The Neurocognitive Effects of Total and Partial Sleep Deprivation in Younger Adults.

The Effect of Total and Partial Sleep Deprivation on Brain Function and Cognitive Functioning In Healthy, Younger Adults.

This study aims to examine how total and partial sleep deprivation affect brain function, cognitive performance, and biomarkers related to stress and inflammation in the same participants using a crossover design. The study will also compare the effects of total and partial sleep deprivation to determine whether these conditions affect the brain and body differently. The findings may improve our understanding of the consequences of sleep deprivation and help inform strategies to reduce its negative impact on health and society.

• How does total versus partial sleep deprivation affect brain activity during rest and cognitive tasks?
• How does sleep deprivation affect functional connectivity between brain networks?
• How does sleep deprivation affect working memory, attention, and executive control?
• How does sleep deprivation affect biomarkers of stress and inflammation, such as cortisol?
• Are changes in brain activity and connectivity associated with changes in cognitive performance and biological markers?
• Can combining MRI-based and non-MRI-based measures provide a more complete picture of the effects of sleep deprivation?

Participants will complete three study conditions in a randomized order:

Total Sleep Deprivation (TSD): 28 to 32 hours of continuous wakefulness. Partial Sleep Deprivation (PSD): sleep restricted to 4 hours per night for two consecutive nights.

Normal Sleep (control condition): a night of habitual sleep without sleep restriction.

Study Overview

• Status: Not yet recruiting
• Conditions: Sleep Deprivation
• Intervention / Treatment: Behavioral: Normal sleep; Behavioral: Total sleep deprivation; Behavioral: Partial sleep deprivation

• Study Type: Interventional
• Enrollment (Estimated): 24
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Sweden
  • Örebro County
    • Örebro, Örebro County, Sweden, 70182
      • Örebro university
      • Contact: Pernilla Andersson; Phone Number: 019 30 30 00; Email: naps@oru.se

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Signed informed consent prior to any study-related procedures.
• Age 20 to 40 years.
• Normal weight at screening, defined as a BMI between 18.5 and 24.9.
• Willingness to comply with the study protocol.

Exclusion Criteria:

• Current diagnosis of a psychiatric or neurological disorder or syndrome.
• Current diagnosis of another medical condition that limits study participation.
• Diagnosed sleep disorder (e.g., insomnia).
• Self-reported poor sleep quality (>5 on the PSQI).
• Working permanent night shifts or rotating night shifts.
• Use of medications or dietary supplements considered likely to affect the study outcome measures (e.g., melatonin).
• Extremely high perceived stress (>26 on the PSS).
• Sleep apnea.
• Excessive alcohol consumption (>9 standard drinks per week or >3 standard drinks per occasion).
• Extreme morningness or eveningness (>69 or <31 on the MEQ).
• Excessive daytime sleepiness (>10 on the ESS).
• Lifestyle factors that may contribute to fragmented sleep (e.g., being a parent of young children).
• MRI contraindications: claustrophobia; shunts in the head; bullet fragments or metal fragments in the body; metal implants or electrodes in the body; left-handedness; previous head surgery; previous heart surgery; or ingestion of a video capsule that may remain in the gastrointestinal tract.
• Any other reason that, in the opinion of the investigator, makes participation inappropriate.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Normal sleep	Behavioral: Normal sleep; Normal (7-9 hours) sleep, following normal patterns of wakeup and sleep onset.
Other: Total Sleep Deprivation	Behavioral: Total sleep deprivation; No sleep for 28-32 hours.
Other: Partial Sleep Deprivation	Behavioral: Partial sleep deprivation; Restriction to 4 hours sleep/night for two consecutive nights.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Brain functional activity and connectivity (PVT)	Compare normal sleep to SD (total and partial)	3 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Brain functional activity and connectivity (PVT) - SD	Compare total sleep deprivation and partial sleep deprivation.	3 weeks
Brain functional activity and connectivity (NBACK)		3 weeks
Brain functional activity and connectivity (MST)		3 weeks
Brain functional activity and connectivity (SST)		3 weeks
Brain functional activity and connectivity (EMOREG)		3 weeks
Resting state fMRI	Total SD vs Partial SD	3 weeks
Structural MRI	Total SD vs. Partial SD	3 weeks
Diffusion tensor imaging	Total SD vs Partial SD	3 weeks
Cognitive function (NBACK)		3 weeks
Cognitive function (MST)		3 weeks
Cognitive function (SST)		3 weeks
Cognitive function (EMOREG)		3 weeks
Levels of inflammatory markers (e.g. high sensitivity C-reactive protein (hsCRP), interleukin (IL)-6, tumor necrosis factor (TNF)-alpha)		3 weeks
Levels of neural function markers (e.g. brain derived neurotrophic factor (BDNF)		3 weeks
Salivary biomarkers (e.g., melatonin and cortisol)		3 weeks
Electrophysiological measures (e.g., ECG)		3 weeks
Assessment of psychological health using Hospital Anxiety and Depression Scale (HADS)		3 weeks
Assessment of psychological health using Pittsburgh Sleep Quality Index (PSQI)		3 weeks
Assessment of psychological health using Perceived Stress Scale (PSS)		3 weeks
Assessment of subjective sleepiness using the Karolinska Sleepiness Scale (KSS)		3 weeks
Assessment of sleep quality and sleep disturbances using the Karolinska Sleep Questionnaire (KSQ)		3 weeks
Assessment of daytime sleepiness using the Epworth Sleepiness Scale (ESS)		3 weeks
Assessment of chronotype (morningness-eveningness preference) using the Reduced Morningness-Eveningness Questionnaire (rMEQ)		1
Assessment of sleep-related positive and negative affect using the Negative and Positive Affect Scale for Sleep (NAP-AS)		3 weeks

Other Outcome Measures

Outcome Measure	Time Frame
Faecal samples for evaluation of gut microbiota composition	1 day
Levels of neural function markers (e.g. S100B)	3 weeks
Physical activity assessed using actigraphy	3 weeks

Collaborators and Investigators

• Sponsor: Örebro University, Sweden

Study record dates

Study Major Dates

• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): June 1, 2027
• Study Completion (Estimated): June 1, 2027

Study Registration Dates

• First Submitted: September 9, 2026
• First Submitted That Met QC Criteria: September 9, 2026
• First Posted (Actual): September 16, 2026

Study Record Updates

• Last Update Posted (Actual): September 16, 2026
• Last Update Submitted That Met QC Criteria: September 9, 2026
• Last Verified: September 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Mental Disorders; Sleep Wake Disorders; Dyssomnias; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Sleep Deprivation
• Other Study ID Numbers: Dnr: 2026-03064-01; 20230004-H-01 (Other Grant/Funding Number: The Knowledge Foundation)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No