SNAPSHOTS OF NEURONAL ACTIVATION DUE TO VISUAL

AND AUDITORY STIMULI UNDER AGE, GENDER AND

NEURODEGENERATION EFFECT. HIGH- DENSITY EEG

STUDIES

ANTHOULA C. TSOLAKI, MD

NEUROLOGY CLINIC, G.H. “AGIOS PAVLOS”, THESSALONIKI, GREECE

INFORMATION TECHNOLOGIES INSTITUTE (ITI), CENTRE FOR RESEARCH & TECHNOLOGY HELLAS

10th Panhellenic Conference of Alzheimer's Disease and Related Disorders (PICAD) and

2nd Mediterranean Conference of Neurodegenerative Diseases (MeCOND)

COGNITIVE BRAIN SIGNAL PROCESSING LAB, (CBP)

Information Technologies Institute

3 Neurophysiological Studies using HD- EEG recordings

EGI 300 Geodesic EEG system (GES 300) using a 256-channel HydroCel GeodesicSensorNet (HCGSN)

Study of neuronal response in different age groups, in healthy and neurodegenerative disease.

Event related potentials MMN, P300, N400, N170

Brain source localization

HD-EEG

PROTOCOL DETAILS - EXCLUSION CRITERIA

Participants

volunteers from the Centre for Research & Technology Hellas,

the dementia outpatient clinic of the 3rd Neurology department of Aristotle University of Thessaloniki

from personal inquiry and emails in social networks

120 participants are recruited, divided in three groups: a) 30 young healthy participants aged 25-40 years old, b) 30 healthy elderly greater than 65 years old d) 30 MCI subjects and d) 30 mild AD patients aged greater than 65 years old

The study protocol has been approved by the Ethics Committee of the Centre for Research & Technology Hellas and the Ethics Committee of Aristotle University (Protocol No 69/29.12.2013)

Exclusion criteria:

any severe physical illness

current psychiatric or neurological disorder

history of drug or alcohol abuse

recent start (less than 15 days) of acethylcholinesterase inhibitors medication or other neuromodifying drugs

other types of dementia

Participants reported normal or corrected-to-normal vision and audition

Neuropsycological evaluation: MMSE , MoCA, TRAIL B, BDI, GDS, IADL, and FRSSD

Blood tests and brain MRI, qualitative EEG evaluation

Diagnosis of mild AD or mild cognitive impairment is according DSM-V criteria

1ST STUDY, HEALTHY POPULATION, AGE AND GENDER DIFFERENCE

PARTICIPANTS - PROTOCOL

27 young (14F/13M) and 18 elderly (9F/8M)

Active Two- tone oddball experiment, Standard tone (250Hz, probability 0,8), Target tone (4000Hz, probability 0,2)

All stimuli:150ms duration, 5ms rise/fall time and 75dB SPL, ISI of 2 sec

Total number of tones: 250

The subject was asked to identify the target tone by clicking the left button of the mouse with the Right hand.

RESULTS (1)

RESULTS (2)

RESULTS (3)

RESULTS (4)

MMN BA Lobe

Young 47 Frontal

Elderly 47 Frontal

P300 BA Lobe

Young 11 Frontal

Elderly 38 Temporal

N400 BA Lobe

Young 11 Frontal

Elderly 11 Frontal

2ND STUDY, AGE EFFECT IN EMOTIONAL PROCESSING, HEALTHY

POPULATION

PARTICIPANTS

Ηealthy female (11 young (25-40 years old) and 11 elderly (>60 years old))

right-handed volunteers Α subgroup of the sample recruited for the project CBP: Cognitive Brain Signal

Processing Lab (Kosmidou et al., 2014).

Νormal or corrected-to-normal vision and audition.

Νeuropsychological evaluation -blood tests - brain MRI

All participants with depression (BDI >9/63 score, and GDS >4/15) were excluded,

Participants provided written informed consent.

PROTOCOL

RESULTS

Anger Fear

latency

(ms)

amplitude (μV) latency

(ms)

amplitude (μV)

Young 156 -2.02a 156 -1.84a

Elderly 168 -6.13a 176 -4.68a

RESULTS (2)

RESULTS (3)

ID Location Intensity

(nA)

BA Gyri Lobe

Anger

Young 576 (-45, 45, -13) 0.30 47 Inferior Frontal Frontal

Elderly 191 (-10, 31,-27) 0.30 11 Rectal Frontal

Fear

Young 38 (-31, 17, -41) 0.33 38 Superior Temporal Temporal

Elderly 38 (-31, 17, -41) 0.34 38 Superior Temporal Temporal

RESULTS (4)

