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Advanced Neurology PSG findings in young poor sleepers

concurrent increase in N3 sleep (deep sleep) by 3.38% restriction, the sleep system prioritizes SWS during
(d = 0.70), though seemingly contradictory, may indicate available sleep windows. This aligns with previous studies
a compensatory homeostatic response to prior sleep showing SWS rebound following sleep deprivation.
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deprivation. Such an adaptation aims to prioritize Young adults, due to their developmental stage, naturally
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restorative slow-wave sleep (SWS) when sleep opportunity exhibit greater SWS propensity. This could account for the
is constrained. preserved or even enhanced N3 percentages despite overall
Notably, the reduction in N2 sleep to 51.10% from a poor sleep perception. Lifestyle factors such as physical
normative 53.70%, while modest, carries implications due exertion may further potentiate deep sleep generation.
to N2’s dominance in total sleep architecture and its role 4.2.3. REM sleep suppression and functional
in sleep spindles, memory consolidation, and transition implications
stability. 22,23 Elevated N1 and reduced REM, when
observed concurrently with lower N2, suggest destabilized REM sleep reduction, approximately 30% below normative
transitions between sleep stages, potentially arising from benchmarks, carries important functional ramifications.
stress-induced arousals. Even minor reductions in N2 Stress-related neurochemical imbalances, such as
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can significantly alter sleep continuity and subjective norepinephrine elevation, can suppress REM sleep, as can
perception, given its substantial share of TST. 15 behavioral sleep curtailment that shortens REM-rich final
cycles. Deficient REM compromises emotional resilience,
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The most pronounced change in architecture was the learning, and memory, increasing vulnerability to affective
nearly 30% reduction in REM sleep (from 19.7% to 14.0%, disorders. Participants may not explicitly report REM-
d = 1.89). This substantial loss implicates compromised related issues, but the resultant cognitive and mood deficits
emotional regulation, learning, and memory consolidation may manifest subtly in daily functioning. The absence of
processes. 25-27 Chronic REM sleep deprivation has REM-related complaints despite objective loss reflects the
been linked to increased stress sensitivity and mood broader theme of subjective-objective dissociation in sleep
disturbances, further exacerbating sleep-wake instability. 19 perception.
4.2. Neurobiological mechanisms and 4.3. Clinical implications and recommendations
interpretations
The study’s findings underline the importance of
4.2.1. Arousal system dysregulation combining subjective reports with objective sleep measures
Findings suggest dysregulation in arousal systems, when evaluating sleep quality in young adults. A notable
particularly involving the sympathetic nervous system and dissociation was observed between how participants
hypothalamic-pituitary-adrenal axis, both of which have perceived their sleep and what was revealed through PSG;
been implicated in the pathophysiology of insomnia. 21,28 for example, some participants reported poor sleep despite
Elevated N1, prolonged SOL, and extended ROL point to maintaining normal SE, highlighting the limitations of
sustained physiological arousal at sleep onset, disrupting self-report measures. This supports the use of tools such
the descent into deeper stages. This hyperarousal, as actigraphy or wearable sleep trackers in routine clinical
potentially triggered by stress or pre-sleep cognitive assessments, particularly when PSG is not feasible. These
activity, can impair sleep continuity even in the absence of devices can reveal hidden patterns such as reduced TST
external disruptions. 21,29 or prolonged latency, which may not be evident from self-

Furthermore, delayed REM onset may result from reports.
excessive noradrenergic and orexinergic activity, which Clinicians should also assess factors contributing to
inhibits the normal neurochemical cascade required for hyperarousal, such as stress, anxiety, or late-night screen
REM initiation. The perceptual distortions of sleep— use, which were indirectly suggested by the PSG data
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wherein participants report poor sleep despite objective (increased N1, reduced REM, and delayed sleep onset).
preservation of efficiency—are consistent with cortical Behavioral interventions like Cognitive Behavioral
hyperarousal and sleep misperception, as described in Therapy for Insomnia (CBT-I), even when insomnia
paradoxical insomnia. 30-33 criteria are not fully met, could be adapted for young
adults. Techniques including sleep hygiene education,
4.2.2. Homeostatic sleep drive and deep sleep stimulus control, and relaxation strategies may reduce
compensation cognitive arousal and improve sleep quality. Emphasizing
The elevated N3 sleep observed suggests an intensified regular sleep schedules, reducing evening light exposure,
homeostatic response, as postulated in the two-process limiting caffeine intake, and fostering calming bedtime
model of sleep regulation. Under chronic partial sleep routines can further support this population.
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Volume 4 Issue 4 (2025) 73 doi: 10.36922/an.8614