Have you ever woken up in the morning (or afternoon) in a cloud of worry after having a few drinks the night before?
As this holiday season draws to a close, after weeks of Christmas festivities, holidays and New Year’s celebrations, many of you may experience hangover anxiety or “anxiety” after getting too happy. .
As a neuroscientist researching how food and drink affect brain function, let me explain how drinking alcohol can cause anxiety the next day.
From tequila to endorphins and dopamine
Alcoholic beverages (beer, wine, or spirits) alter the delicate balance of chemicals in the brain, called neurotransmitters. Alcohol exerts a cocktail of effects on brain function that may be enjoyable at the time, but much less fun the next day.
The pleasurable effects of alcohol are due to the release of endorphins, natural opioid hormones in the brain.
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The good feelings also come from alcohol which increases dopamine release by activating the brain’s reward system, the mesolimbic pathway. Dopamine release reinforces behaviors, making it more likely that we will do what has caused a new dopamine surge.
So we quickly learned that the shot of tequila or glass of wine made us feel good and made us want more.
But alcohol affects more than the brain’s rewarding chemicals. Alcohol modifies the levels of neurotransmitters that control brain activity and function. Brain imaging shows that alcohol decreases activity in the prefrontal cortex and temporal lobe: key centers for decision making, self-control, and memory.
Feelings of anxiety, discomfort and stress
Alcohol increases the activity of the brain’s main chemical inhibitor GABA (gamma-aminobutyric acid) by mimicking its effects on synapses, connections between neurons.
GABA reduces the activity of a neuron and alcohol exaggerates this effect. The increase in GABA promotes feelings of relaxation and calm, which makes us more sociable and less stressed.
After several drinks, alcohol blocks the glutamate system. Glutamate is the main excitatory transmitter in the brain and plays an important role in the formation of memories and emotions.
The balance between GABA and glutamate is vital for optimal brain function. Alcohol changes this balance. Alcohol is called a central nervous system depressant because it increases inhibitory GABA and decreases excitatory glutamate.
When the brain detects high levels of GABA and low levels of glutamate, it adapts quickly to counteract this imbalance. The compensatory changes produce low levels of GABA and increased glutamate causing feelings of anxiety, discomfort, and stress, which will last until the next day.
Oh no … did I really do that?
After several alcoholic beverages, glutamate transmission decreases in the medial temporal lobe, the brain region where memories are formed.
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Alcohol-induced amnesia, or “shutdowns,” is caused by a rapid rise in blood alcohol levels, often due to excessive alcohol consumption. An excess is defined as more than four or five drinks in two hours for women and men, respectively.
In the sober brain, memories are formed after information is transferred from short-term memory to long-term memory. This process is called memory consolidation. Memories of events can be retrieved and remembered.
Alcohol interferes with the consolidation and retrieval of memories, causing confusion and uncertainty the next day. These nebulous memories of the events of the night (“Oh no … did I really do that ?!”) can cause great anxiety.
Alcohol also drastically alters sleep quality, reducing sleep in the REM phase when dreams occur. REM sleep is key to encoding long-term memories. Therefore, a bad night’s sleep after drinking alcohol can cause memories to fragment.
Shy people suffer more
Not everyone experiences anxiety, but some may experience it more than others. A recent study found that the intensity of an anxiety experience varies between people depending on personality traits, while controlling alcohol consumption and blood alcohol levels.
People with more reported shyness traits experienced increased levels of anxiety after drinking alcohol than people who had lower baseline levels of shyness.
Can anxiety be avoided?
The only guaranteed way to avoid hangover anxiety is not to drink alcohol.
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However, you can reduce the adverse effects of alcohol by drinking less. By separating drinks with glasses of water, you can prevent the rapid rise in blood alcohol that harms memory and stay hydrated to lessen the headache the next day.
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