Poster ID

Department Name of

Presenting Author

Designation Abstract Title Authors

MSc-4 Physiology Anchal Singh

MSc. Student

Graded distal supra-systolic occlusion

differentially modulates the flow velocity and shear components in

radial artery

Singh Anchal, Chandran S Dinu,

Jaryal K Ashok, Joshi Deepak, Deepak KK

MSc-6 Physiology Manorma

Saini MSc.

Student

Cortical sources of verbal “OM” chanting: A qEEG

study

Saini Manorma, Samanchi Rupesh,

Muthukrishnan Prakash Suriya, Kaur

Simran,Sharma Ratna, Tayade Prashant

MSc-25 Physiology Kanishka MSc.

Student

Shortening of EEG microstates of

perceptual reversals of emotional stimuli in schizophrenia during

binocular rivalry

Kanishka, Suriya Prakash

Muthukrishnan, Angel Anna Zacharia, Rupesh

Samanchi, Sunaina Soni, Navdeep Ahuja,

Prashant Tayade, Simran Kaur, Mamta Sood, Ratna Sharma

MSc-32 Physiology Ankit Gurjar

MSc. Student

Cortical processing of visuospatial complex Hindi words: A QEEG

study

Ankit, Samanchi Rupesh, Kaur Simran, Muthukrishnan Suriya

Prakash, Sharma Ratna, Prashant

Tayade

MSc-24 Physiology

Dr Garima Sharma

MSc. Student

Effect of rTMS therapy on pain status, thermal sensitivity in Myofacial

Pain Dysfunction syndrome

Sharma G, Arya S, Gupta S, Bhatia R

MSc-4

Graded distal supra-systolic occlusion differentially modulates the flow velocity and

shear components in radial artery

Authors: Singh Anchal1, Chandran S Dinu2, Jaryal K Ashok3, Joshi Deepak4, Deepak KK5

1 M.Sc. student,

2 Assistant Professor,

3 Professor,

4 Assistant Professor,

5 Professor and Head

Department of Physiology, AIIMS, New Delhi

Centre for biomedical Engineering IIT- Delhi

Presenting Author: Anchal Singh

Email: aanchalsingh1702@gmail.com

Corresponding Author: Dinu S Chandran

Email: dinuschandran@gmail.com

Introduction: Supra-systolic occlusion of radial artery at different occlusion pressures are

being used to induce low flow mediated constriction (LFMC) for assessment of resting

endothelial function. Occlusion induced reduction in anterograde shear rate has been

considered to be the stimulus responsible for LFMC response. We hypothesised that

occlusion induced alteration in the luminal shear rate will differ according to the grade of

supra-systolic occlusion imposed.

Aims & Objectives: Aim of the study was to examine the effect of graded supra-systolic

occlusion on flow velocity and shear profile in radial artery. The objective was to record the

changes in anterograde, retrograde flow velocities and shear rates along with oscillatory shear

index (OSI) in response tograded supra-systolic occlusion.

Materials and methods: We examined 19 healthy volunteers (27±3 yrs) who reported to the

laboratory after an overnight fast. Subjects quietly rested in the supine position for 20 min

following which blood pressure of the subject was measured using sphygmomanometry.

Radial artery was imaged in upper forearm using a high frequency (10 MHz) linear array

probe to simultaneously acquire blood flow velocities and diameters in duplex mode. After

baseline recording of 1 minute, the pneumatic occlusion cuff applied to distal forearm was

inflated to three different grades of pressures 25, 50 and 100 mmHg above the systolic blood

pressure of the subject for 5 min in a sequential manner to induce LFMC of radial artery.The

order of application of pressure was randomised across subjects and an interval of 30 minutes

was observed between application of each occlusion pressure in every subject. Radial artery

blood flow velocities and diameters were acquired during the phase of occlusion and a repeat

baseline recording was performed before application of occlusion at a different grade of

pressure.Shear rates and OSI were calculated using standard formula reported in the

literature.

