Hypersomnia, commonly known as excessive sleepiness, is a sleep disorder that affects a significant number of individuals, impacting their quality of life. This condition is characterized by prolonged nocturnal sleep or excessive daytime sleepiness. Individuals afflicted with hypersomnia may sleep for long durations at night and still feel compelled to nap excessively during the day. In severe conditions, such individuals may even sleep for more than 10 hours but wake up feeling unrested.

Hypersomnia is commonly classified into primary and secondary types. Primary hypersomnia is typically idiopathic, which means it occurs without any identifiable medical or psychiatric cause. It is believed to result from a neurological disorder. Conversely, Secondary hypersomnia is the result of conditions like sleep apnea, Parkinson's disease, kidney failure, or chronic fatigue syndrome, which foster excessive sleepiness.

The symptoms can include anxiety, increased irritation, decreased energy, restlessness, slow thinking, slow speech, loss of appetite, and memory difficulties. Chronically afflicted individuals may also suffer social, professional and academic problems due to their inability to stay awake and focused. Day to day activities can become herculean tasks needing monumental effort because of the constant lethargy and the overwhelming desire to sleep.

The exact cause of hypersomnia remains unknown. However, researchers have identified certain potential triggers, including genetics. Studies suggest that individuals with a family history of the disorder are more likely to develop it. In addition, hypersomnia can occur after head trauma or injury to the central nervous system. Other potential triggers can be linked to other sleep disorders, psychiatric disorders, and substance misuse.

Diagnosing hypersomnia requires a comprehensive medical evaluation, because its symptoms can mimic other conditions. It often involves undergoing sleep studies such as polysomnography (overnight sleep test) and multiple sleep latency tests which measure the speed of falling asleep and the sleep cycle stages. Furthermore, medical practitioners can use the Epworth Sleepiness Scale; a self-report questionnaire that asks about the probability of falling asleep in common situations.

Currently, there's no cure for hypersomnia, but the condition can be managed. Treatment usually involves stimulant medications like Modafinil that promote wakefulness. Also, changes in lifestyle, including improvements in sleep hygiene and a healthy diet, can significantly benefit those living with the disorder.

In conclusion, hypersomnia is a serious physiological condition requiring medical attention and isn't simply an individual choosing to sleep excessively. Even though hypersomnia cannot be completely 'cured,' it can be effectively managed, enabling individuals to lead a normal life. Greater public awareness about this disorder is paramount in helping those affected to recognize their symptoms and seek appropriate aid.