD (Güntekin et al, 2020), LBD (Rosenblum et al, 2020), and major VCI patients (Lou et al, 2011;Wang et al, 2016;Xu et al, 2011Xu et al, , 2015. Keeping the above data in mind, the present Expert Panel recommends that eventrelated delta and theta power during oddball tasks may be used in future clinical trials carried out in ADMCI and ADD patients for analyses at the group level.…”

“…Furthermore, some markers of event-related theta responses (particularly event-related power) were lower in ADMCI and ADD patients compared to CU adults (Başar et al, 2010;Caravaglios et al, 2010;Güntekin et al, 2008;Tülay et al, 2020;Yener et al, 2007). However, these effects may be non-specific as similar changes were observed in PDMCI (Güntekin et al, 2020;Yener et al, 2019), PDD (Güntekin et al, 2020), LBD (Rosenblum et al, 2020), and major VCI patients (Lou et al, 2011;Wang et al, 2016;Xu et al, 2011Xu et al, , 2015. Future comprehensive EEG experiments are therefore needed to compare event-related delta and theta responses among patients with different dementias at different levels of cognitive deficits.…”

Special Report on the Impact of the COVID-19 Pandemic on Clinical EEG and Research and Consensus Recommendations for the Safe Use of EEG

“…[111][112][113] Overall, reductions of delta and theta responses are thought to be a general indicator of pathological brains; reductions of these EEG bands are found not just found in schizophrenia and bipolar patients but also in dementia patients. Patients with MCI, 114,115 patients with Alzheimer's disease, 116,117 and dementia patients with Parkinson's disease 118,119 have also been shown to exhibit reduced delta and theta responses. Similar to those with schizophrenia, bipolar disorder patients have reduced auditory steady-state gamma power.…”