“Assessment of the association of Nidra (Sleep quality) with Smriti (Working memory) in healthy & shift workers – An analytical cross-sectional double-arm study’’

RESEARCH QUESTION:

What is the difference in Smriti (Working memory) of shift workers following different sleep

patterns to the normal shift workers (day shift workers) following normal sleep patterns?

NULL HYPOTHESIS (H0):

There is no difference in Smriti (Working memory) of shift workers following different sleep

patterns to the normal shift workers (day shift workers) following normal sleep patterns.

ALTERNATE HYPOTHESIS (H1):

There is difference in Smriti (Working memory) of shift workers following different sleep

patterns to the normal shift workers (day shift workers) following normal sleep patterns.

INTRODUCTION:

यदा तु मनसि क्लान्ते कमाात्मानः क्लमान्विताः |

सिषयेभ्यो सनितान्ते तदा स्वसिसत मानिः||1 ( च. िू. २१/३५)

Nidra is one of the three Upstambha of life. It is as important as that of Ahara and

Brahmcharya. It is said that when Mana gets exhausted due to excessive work and Indriyas

also gets rid of their work due to tiredness, then one sleeps.

अकालेऽसतप्रिङ्गाच्च न च सनद्रा सनषेसिता |

िुखायुषी िराकु याात् कालरासिररिािरा ||2 (च. िू. २१/३७)

Also it is said that Nidra taken out of time or in excessive amount or not taken properly is as

harmful as Kalratri and takes happiness away.

In Ayurveda text six types of Nidra are given in which ratriswabhava nidra is the nidra taken

at night and it is also consider as physiological .other five types are due to some pathology.3

रािौ जागरणं रूक्षं ……….. I4 (च. िू. २१/५०)

When this Ratriswabhav Nidra is hampered due to any reason and person wakes up throughout

night it causes vata dosh vruddhi. When vata dosha vruddhi occurs it affects Smriti.

स्मृसतबुन्विप्रमोहश्च………….II5 (च .िू .२१/४८)

Also Divaswpn (day sleep) causes Smritibuddhimohasch.

In Sushrut Samhita lakshan of Nidra taken in Samyaka kala are mentioned as

पुष्टि वर्ण बलोत्साहमष्टि दीप्तिमतंष्टिताम् ।

करोष्टत धातु साम्यं च ष्टििा काले ष्टिषेष्टवता ।।6 (िु. सच

. २४ /८८ )

Nidra taken at proper time causes nutrition of body, increment of complexion, strength and

joy. It increases agni, and causes proper balance of all the dhatus.

Smriti Vibhramsha is the state in which the memory is altered from its normalcy; this means

either reduced memory or selective memory or total loss of memory. In various classics,

scattered knowledge of Smritihrasa can be concluded as: Mana when hindered by Vata

pradhana Smriti Vibhramsha tridosha prakopa, leads to Rajo and Tamo Guna Vriddhi and

causing Avarana of Manovaha Srotasa (occlusion in channels of psychic activities) thereby

finally leading to Dhi, Dhriti and Smriti Vibhramsa7.

In modern science, Sleep quality is the measurement of how well you’re sleeping—in other

words, whether your sleep is restful and restorative. Four items are generally assessed to

measure sleep quality:8

Sleep latency: This is a measurement of how long it takes you to fall asleep. Drifting off

within 30 minutes or less after the time you go to bed suggests that the quality of your sleep

is good.

Sleep waking: This measures how often you wake up during the night. Frequent wakefulness

at night can disrupt your sleep cycle and reduce your sleep quality. Waking up once or not at

all suggests that your sleep quality is good.

Wakefulness: This measurement refers to how many minutes you spend awake during the

night after you first go to sleep. People with good sleep quality have 20 minutes or less of

wakefulness during the night.

Sleep efficiency: The amount of time you spend actually sleeping while in bed is known as

sleep efficiency. This measurement should ideally be 85 percent or more for optimal health

benefits.

Working memory9 is a cognitive system with a limited capacity that can hold information

temporarily. It is important for reasoning and the guidance of decision-making and behaviour.

