Exploring memories and amnesia

Q. In soap operas, the writers love to include characters with amnesia who don’t remember their identities. Is it common for people to actually forget who they are?

It’s extremely rare. People with amnesia usually are aware of their identities. Amnesia, which means loss of memory, comes in several forms. The most common type is anterograde amnesia. People with this form have trouble learning and making new memories. Those who suffer from retrograde amnesia have an impaired ability to recall past events and information that was once familiar.

Transient global amnesia is a temporary loss of all memory, but you remember who you are, and you recognize people you know well. It is a rare form of the disorder.

Psychogenic amnesia is caused by trauma such as surviving an explosion. A victim of this form of amnesia can lose personal memories and autobiographical information briefly. This form of amnesia is probably the inspiration for all those soap scribes.

There are different types of memory affected by amnesia. Memory can be divided into:

• Immediate: Recalling information a few seconds after learning it

• Short-term: Recalling recently learned information minutes or more after presentation

• Long-term: Memory of remote events occurring months or years ago.

There are other memory definitions, too:

• Procedural memory about how to perform a task such as knitting

• Declarative memory about past information or experiences

• Semantic memory that is independent of time, such as vocabulary

• Episodic memory linked to a time such as a birthday

• Prospective memory about a future occurrence such as a planned meeting.

There are other symptoms of amnesia and may include confusion, disorientation, seizures, tremors, lack of coordination and false memories. Any trauma or disease that impacts the brain can affect memory. Some causes include brain tumors, heart attack, head injury, encephalitis (brain inflammation), stroke, carbon monoxide poisoning, dementia, seizures, electroconvulsive therapy, and drugs such as benzodiazepines that treat anxiety.

There are no drugs to treat most types of amnesia. Scientists are looking into brain neurotransmitters hoping to find ways to treat memory disorders.

For now, there are techniques being used to help people with amnesia. These include occupational therapy to develop memory and the use of electronic organizers, notebooks and photographs as reminders.