1.2.2 Psychological and sleep disturbances
The severity of hangover symptoms has also been associated with particular personality traits. For example, some research has indicated that individuals with personality traits that predispose them to a risk of alcoholism, experience more severe hangover symptoms than other people.
Although alcohol acts as a sedative, the sleep it induces can be of poorer quality and shorter duration than normal. Ethanol interferes with the action of key neurotransmitters, in particular GABA and glutamate, to cause an overall sedative effect. The body counterbalances this by changing the number of GABA and glutamate receptors present at the synapses, increasing the number of glutamate receptors and decreasing the number of GABA receptors. Ethanol is removed relatively quickly from the body, but it takes longer for the number of receptors to return to normal, leaving the nervous system in a temporary unbalanced, over-excited state.
What are the physiological signs associated with alcohol withdrawal?
Elevations in heart rate and body temperature, tremor, insomnia and anxiety.
Because the symptoms of hangover share many of the characteristics of alcohol withdrawal symptoms, a possible interpretation is that hangover may be a mild form of alcohol withdrawal.