Working memory is often used synonymously with short-term memory, but some

theorists consider the two forms of memory distinct, assuming that working memory allows

for the manipulation of stored information, whereas short-term memory only refers to the

short-term storage of information. Working memory is a theoretical concept central

to cognitive psychology, neuropsychology, and neuroscience.

NEED OF THE STUDY:

• In the description of Nidra, Ratriswabhav Nidra is naturally occurring as a

physiological process, others are due to some pathology

• As per Ayurveda Ratrijagaran causes Vata dosha vriddhi and Rukshta in the body.

Also, it is said that when Vata vriddhi occurs it affects the Smriti of the individual.

• “Currently more than 55 million people have dementia worldwide, over 60% of whom

live in low-and middle-income countries. Every year, there are nearly 10 million new

cases”.(WHO, March 2023)

• In Ayurveda Nidra and Smriti are considered to be closely associated but the evidence

for the same is less. This study is an approach to find out the association of Nidra and

Smriti, to fill the gap between concepts.

• It is needed to generate the evidence for evaluation of the association of Prakriti with

Nidra and Smriti which has been mentioned in classical Ayurvedic literature.

LITERATURE REVIEW:

CLASSICAL REVIEW:

1. In Charaka Samhita sutra sthan ekadashadyaya Acharya Charaka mentioned Nidra in

Trayaupstambh and it should be practice with caution. Also Nidra is one of the

Adharneeya Vega. Detailed description about Nidra is given in Charak sutra ekvinshati

adyaya asthauninditiya adhyaya.

2. In Sushrut Samhita, Nidra is mentioned as one of the five swabhavika roga.In Sushrut

Chikitsa 24 properties of kala nidra sevan are given.

3. Acharya Vagbhatt also refer Nidra as upstambh and adharneeya Vega.

In short all the acharyas mentioned nidra as an important factor for life and its contribution in health. Also Ratrijagaran and Divaswapa are prohibited.

Smriti Vibhramsha is the state in which the memory is altered from its normalcy; this

means either reduced memory or selective memory or total loss of memory. In various

classics, scattered knowledge of Smritihrasa can be concluded as: Mana when hindered

by Vata pradhana Smriti Vibhramsha tridosha prakopa, leads to Rajo and Tamo Guna

Vriddhi and causing Avarana of Manovaha Srotasa (occlusion in channels of psychic

activities) thereby finally leading to Dhi, Dhriti and Smriti Vibhramsa.

CONTEMPORARY REVIEW:

Sleep is a physiological process by which bodily functions are periodically rested. During

sleep, consciousness and power of will are partially or completely suspended and bodily

activity generally is greatly reduced. Sleep differs from alert wakefulness by loss of critical

reactivity to events in the external environment, therefore, subject can be aroused by sensory

stimulation.

Sleep requirement: 1. Newborn: 18 to 20 hrs

2. Growing children: 12 to 14 hrs

3. Adults: 7 to 9 hrs

4. Old persons: 5 to 7 hrs

Working memory (WM) is a cognitive construct that refers to the process of short-term

storage and management of information. Although it is often used as a synonym of shortterm

memory (STM), WM is frequently used to convey an additional emphasis on the

active manipulation of buffered information. In contrast, STM refers to information

storage without any type of manipulation and is, in fact, a key underlying process of

WM. It has often been connected or related to intelligence, information processing,

executive function, comprehension, problem-solving, and learning, in people ranging

from infancy to old age.

PREVIOUS WORK DONE:

S.NO.

TITLE              OF

ARTICLE

JOURNA

L

YEAR OF

PUBLICA

TION

AUTHOR

SUMMARY

|1.

Ratrijagarana night wakefulness and its impact on Manasika Bhava mental characteristics among industrial workers: A descriptive crosssectional study10

 JAIMS

2021

Elgeena

Varghese et al

A substantial change in Mana (non-distracted mind),

Chinta(anxiety/worry),

Dhairyam (courage), Harsha (joy), Veeryam (energy), Shraddha (desire), Medha

(intelligence),Avasthaana

(stability of mind), Vignyaana

(knowledge),                      Sanjna

(recognition), and      Smriti (memory).

|2.

