Young adults are progressively affected by sleep deprivation due to excessive use of digital media, irregular lifestyles, social demands, and academic stress. Prolonged lack of sleep significantly impairs brain function, influencing mood, overall health, and cognitive function. Electroencephalography (EEG) is a non-invasive neurophysiological tool that plays a vital role in studying how sleep deprivation alters brain activity. EEG is a technique that records the electrical activity of brain by using electrodes placed on the scalp. This article explores EEG findings related to sleep restriction, focusing on changes in brain wave patterns, cognitive effects, and the overall impact of mental health in young adults.

EEG and how does it work?

Electroencephalography (EEG) is a neurophysiological technique that records the electrical activity of brain. It is a non-invasive technique that records the activity by using electrodes placed on the scalp. EEG plays a crucial role in understanding brain function, evaluating cognitive states and diagnosing neurological disorders. These electrical signals indicate the presence and patterns of brain waves, which vary in frequency and amplitude depending on level of alertness and their mental states.

Types of brain waves include:

EEG is mainly used for studying sleep because it monitors real-time changes in brain states and detects disruptions caused by sleep deprivation.

Sleep patterns and EEG:

Sleep patterns consist of Non-Rapid Eye Movement (NREM) and Rapid Eye Movement (REM) stages that cycle repeat throughout the night. NREM sleep is divided into three stages: N1, N2 and N3. There are changes in EEG patterns with each stage. EEG plays a crucial role in identifying each stage.

NREM1: transition stage from alpha to theta state and showing drowsiness

NREM2: it is marked by sleep spindles and k-complexes

NREM3:it shows high-amplitude delta waves.

REM sleep is marked by low-amplitude, mixed-frequency EEG patterns resembling wakefulness and is linked to intense dreaming and muscle paralysis.

In a normal adult, each sleep cycle lasts approximately 90 to 110 minutes and occurs 4 to 6 times during the night. In individuals lacking sleep, the normal sleep structure is disrupted. EEG reveals decreased slow-wave activity, interrupted sleep patterns, and changes in REM duration during recovery sleep.

EEG changes due to sleep deprivation:

Missing a full night’s sleep causes clear EEG changes:

• Increased Theta Waves– Seen in frontal/parietal areas, indicating fatigue and low alertness.
• Decreased Alpha Waves– Reflects reduced relaxed wakefulness.
• Slow-Wave Intrusions– Delta waves appear during wakefulness, causing brief “microsleeps.”
• Lower Beta/Gamma Activity– Affects higher cognitive functions like decision-making.

EEG and Cognitive Impairment in Sleep-Deprived Youth

EEG allows researchers to detect changes in brain activity that are connected to performance impairments. Key cognitive domains affected include:

• Attention Focus: A decrease in beta wave activity is linked to reduced alertness and a higher rate of reaction time errors.
• Working Memory: Reduced coordination of frontal theta waves disrupts the ability to retain and process information.
• Emotional Regulation: Changes in frontal EEG asymmetry, particularly after sleep deprivation, are connected to increased mood disturbances, such as irritability and anxiety.

Different EEG study based on real-life scenarios:

Recent EEG studies have looked at how sleep deprivation affects young adults in different situations:

• Academic Stress: College students show more theta activity and lower ERPs during exams, suggesting mental overload.
• Shift Work and Late Sleepers: Young people who work night shifts or stay up late have weaker alpha waves and slower brain recovery after losing sleep.
• Screen Time: Using digital devices before bed lowers alpha and delta brain waves during recovery sleep, which impacts brain rest and repair.

Recovery Sleep and EEG Changes

After short-term sleep loss, the brain tries to recover through "rebound sleep." EEG during this time shows:

• Higher Delta Waves: This shows the brain is trying to make up for missed deep sleep.
• Less REM Sleep: REM sleep is reduced for a short time but returns to normal after a few nights.

But with long-term sleep loss, this recovery doesn’t work as well, and EEG patterns stay disrupted for longer.

Implications for mental health and daily functioning

EEG research shows that long-term sleep deprivation in young adults raises the risk of:

• Depression and Anxiety: Caused by ongoing problems in frontal brain activity
• Burnout and Chronic Fatigue: Linked to high levels of theta waves
• Poor Academic and Work Outcomes: Due to lower cognitive alertness seen in EEG

These results highlight the importance of promoting good sleep habits and making policy changes, such as starting school later, to support better sleep in young people.

Conclusion

EEG helps reveal how the brain reacts to lack of sleep, showing clear changes in brain waves and thinking ability. These effects are more serious in young adults because of their stage of development, daily routines, and academic pressure. EEG findings stress the urgent need to address sleep loss to protect brain health, emotional well-being, and mental performance.

Written By:

Ms.Muskan

Assistant Professor

Department of Neurosciences

School of Allied Health Sciences

SGT University