Sleep Quality and Cognitive Functions in Adults: A Cross-Sectional Study

NCT07387783 | Recruiting

• 2 other identifiers: 61351342/020-1143TUBITAK 2209A 1919B012466805
• Study Type: observational
• Target: 75
• Locations: 1 country
• Sites: 1

Brief Summary

This observational cross-sectional study aims to examine the association between sleep quality and cognitive functions in healthy young adults. Subjective sleep quality will be assessed using the Pittsburgh Sleep Quality Index, and objective sleep parameters will be collected using a wearable device over five consecutive days. Cognitive functions will be evaluated at a single assessment session using standardized neuropsychological tests, including measures of attention, executive functions, and verbal memory. The study seeks to explore relationships between subjective and objective sleep measures and cognitive performance. Findings from this study may contribute to a better understanding of how sleep quality is associated with cognitive functioning in healthy young adults.

Conditions

Cognitive Functions; Sleep Quality

Keywords

sleep quality; Cognitive Function; Young Adults; verbal memory; wearable device

Outcome Measures

Primary Outcomes (1)

• Composite Objective Sleep Quality Index Derived From Wearable Device

  A composite objective sleep quality index will be derived from wearable device data collected continuously over five consecutive days. The composite score will be calculated by combining standardized values of total sleep time, sleep efficiency, sleep onset latency, and wake after sleep onset into a single summary measure representing overall objective sleep quality.

  During 5 consecutive days around baseline assessment

Secondary Outcomes (3)

• Sleep Quality (Pittsburgh Sleep Quality Index Scores)

  Baseline (single assessment)

• Cognitive Performance (Victoria Stroop Test Scores)

  Baseline (single assessment)

• Verbal Memory Performance (Öktem Verbal Memory Processes Test Scores)

  Baseline (single assessment)

Study Arms (1)

Healthy Young Adults

Healthy young adult participants without diagnosed neurological, psychiatric, or sleep disorders who undergo assessment of sleep quality and cognitive functions during a single observational assessment period.

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

The study population consists of healthy young adults aged between 18 and 35 years. Participants are recruited from a non-clinical population and are required to be fluent in Turkish to ensure valid administration of cognitive assessments. Individuals with self-reported good general health and without active medical, neurological, or psychiatric conditions that may affect sleep or cognitive functioning are eligible. All participants are able and willing to comply with the study procedures, including wearing a wearable sleep monitoring device for five consecutive days and completing a single-session cognitive assessment.

You may qualify if:

• Between 18 and 35 years.
• Ability and willingness to provide written informed consent.
• Sufficient ability to read, understand, and communicate in Turkish, the language in which the assessments are administered.
• Self-reported good general health, with no active medical or psychiatric conditions that significantly affect daily functioning.
• Willingness and ability to wear a wearable sleep monitoring device continuously for five consecutive days and to comply with device usage instructions.
• Ability to attend and complete a single-session cognitive assessment

You may not qualify if:

• Regular or frequent use of medications known to affect sleep or cognitive function, including sedative-hypnotics, benzodiazepines, antipsychotics, stimulants, opioids, or similar agents.
• Initiation of, or dose changes in, psychotropic medications within the past four weeks.
• Being under the influence of alcohol or illicit substances on the day of cognitive testing.
• Engagement in night shift work or rotating shift schedules within the past one month.
• Travel across time zones resulting in a time difference of two hours or more within the past two weeks.
• Uncontrolled high daily intake of caffeine (e.g., \>400 mg/day) and unwillingness to reduce consumption during the study period.
• Color blindness or other color vision deficiencies, due to their potential impact on Stroop Test performance.
• Dermatological conditions, allergies, or skin lesions at the wrist that prevent wearing the device, or refusal to wear the device as required.
• Acute illness within the past two weeks, including febrile infections, severe pain, or other acute medical conditions that may temporarily affect sleep or cognitive performance.
• Pregnancy or early postpartum period.

Sponsors & Collaborators

• Uskudar University: lead
• The Scientific and Technological Research Council of Turkey: collaborator

Study Sites (1)

Üsküdar University

Istanbul, Turkey (Türkiye)

RECRUITING

MeSH Terms

Conditions

Sleep Initiation and Maintenance Disorders

Condition Hierarchy (Ancestors)

Sleep Disorders, Intrinsic; Dyssomnias; Sleep Wake Disorders; Nervous System Diseases; Mental Disorders

Study Officials

• Fatma Demir, MSc

  Üsküdar University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Fatma Demir

CONTACT

(0216) 400 22 22; fatma.demir@uskudar.edu.tr

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: January 21, 2026
• First Posted: February 4, 2026
• Study Start: January 26, 2026
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): August 1, 2026
• Last Updated: April 29, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)