RATRIJA

GARANA

(SLEEP

DEPRIVA

TION): A

MENACE

FOR

LIFESTY

LE

DISORDE

RS—A

REVIEW

11

IAMJ

2023

Thanusree        N

Nair

To prevent this sort of disease due to sleep deprivation, as per Acharya Charaka, those who are awakened during the night hours due to their work schedule the next day before the intake of food should sleep half of the awakened hours.

3.

Disturbance of the Circadian System in Shift Work and

Its Health

Impact12

     PMC

30      dec,

2021

Diane              B.

Boivin,PhilippeBoudreau, andAnastasi

Kosmadopoulos

Shift work leads to acute and chronic disturbances of sleep and alertness and an increased risk of fatigue-related incidents and accidents

|4.

Lack      of

Sleep May

Increase

Dementia

Risk13

NIH

14may

,2021

-

Analysis of the data showed that people in their 50s and 60s who got 6 hours of sleep or less were at increased risk of developing dementia later. Further research is needed to confirm this connection and understand the underlying reasons.

|5.

The effects of three consecutive 12-hour shifts on cognition, sleepiness, and domains of nursing performance in day and night shift nurses: A quasiexperimental

study14

  November

2021

Lois James , Nat haniel ElkinsBrown , Marian Wilson , Stephe n

M. James , Eliza beth Dotson , C harles

D. Edwards , La ura Winterstee n-

Arleth , Kevin St evens , Patricia Butterfield

 Nurses maintained their levels of performance for all domains after three consecutive shifts. Individual differences in predicted cognitive effectiveness could account for variation in performance by shift type for Communication skills but for no other domain of performance.

OBJECTIVES OF THE RESEARCH:

PRIMARY OBJECTIVE:

1. To assess the impact of Nidra (Sleep quality) on Smriti (Working memory) of

individuals working in different shifts.

SECONDARY OBJECTIVES:

1. To assess the association of Deha Prakriti with Nidra (Sleep quality) and Smriti

(working memory) of individuals working in different shifts.

MATERIALS AND METHODS:

Study Setting:- Delhi NCR

Study type:- Retrospective, Analytical cross sectional study

Population:- Shift workers (Day & Day-Night shift)

Grouping:- Two arm study

Group A: Day shift workers (working at the time for a minimum of 8 hours from atleast

past six months)

Group B: Day-Night shift workers (working at alternate day-night shift minimum 8 hours

for 15-30 days/month from atleast past six months)

Sample size – 100 in each group

SAMPLE SIZE CALCULATION:

Since we wish to know if work related shifts causes loss in memory scale, so we will

come to compare day shift workers and day-night shift workers for their memory status.

Here day shift workers means adults regularly working in day time & others means

day-night shift workers. Thus day-night shift workers may be treated as inference

group. Assuming that 20% point’s reduction may results due to shift workers sleep

patterns.

The calculated p value is 93 per group, assuming alpha 0.5, power 80% two sided test

assuming 10% dropout 102

Inclusion Criteria:

• Apparently healthy individuals of the age group 25-45 years irrespective of gender,

caste, and religion.

Participants should be Literate.

• Individuals, willing to participate.

• Group A: Day shift workers (working in day time for a minimum of 8 hours for at least

the past six months)

• Group B: Day-Night shift workers (working at alternate day-night shift minimum 8

hours for 15-30 days/month from at least the past six months

Exclusion Criteria:

Individuals having a history of any head injury, head surgery

• Individuals having a history of any major medical illness (HTN, DM, Parkinson’s

disease, Alzheimer’s disease, etc.)

• Individuals consuming any kind of medications, narcotics, etc. to induce sleep

• Individuals taking any medication to enhance memory.

• Individuals having drug and addiction (smoking) history.

• Pregnant and lactating mothers.

