• Business Insider spoke to Dr Sunjeev Kamboj, a clinical psychologist at University College London, about why we’re sometimes unable to recall details after a night of drinking. 
  • He said that the link between short-term and long-term memory is disrupted when alcohol is present in our blood
  • Dr Kamboj added that a “black-out”, where we’re totally unable to recall events, occurs when this link is completely severed, with people with a low alcohol tolerance at particular risk.

 

Full transcript below. 

Dr Sunjeev Kamboj: So, alcohol is actually quite a powerful amnestic drug, which means that it prevents the formation of new long-term memories, and this amnestic effect – this effect on memory – is graded, so it depends on how much you drink; the more you drink, the worse your memory becomes.

And it’s generally only memory for new things – learning new facts, learning about new events and so on.

Someone who has drunk a lot of alcohol can still recall very well events from the past, and they can even learn some new bits of information as long as they are only required to recall them over a short period of time.

The problem happens when we ask people to remember things for longer periods of time. Blackouts are a more pronounced form of amnesia, and they happen when – particularly in people who perhaps haven’t developed a strong tolerance to alcohol and drink a lot of alcohol in a short period of time, so binge drinking – and what seems to happen there is that the brain mechanisms that are involved in converting short-term memories into long-term memories is completely disrupted and there’s no possibility of forming a long-term memory when alcohol concentrations are so high.

Under those circumstances people can have very disturbing and frightening experiences because, in addition to having impaired judgement, they can’t remember at all what happened when they were drinking, and that leaves them to try to fill in the details of those events, and that could lead to all kinds of ideas about terrible things that might have happened.

Produced by Fraser Moore. Camera by David Ibekwe.