NCT04984824

Brief Summary

To evaluate the nap duration that achieves maximal cognitive gain with practicality of implementation, the present work employs a within-subject design comparing nap durations of 10 minutes, 30 minutes, and 60 minutes with a no nap condition on benefits to alertness, vigilance, mood, speed of processing and memory over post-nap intervals of 5 minutes, 30 minutes, 60 minutes and 240 minutes. The effect of nap duration on memory encoding will also be examined.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
20

participants targeted

Target at below P25 for not_applicable

Timeline
Completed

Started Nov 2020

Shorter than P25 for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

November 1, 2020

Completed
4 months until next milestone

First Submitted

Initial submission to the registry

March 15, 2021

Completed
3 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

June 15, 2021

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

June 15, 2021

Completed
2 months until next milestone

First Posted

Study publicly available on registry

August 2, 2021

Completed
Last Updated

August 2, 2021

Status Verified

July 1, 2021

Enrollment Period

8 months

First QC Date

March 15, 2021

Last Update Submit

July 28, 2021

Conditions

Sleep

Outcome Measures

Primary Outcomes (5)

  • Picture encoding task

    Participants will observe pictures of non-famous people, landscapes, scenes and objects. Later they are tested on whether they remember seeing the picture previously or not. The encoding session will take 20-30 min, and the retrieval session will take 15 min.

    In total: 35-45 min

  • Levels of sleepiness

    Karolinska Sleepiness Scale. Participants rated their level of subjective sleepiness on a 9-point Likert scale (1 - very alert, 9 - very sleepy, great effort to keep awake).

    1 min

  • Mood

    Positive and Negative Affect Scale. On the Positive and Negative Affect Scale (PANAS), participants responded to 20 adjectives describing positive and negative mood states on a 5-point Likert scale (1 - very slightly, 5 - extremely). Positive and negative affect scores are represented by the sum of the item responses.

    1 min

  • Vigilance

    Psychomotor Vigilance Test. The 3-min PVT assessed levels of sustained attention. At intervals varying randomly from 2000 ms to 10000 ms, a counter on the screen appeared and participants were to press a key as quickly as possible. Lapses were defined as responses exceeding 500 ms.

    3 min

  • Speed of processing

    Digit Symbol Substitution Test. The 2-min DSST was used as a measure of speed of processing. In this task, participants were required to match symbols to digits as quickly as possible following a key shown on screen. The total number of correct trials was used as the critical measure.

    2 min

Study Arms (4)

No nap group

NO INTERVENTION

No nap opportunity will be given in this condition.

10 minute nap

EXPERIMENTAL

Participants will be given a 10 minute nap.

Behavioral: Nap duration

30 minute nap

EXPERIMENTAL

Participants will be given a 30 minute nap.

Behavioral: Nap duration

60 minute nap

EXPERIMENTAL

Participants will be given a 60 minute nap.

Behavioral: Nap duration

Interventions

Nap durationBEHAVIORAL

A cognitive battery which will be repeated at 1505, 1530, 1600 and 1900. Material for the picture encoding task will be learned at 1630 and will be tested at 2000.

10 minute nap30 minute nap60 minute nap

Eligibility Criteria

Age21 Years - 35 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • Participants aged from 21 - 35 years and who have an average sleep duration of 6-6.5 h are eligible for this study.

You may not qualify if:

  • Participants who have an average sleep duration of less than 6 h or more than 6.5 h, who report sleep apnea symptoms, who report drinking more than 5 cups of caffeinated drinks a day, who have a BMI greater or equal to 30, or report elevated depression or anxiety symptoms will be excluded.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Yong Loo Lin School of Medicine

Singapore, 117549, Singapore

Location

Related Publications (1)

  • Leong RLF, Lau T, Dicom AR, Teo TB, Ong JL, Chee MWL. Influence of mid-afternoon nap duration and sleep parameters on memory encoding, mood, processing speed, and vigilance. Sleep. 2023 Apr 12;46(4):zsad025. doi: 10.1093/sleep/zsad025.

    PMID: 36775965DERIVED

Study Officials

  • Michael Chee, MBBS

    National University of Singapore

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
TRIPLE
Who Masked
PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
Purpose
BASIC SCIENCE
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Professor

Study Record Dates

First Submitted

March 15, 2021

First Posted

August 2, 2021

Study Start

November 1, 2020

Primary Completion

June 15, 2021

Study Completion

June 15, 2021

Last Updated

August 2, 2021

Record last verified: 2021-07

Data Sharing

IPD Sharing
Will not share

Locations

SG(1)