Transient global amnesia (TGA)

Transient global amnesia (TGA) is a neurological disorder whose key defining characteristic is a temporary but almost total disruption of short-term memory with a range of problems accessing older memories. A person in a state of TGA exhibits no other signs of impaired cognitive functioning but recalls only the last few moments of consciousness, as well as possibly a few deeply encoded facts of the individual's past, such as their childhood, family, or home perhaps."

Source : Wikipedia

It's usually fairly short lasting; typically 2 - 8 hours. It's known that various triggers can lead to TGA episodes - such as: vigorous exercise - trauma - Migraineplugin-autotooltip__plain plugin-autotooltip_bigMigraine

"Chronic migraine has a great detrimental influence on a patient’s life, with a severe impact on socioeconomic functioning and quality of life. Chronic migraine affects 1–2% of the general population, and about 8% of patients with migraine; it usually develops from episodic migraine at an annual conversion rate of about 3%."
- intoxicants - Epilepsyplugin-autotooltip__plain plugin-autotooltip_bigEpilepsy

"Epilepsy is a chronic noncommunicable disease of the brain that affects around 50 million people worldwide. It is characterized by recurrent seizures, which are brief episodes of involuntary movement that may involve a part of the body (partial) or the entire body (generalized) and are sometimes accompanied by loss of consciousness and control of bowel or bladder function. Seizure episodes are a result of excessive electrical discharges in a group of brain cells. Different parts of …
&etc.

The underlying psycho-neural mechanisms which lead to an attack, and the way in which sufferers typically make a complete recovery in a few hours, are unknown.


Also see: Memoryplugin-autotooltip__plain plugin-autotooltip_bigMemory

inexplicable

"Although it is commonly accepted that learning and memory occur via enduring changes in neuronal properties such as synaptic strength within a network of neurons, many details of these processes remain unknown, including the mechanisms responsible for the persistence and maintenance of memory over long periods of time.
and Hangoverplugin-autotooltip__plain plugin-autotooltip_bigHangover

Despite its ubiquity and history spanning several thousand years, the understanding of alcohol-induced 'Hangover' is limited.

"Alcohol hangover is characterized by adverse physical and mental effects that occur the next morning after the intake of toxic doses of alcohol. This phenomenon is a very frequent experience among alcohol-consuming people and it has been associated to high socio-economic costs, mainly due to absenteeism and poor performance in academic and work settings. Mult…