ASSESSMENT CRITERIA:

• Swasthya assessment scale (CSIR-IGIB/CCRAS) (Annexure 1)

• Prakriti pariksha using CCRAS Prakriti assessment Scale.

• Sleep quality assessment tool (Pittsburg Sleep quality Index).(Annexure2)

• PGI memory scale.(Annexure3)

• Lab investigation (for screening purpose) - CBC, Blood sugar, LFT, KFT, Thyroid

profile, Lipid profile.

• Melatonin hormone test (in selected participants, if feasible )

METHOD OF DATA COLLECTION:

• The data of the selected participants (those who comply with the inclusion criteria and

willing to take part in the study) will be collected.

• The selected participants shall undergo the series of events which include informed

consent about the study, their demographic details, a detailed history will be taken as

per the requirements of the study.

METHODOLOGY:

All involved procedures will be explained to the participants and written consent will be

taken.

A. Swasthya assessment & Lab investigations:

• Participant’s health will be assessed with the help of Swasthya assessment scale.

• Questions given in the scale will be asked and responses will be noted on the sheet.

• Assessment will be done on the basis of scoring & lab investigations. Apparently

healthy individuals will be screened and enrolled after fulfilling the inclusion criteria

for the next step of study.

B. Prakriti Parikshan

• Enrolled participants will be proceeded with assessment of Prakriti with the help of

CCRAS prakriti assessment scale.

C. Sleep quality assessment:

• Sleep quality will be checked with the help of PSQI

• Responses will be noted on the sheet

• Scoring will be done and participants will proceed for the next steps.

D. Memory assessment Test:

• Participants will be explained the SOP (Annexure 1) of the PGI memory assessment

scale before starting the test.

• Test will be done and responses will be noted.

• Interpretations will be done and conclusion will be noted.

END POINTS:

Primary end point – An association between Nidra and Smriti working memory will be

obtained.

Secondary end point –

1. Corelation between nidra and deha prakriti will be established.

2. Variation in working memory scale in relation with deha prakriti will be assessed

FLOW CHART OF OBSERVATIONAL STUDY

Individuals will be screened and participants will be

enrolled after taking written consent of the participants.

Swasthya assessment will be done using IGIB/CCRAS

swasthya assessment scale & lab investigation will be done.

Apparently healthy participants will get divided in group A and

group B as per the inclusion criteria.

Prakriti assessment will be done by using CCRAS

Prakriti assessment scale.

Sleep quality of the participants of both the groups will

be assessed by using PSQI

Memory assessment of both the groups will be done

using PGI memory scale

Data collected from every tool will be statistically

analyzed, discussion will be done, conclusion will be

drawn

STATISTICAL METHOD FOR ANALYSIS:

❑ The generated data will be presented in the form of Frequency distribution, Bar

diagrams wherever applicable and Chi-Square test will be used to compare between

groups.

❑ The data generated in the observational study will be analyzed to compare proportion

memory loss by using Z-TEST and other suitable tests will be used as per need.

❑ SPSS (Statistical Package for the Social Sciences) version 26 of programme will be

used.

❑ Data will be stored in password protected computer and at the end of the study all the

data will be handed over to the department.

ACCESS TO DATA AND CONFIDENTIALITY

Data confidentiality will be maintained and Primary data will be preserved in the concerned

Department for a period of 5 years.

ETHICS COMMITTEE CLEARANCE

• The study will be started only after getting clearance from Institutional Ethics Committee,

AIIA, New Delhi.

• The present study will be carried out after taking the written consent from the Study

Participants.

• The CTRI Registration will be done.

EXPECTED OUTCOME

• Decrease in working memory score will be obtained in disturbed sleep pattern

individuals.

FINANCIAL SUPPORT

PGI memory scale- 5,000

Melatonin kit- 40,000

Lab investigations- 180,000 (waived off by institute for research purpose)

Transport expenses- 30,000

Miscellaneous – 2,000

TOTAL- 257,000

This study will be completed within the prescribed financial limit for the work. However, if

more finance is required, the request will be made for due permission and approval of extra

budget to the concerned authority AIIA, in due course of research work