Results: Cuff inflation resulted in significant decrease in anterograde flow velocities and

shear rate and a significant increase in retrograde flow velocities and shear rate at all grades

of occlusion in comparison to respective baseline values. % reduction in anterograde shear

rate was significantly higher at 100 mmHg occlusion in comparison to 25 mmHg (28.78 ±

23.02 vs 12.90 ± 20.39; p < 0.05) The change in retrograde shear rate from baseline peaked at

25 mmHg occlusion (-29.313 ± 12.705) and showed a statistically significant stepwise

decrement at higher grades of occlusion (-20.997 ± 6.491 at 50 mmHg and -16.139 ± 5.360 at

100 mmHg; p<0.05 for all comparisons). Occlusion resulted in a significant rise in OSI over

baseline at all grades of occlusion. Delta change in OSI followed a similar pattern as that of

retrograde shear.

Conclusion: Besides producing reduction in anterograde flow and shear, graded

suprasystolic occlusion also induces a rise in retrograde shear rate and OSI which appear to

vary inversely with increasing grades of occlusion pressure. Therefore, quantification of

resting endothelial function by LFMC may be influenced by the grade of distal suprasystolic

occlusion pressure applied to induce the low flow state.

MSc-6

Cortical sources of verbal “OM” chanting: A qEEG study

Saini Manorma1, Samanchi Rupesh1, Muthukrishnan Prakash Suriya1, Kaur Simran1,Sharma Ratna1,

Tayade Prashant1

1Department of Physiology, All India Institute of Medical Sciences, New Delhi

Presenting Author:

Name- Manorma Saini

Email- manormasaini94@gmail.com

Corresponding Author:

Name- Prashant Tayade

Email- dr.prashanttayade@gmail.com

Background: Meditation is a process of self- regulating the mind and body. “OM” mantra is the most

widely used meditation practice in India.It has been reported in the literature that the effects of

meditation in different types of sessions of “OM” chanting like mental repetition of “OM” or a

neutral word “ONE”, listening to sound “OM”, meaningful word like “AAM” or non-meaningful word

“TOM”, produces different effects in both naïve subjects and experienced meditators. Though,

reports have been published pertaining to relaxation effect and the cortical areas activated/

deactivated during “OM” chanting using fMRI and PET scan but no study has reported using qEEG. As

qEEG provides high spatial and temporal resolution, there is a need to know the cortical sourcesof

verbal “OM” chanting assessed by qEEG.

Objectives: To study and compare the pre and post effect of verbal “OM” chanting on cortical

sources as assessed by qEEG.

Methods: A paradigm was designed using E- prime for verbal chanting of “OM” and administered in

20 healthy male subjects with a mean age of 27.5 ± 7.5 yrs. EEG was recorded using a 128-channel

geodesic sensor net. Before analysis, the data was pre-processed in which EEG signals were band-

pass filtered in 1-70 Hz and with notch filter of 50 Hz. Then eyes closed pre and post verbal to “OM”

chanting 20 seconds data was segmented followed by the artifact detection and bad channel

replacement. After pre- processing, independent component analysis was performed followed by

the source analysis using sLORETA.

Results: The post-verbal “OM” chanting when compared with the pre- verbal “OM” chanting showed

significant activation (at threshold= 0.163 and p= 0.04) in the following areas- inferior frontal gyrus,

inferior occipital gyrus, inferior temporal gyrus, insula, lingual gyrus, cuneus, extranuclear, fusiform

gyrus, medial frontal gyrus, middle frontal gyrus, middle frontal gyrus, middle occipital gyrus, middle

temporal gyrus, parahippocampal gyrus, sub- gyral, superior frontal gyrus, superior frontal gyrus,

superior temporal gyrus, uncus, angular gyrus, anterior cingulate gyrus, superior parietal lobule,

inferior parietal lobule, paracentral lobule, postcentral gyrus, post cingulate gyrus, precentral gyrus,

precuneus, superior occipital gyrus, supramarginal gyrus, transverse temporal gyrus and cingulate

gyrus.

Conclusion:Post-verbal “OM” chanting showed activation in the corticalareas which are involved in

resting state networks (RSNs).These resting state networks include frontoparietal control network

(FPCN), dorsal attentional network (DAN), ventral attentional network (VAN) and default model

network (DMN). Whereas, FPCN activation reflects the flexible switching between the DAN

(sustained attention), VAN (attention re-allocation) and DMN (mind wandering).

