The visual cognitive network, but not the visual sensory network, is affected in amnestic mild cognitive impairment: A study of brain oscillatory responses

Yener, Görsev; Emek‐Savaş, Derya Durusu; Güntekin, Bahar; Başar, Erol

doi:10.1016/j.brainres.2014.08.038

Cited by 18 publications

(20 citation statements)

References 47 publications

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“…Our results indicated significant and diverse differences between AD patients and healthy controls, implying a separation of sensory and cognitive gamma response-related circuits in AD. Our earlier work on the delta band range in AD ( Yener and Başar, 2010 ) and MCI ( Yener et al, 2014 ) also demonstrated the involvement and separation of sensory and cognitive circuits in AD/MCI.…”

Section: Discussionmentioning

confidence: 79%

Delay of cognitive gamma responses in Alzheimer's disease

Başar

Emek‐Savaş

Güntekin

et al. 2016

NeuroImage: Clinical

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Event-related oscillations (EROs) reflect cognitive brain dynamics, while sensory-evoked oscillations (SEOs) reflect sensory activities. Previous reports from our lab have shown that those with Alzheimer's disease (AD) or mild cognitive impairment (MCI) have decreased activity and/or coherence in delta, theta, alpha and beta cognitive responses. In the current study, we investigated gamma responses in visual SEO and ERO in 15 patients with AD and in 15 age-, gender- and education-matched healthy controls. The following parameters were analyzed over the parietal-occipital regions in both groups: (i) latency of the maximum gamma response over a 0–800 ms time window; (ii) the maximum peak-to-peak amplitudes for each participant's averaged SEO and ERO gamma responses in 3 frequency ranges (25–30, 30–35, 40–48 Hz); and (iii) the maximum peak-to-peak amplitudes for each participant's averaged SEO and ERO gamma responses over a 0–800 ms time block containing four divided time windows (0–200, 200–400, 400–600, and 600–800 ms). There were main group effects in terms of both latency and peak-to-peak amplitudes of gamma ERO. However, peak-to-peak gamma ERO amplitude differences became noticeable only when the time block was divided into four time windows. SEO amplitudes in the 25–30 Hz frequency range of the 0–200 ms time window over the left hemisphere were greater in the healthy controls than in those with AD. Gamma target ERO latency was delayed up to 138 ms in AD patients when compared to healthy controls. This finding may be an effect of lagged neural signaling in cognitive circuits, which is reflected by the delayed gamma responses in those with AD. Based on the results of this study, we propose that gamma responses should be examined in a more detailed fashion using multiple frequency and time windows.

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Section: Discussionmentioning

confidence: 79%

Delay of cognitive gamma responses in Alzheimer's disease

Başar

Emek‐Savaş

Güntekin

et al. 2016

NeuroImage: Clinical

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“…Pain modulates both cortical responses to external stimuli and internal events [ 17 , 19 , 45 , 46 ], and consequently is related to nociceptive events, but also to cognitive and psychological processes. Cognitive dysfunction is frequently observed in individuals with chronic pain [ 47 , 48 ], and correlated to decreased EEG responses to auditory [ 49 ] and visual [ 50 ] stimuli. As it is not commonly considered as a primary outcome measure in pain studies, cognitive dysfunction may represent a confounding factor, being the true source for diminished evoked potentials.…”

Section: Discussionmentioning

confidence: 99%

Electroencephalographic Patterns in Chronic Pain: A Systematic Review of the Literature

et al. 2016

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The main objective of this study is to review and summarize recent findings on electroencephalographic patterns in individuals with chronic pain. We also discuss recent advances in the use of quantitative Electroencephalography (qEEG) for the assessment of pathophysiology and biopsychosocial factors involved in its maintenance over time. Data collection took place from February 2014 to July 2015 in PubMed, SciELO and PEDro databases. Data from cross-sectional studies and longitudinal studies, as well as clinical trials involving chronic pain participants were incorporated into the final analysis. Our primary findings related to chronic pain were an increase of theta and alpha EEG power at rest, and a decrease in the amplitude of evoked potentials after sensory stimulation and cognitive tasks. This review suggests that qEEG could be considered as a simple and objective tool for the study of brain mechanisms involved in chronic pain, as well as for identifying the specific characteristics of chronic pain condition. In addition, results show that qEEG probably is a relevant outcome measure for assessing changes in therapeutic studies.

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“…Recently, cognitive ERP studies have gained popularity for understanding and revealing dementive disorders (Frodl et al, 2002 ; Polich and Corey-Bloom, 2005 ; Jackson and Snyder, 2008 ; Papaliagkas et al, 2008 , 2011 ; Lai et al, 2010 ; Missonnier et al, 2010 ; Laskaris et al, 2012 ), since they can target at specific mental faculties (the same that are scrutinized via neuropsychological screening) with the additional advantage of leading to directly quantifiable indices. Among the possible experimental designs (Olichney et al, 2002 ; Güntekin et al, 2013 ; Gozke et al, in press ), the standard auditory oddball stimulus paradigm for Audiroty Event Related Potentials (AERPs) is the simplest to perform. After averaging the brain responses from the AERPs when targeting auditory tones, two of the main morphological components (known as N200 and P300 based on their polarity and latency) appear deteriorated in the case of MCI patients (Ritter et al, 1984 ; Golob et al, 2001 ).…”

Section: Introductionmentioning

confidence: 99%

A novel biomarker of amnestic MCI based on dynamic cross-frequency coupling patterns during cognitive brain responses

et al. 2015

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The detection of mild cognitive impairment (MCI), the transitional stage between normal cognitive changes of aging and the cognitive decline caused by AD, is of paramount clinical importance, since MCI patients are at increased risk of progressing into AD. Electroencephalographic (EEG) alterations in the spectral content of brainwaves and connectivity at resting state have been associated with early-stage AD. Recently, cognitive event-related potentials (ERPs) have entered into the picture as an easy to perform screening test. Motivated by the recent findings about the role of cross-frequency coupling (CFC) in cognition, we introduce a relevant methodological approach for detecting MCI based on cognitive responses from a standard auditory oddball paradigm. By using the single trial signals recorded at Pz sensor and comparing the responses to target and non-target stimuli, we first demonstrate that increased CFC is associated with the cognitive task. Then, considering the dynamic character of CFC, we identify instances during which the coupling between particular pairs of brainwave frequencies carries sufficient information for discriminating between normal subjects and patients with MCI. In this way, we form a multiparametric signature of impaired cognition. The new composite biomarker was tested using data from a cohort that consists of 25 amnestic MCI patients and 15 age-matched controls. Standard machine-learning algorithms were employed so as to implement the binary classification task. Based on leave-one-out cross-validation, the measured classification rate was found reaching very high levels (95%). Our approach compares favorably with the traditional alternative of using the morphology of averaged ERP response to make the diagnosis and the usage of features from spectro-temporal analysis of single-trial responses. This further indicates that task-related CFC measurements can provide invaluable analytics in AD diagnosis and prognosis.

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The visual cognitive network, but not the visual sensory network, is affected in amnestic mild cognitive impairment: A study of brain oscillatory responses

Cited by 18 publications

References 47 publications

Delay of cognitive gamma responses in Alzheimer's disease

Delay of cognitive gamma responses in Alzheimer's disease

Electroencephalographic Patterns in Chronic Pain: A Systematic Review of the Literature

A novel biomarker of amnestic MCI based on dynamic cross-frequency coupling patterns during cognitive brain responses

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