Dr. Nguyen Huu Khanh, Department of Neurology, Neuroscience Center, Tam Anh General Hospital, TP HCM, states that adults should sleep about 7-9 hours per night. When sleep duration consistently exceeds 9-10 hours a day, accompanied by fatigue, reduced concentration, headaches, or mood changes, it may not simply be "catching up on sleep" but rather a sign of a brain abnormality.

Sleep is regulated by circadian rhythms and neurotransmitters such as serotonin, dopamine, and melatonin. Oversleeping disrupts the natural wake-sleep cycle, making it difficult for the brain to maintain a stable state of alertness during the day. The central nervous system becomes sluggish, slowing down information processing speed and reducing the ability to focus.

Excessive sleep affects the hippocampus, a crucial structure related to memory, promoting cognitive decline. Individuals who sleep a lot but still feel tired may suffer from sleep disorders like sleep apnea, which prevents the brain from receiving enough oxygen during the night.

In some cases, abnormal oversleeping is a symptom of depression, anxiety disorders, or emotional dysregulation. When serotonin and dopamine levels are imbalanced, patients tend to experience prolonged sleepiness, reduced interest, and low energy. Conversely, physical damage in the brain, such as brain tumors, encephalitis, endocrine disorders, or sequelae after traumatic brain injury, can also alter the sleep-regulating center.

Individuals who sleep more than 9 hours daily have a higher risk of headaches. This is because oversleeping disrupts circadian rhythms and fluctuates neurotransmitters, triggering headache episodes.

According to Dr. Khanh, if sleeping over 10 hours daily persists for many weeks, accompanied by memory loss, persistent headaches, dizziness, or behavioral changes, patients should seek a neurological examination to rule out pathological causes. A doctor may order a brain CT scan to detect structural damage like hemorrhage or space-occupying lesions; a brain MRI helps evaluate brain parenchyma in detail, enabling early detection of brain tumors, encephalitis, or damage to the sleep-regulating region.

Patients with sleep disorders can be treated with transcranial magnetic stimulation. Photo: Tam Anh General Hospital

For patients whose excessive sleep is related to depressive disorders or mood dysregulation, transcranial magnetic stimulation (TMS) may be used. This technique uses magnetic fields to selectively stimulate cortical regions involved in emotion and sleep, helping to regulate neural activity non-invasively and limiting systemic side effects.

Dr. Khanh advises that to protect brain health, everyone should maintain a regular sleep schedule, going to bed and waking up at the same time each day. Limit excessive "catch-up" sleep on weekends, increase physical activity, and avoid using electronic devices before bed.

Trong Nghia