Keywords: qEEG, Source analysis, sLORETA, RSNs, FPCN, DAN, VAN, DMN

MSc-25

Shortening of EEG microstates of perceptual reversals of emotional stimuli in

schizophrenia during binocular rivalry

Kanishka1, Suriya Prakash Muthukrishnan

1, Angel Anna Zacharia

1, Rupesh Samanchi

1,

Sunaina Soni1, Navdeep Ahuja

1, Prashant Tayade

1, Simran Kaur

1, Mamta Sood

2, Ratna

Sharma1

1Stress and Cognitive Electroimaging Laboratory, Department of Physiology, AIIMS, New

Delhi

2Professor, Department of Psychiatry, AIIMS, New Delhi

Email ID of presenting author: kvkanishka17@gmail.com (M.Sc. Student)

Corresponding author: Dr Ratna Sharma, Professor, Department of Physiology, AIIMS, New

Delhi.

Background:Emotional deficits have been reported in patients with Schizophrenia. These

deficits may also be present in the form of negativity bias, though the neural mechanisms

allowing such alternations of perception in schizophrenia remains unexplored. Binocular

Rivalry can be used as a tool to study the neural mechanisms in terms of microstates during

perceptual reversals in schizophrenia. The study of microstates using this paradigm may help

understand if any particular microstate preferentially results in perceptual reversals of a

specific valance. The reduced or increased occurrence of microstates may be associated with

schizophrenia and its prodromal symptoms.

Objectives: The present study investigates the EEG microstates of perceptual reversals of

emotional stimuli during binocular rivalry in schizophrenia.

Material and Methods: Twenty right handed patients with Schizophrenia (mean age =31.5

yrs) performed an intermittent binocular rivalry paradigm designed using emotional and

neutral pictures by International Affective Picture System. The paradigm consisted of

presentation of three types of trials i.e., positive vs neutral, negative vs neutral and negative

vs positive pictures. Predominance ratio was calculated for each percept (750 trials per

subject). Microstate analysis was done in cartool software. EEG segments during 100msec

before response during binocular rivalry task was extracted. Two template maps were chosen

based on their high global explained variance which were fitted onto the EEG data of 20

subjects. Analysis was done for approximately 750 trials for each of the 20 patients. Further

the comparison of microstate map parameters was done for the two kinds of groups i.e., high

and low Perceptual reversals(PR) groups which were found during behavioral analysis after

the k-means clustering. Group differences for microstate parameters were assessed using K-S

normality test. In case of significant results, post-hoc pairwise comparisons between groups

were conducted using Mann-Whitney U test. Statistical analysis was carried out using SPSS

version 20.0.

Result:Out of the two microstates obtained during perceptual reversals, mean duration of

map 1 was significantly lower in patients with high rates of perceptual reversals in negative

vs neutral condition and in positive vs neutral category. Global explained variance for map 2

was higher in high PR group in positive vs negative category.

Conclusion: In schizophrenia patients with high perceptual reversals, shortening of

microstates during perceptual reversals could be associated with disruption of the neural

network activities that underlie this specific microstate leading to premature termination of

specific microstates. The shortening of the microstates in different stimulus conditions

suggests that valence has an effect on the microstate topography. Specific microstate

variables in patients with schizophrenia could be used as a marker for negativity bias in these

patients.

Key Words: Schizophrenia, Binocular rivalry, Valence, Microstates

Total Word count:441

MSc-32

Title: Cortical processing of visuospatial complex Hindi words: A QEEG study

Ankit1,

SamanchiRupesh2,KaurSimran

3, Muthukrishnan SuriyaPrakash

4,SharmaRatna

5,

Prashant Tayade6*

Affiliation: Stress and Cognition Electroimaging Lab (SCEL), Department of Physiology, All

India Institute of Medical Sciences, New Delhi

Presenting author:Ankit

Email address:ankitgurjar854@gmail.com

Corresponding Author: - Dr Prashant Tayade

Email address:dr.prashanttayade@gmail.com

Abstract Background: Hindi language which is the most commonly used language in Indian

subcontinent follows alphasyllabary writing system. It has visuospatial complex

featuresthatincreases neurocognitive load on the brain cortical areas, explored using fMRI.No

literature is available reporting cortical sources of visuospatial complexity of Hindi language

using QEEG in a healthy control. This becomes imperative as this visuospatial complexity is

known to be affected in dyslexic children in Hindi language.

Objectives: To study the cortical sources activated during presentation of visuospatially

complexwords versus visuospatially simple words with meaning in Hindi language using

QEEG.