ID Location Intensity

(nA)

BA Gyri Lobe

Young vs

Elderly

Anger 24 (18, 3, -41) 0.18 36 Uncus Limbic

Fear 5 (32, -11,-41) 0.28 20 Uncus Limbic

3RD STUDY, AUDIO ERPS IN HEALTHY, MCI & AD

Brain source localization of MMN and P300 ERPs in Mild

Cognitive Impairment and Alzheimer's disease: A High Density

EEG approach

Anthoula C. Tsolaki, Vasiliki Kosmidou, Ioannis (Yiannis) Kompatsiaris, Chrysa Papadaniil, Leontios Hadjileontiadis,

Katerina Adam,Magda Tsolaki.

Under Revision in Neurobiology of Aging

PARTICIPANTS

Group # of Participants (Female/Male) Age (years) MMSE score Education level (years) Error on standard tone Error on target tone Response time (ms)

Control21 (13/8) 67 (±2.7) 28.81*

(±0.9)

14** (±5) 0.50 (±0.19) 1.02* (±0.26) 645 (±71)

MCI21 (14/7) 72 (±4.7) 27* (±1.4) 10 (±5) 1.01 (±1.4) 9.32* (±24.95) 667 (±253)

AD21 (14/7) 70 (±6.8) 22.6* (±3.4) 8 (±6) 2.5* (±2.31) 22.56* (±22.78) 957* (±162)

*p<0.005, **p<0.01, no super-script indicates no statistical significance between the groups

PROTOCOL

Active Two- tone oddball experiment, Standard tone (250Hz, probability 0,8), Target

tone (4000Hz, probability 0,2)

All stimuli:150ms duration, 5ms rise/fall time and 75dB SPL, ISI of 2 sec

Total number of tones: 250

The subject was asked to identify the target tone by clicking the left button of the

mouse with the Right hand.

RESULTS

MMN P300

RESULTS (2)

ID Location Intensity

(nA)

Brodmann

Area

Gyri Lobe

P300

Control 40 (39,17,-41) 0.13 38 Superior Temporal Temporal

MCI 603 (39, 59,-13) 0.14 11 Middle Frontal Frontal

AD 603 (39,59,-13) 0.18 11 Middle Frontal Frontal

ID Location Intensity

(nA)

Brodmann

Area

Gyri Lobe

MMN

Control 189 (4,24,-27) 0.11 11 Rectal Frontal

MCI 595 (-38,59,-13) 0.14 11 Middle Frontal Frontal

AD 240 (25,-39,-20) 0.12 37 Fusiform Gyrus Temporal

RESULTS (3)

MMN P300

CONCLUSIONS

Brain source localization is achieved with high density EEG

Results reveal changes in N170 with aging for two negative emotional stimuli

Differences in brain neural activation at the ‘anger’ and ‘fear’ face processing

Higher negativity in the occipito-temporal electrode sites in case of elderly

Aging appears to affect the limbic area neural activation at emotional processing

Brain source localization of ERPs is proposed as prognostic tool in neurodegeneration.

Early change of neuronal activation is revealed even in preclinical stages.

Frontal lobe is revealed to play an important role both in MCI and AD.

Group- based Results

ACKNOWLEDGMENTS

This work was funded by the GSRT Research Excellent Grant ARISTEIA,

within the 4th Strategic Objective of the operational program “Education

and Lifelong Learning” entitled ‘Supporting the Human Capital in order

Promote Research and Innovation’, under grant agreement 440

Dr. Vasiliki Kosmidou,

Post-doctoral Researcher

Information Technologies Institute

(ITI), Centre for Research &

Technology Hellas

Dr. Chrysa Papadanii,Department of Electrical & Computer Engineering, AristotleUniversity of Thessaloniki.Doctoral grant- holder

Katerina Adam,

Information Technologies Institute

(ITI), Centre for Research &

Technology Hellas

Dr. Ioannis (Yiannis) KompatsiarisResearcher A,

Information Technologies Institute

(ITI), Centre for Research &

Technology Hellas

Dr. Leontios Hadjileontiadis,

Professor of Department of Electrical& Computer Engineering, AristotleUniversity of Thessaloniki.& Department of Electrical and Computer Engineering, KhalifaUniversity, PO BOX 127788, AbuDhabi, UAE.

Dr. Magdalini Tsolaki

Professor of Neurology,

3rd Department of Neurology,

Aristotle University of Thessaloniki

Pressident og Panhellenic Federation

of Alzheimer’s Disease

SPECIAL THANKS

Thank you for your attention!