What is biological memory?

[cameron marical]

I was thinking about it, and I cant really remember ever learning this, and I can not seem to find anything on the internet, it is bugging me.

 

How do we remember something physically?

 

Surely nuerons cant connect for something like short term memory?

 

and, How does long term memory work?

 

Thanks.

[bascule]

Long-term memories manifest themselves as connections between neurons in the neocortex. Everything we've learned is stored in a maddeningly complex network of inter-neuron connections which take the form of axons and dendrites, the "arms" of neurons.

 

The general theory is that a brain structure known as the hippocampus accumulates short term memories, then programs them into the neocortex when we sleep. It's hypothesized that the act of dreaming is in some way related to the hippocampus programming our neocortex with long term memories.

 

The neocortex is arranged into a hierarchy, with all of our sense and motor functions down at the bottom, and the hippocampus on top. The lower levels of the neocortical hierarchy handle actions we perform often, such as walking down the street, handling the constantly changing terrain, and only consult higher levels when they encounter unexpected patterns. The more unexpected a particular pattern is, the higher it propagates up the neocortical hierarchy, until it needs a decision by the highest of highest levels. If the pattern is still unrecognized, it gets entered into the hippocampus, so all of the "new" stuff we encounter each day gets filed into the hippocampus, then the hippocampus "teaches" it to all the lower levels of the neocortex every time we enter REM sleep.

 

Drugs that interfere with the operation of the hippocampus, such as Rohypnol or benzodiazepines, bind to neuroreceptors in the hippocampus and interrupt its function, effectively wiping the memory you've accumulated throughout the day and rendering the entire experience as if it never happened. These drugs give you "blackouts" and it's as if the entire experience had never happened.

[Mr Skeptic]

Well, you have working memory which is extremely limited and in the form of electrochemical impulses, there's also short term and long term memory. The pattern of synapses (connections between nerve cells) plays a big role here. I've also heard that there may also be some information stored in the nerve cell's DNA via patterns of methylation (used to inactivate genes).

[bascule]

Well, you have working memory which is extremely limited and in the form of electrochemical impulses, there's also short term and long term memory. The pattern of synapses (connections between nerve cells) plays a big role here. I've also heard that there may also be some information stored in the nerve cell's DNA via patterns of methylation (used to inactivate genes).

 

Modern cognitive theory places the working memory in an incredibly complex and not very well understood structure: the thalamus, which has feedback loops running throughout the neocortex. Cortico-thalamo-cortical circuits allow the neocortex to feed back on sensory data, and perhaps "annotate" it with predictions/decisions about what it represents.

[cameron marical]

Thank you for the detailed reply, though I must say, I do not fully understand how we can actually remember things like images, etc... Is it in binary form similiar to a computer?

[bascule]

The exact workings of memory are not well known