Methods: Twenty healthy volunteers (23.7 ± 3.1 yrs.) were presented with 30 complex

words(with vowels diacritics and ligature consonants) and 30 simple Hindi words in a

visuospatial complex task. Continuous 128 channel EEG data was recorded, preprocessed

and segmented into 1 second epoch from stimulus onset. Source localization was performed

using sLORETA. The activity of neural sources involved in processing of complex and

simple Hindi words were compared statistically using non-parametric mapping.

Results: The estimation of sLORETA inverse solution showed significant (p = 0.05; t

=1.169) left lateralized activation of middle and inferior frontal gyrus (BA 11,47) and

superior temporal gyrus (BA 38) during the presentation of complex word compared to

simple words.

Conclusion:The cortical activation pattern was specific to the complexity of the word leading

to activation of middle and inferior frontal gyrus and superior temporal gyrus. Left middle

frontal gyrus is involved in spatial and verbal working memory. Left inferior frontal gyrus

and superior temporal gyrus are associated with retrieval of the sound from spelling

(Grapheme-phoneme correspondence) while processing complex orthographic features of the

Hindi language. Thus, complex word processing relies more on grapheme phoneme mapping

and is driven more phonologically. These words also recruit spatial and working memory

areas while processing complex orthography.

Keywords: Visuospatial complex task, Visuospatial complex and simple words, QEEG,

sLORETA, Statistical non-parametric mapping

Total word count of the abstract: 317

MSc-24

Title: Effect of rTMS therapy on pain status, thermal sensitivity in Myofacial Pain

Dysfunction syndrome

Author List: Sharma G1, Arya S1, Gupta S2, Bhatia R1

Affiliation:1Department of physiology, 2Department of OMDR

All India Institute of Medical Sciences, New Delhi, India

Presenting Author:

Dr Garima Sharma

Department of Physiology, AIIMS, New Delhi

Email id: garimasharma9191@gmail.com

Corresponding Author:

Dr RenuBhatia

Department of Physiology, AIIMS, New Delhi

Email id:renuaiims28@gmail.com

Number of words: 350

Abstract body

Introduction:

Myofacial pain dysfunction syndrome (MPDS) is a chronic pain disorder, in which unilateral

pain is referred from the trigger points in myofacial structures, to the muscles of the head

and neck.The most accepted treatment regimen include low level laser therapy along with

conservative therapy but the use of photobiomodulation cannot be recommended as a

predictable and reliable treatment modality for MPD.Recently non-invasive techniques such

as brain stimulation have emerged which have potential to relieve pain and associated

spasm in chronic muscular pain disorders. In MPDS desensitization occur at the level of the

brainstem. Since pain and muscle spasm co-exist in MPDS so we hypothesise it may play a

beneficial role in its management.

Aim and objectives:

To study the effect of repetitive Transcranial Magnetic Stimulation on pain status, thermal

sensitivity of masticatory muscles in Myofacial Pain Dysfunction Syndrome.

Materials and methods: Randomised control trial (interventional). 20 diagnosed cases of MPDS were recruited based on laskin’s criteria and were randomly divided into real and sham group. Patients contraindicated to TMS were excluded from study.Repetitive TMS was given to the patients using NeuroMS/D Neurosoft stimulator using a figure of eight coil on motor cortex for 7

consecutive daysat 10 Hz frequency at 90% RMT with each session containing 1200 pulses in 20 trains at 60 second inter-train. To evaluate the pain status questionnaires like Visual Analog Scale (VAS), Maximum mouth opening (MMO) and Mc Gill Pain Questionnaire- short form (MPQ-SF) were included. For thermal sensitivity testing (CPT, HPT) first at left hand (first web space) was done and then the tests were repeated at unaffected and affected Masseter.

Results:

Significant decrease in pain rating score (VAS), MPQ-SF score (p< 0.000001), HPT and CPT of

affected site (P=0.0005)after rTMS therapy in real group when compared to sham

group.Significant increase in mouth opening (p=0.0028) after rTMS therapy was seen in real

group.

Conclusion:

We conclude that high frequency rTMSof motor cortex is effective in ameliorating MPDS

pain and correcting sensory deficit. Hence it may be considered as a therapeutic

intervention in Myofacial pain dysfunction syndrome.

-------------------------- (End of abstract)----------------------------