Short Term Memory and Long Term Memory

Short term memory and long term memory are divided into two main components:

1. Conscious memory (also called explicit or declarative memory), and

2. Unconscious memory (also called implicit or procedural memory)

Conscious memories relate to autobiographical details (“I graduated from college in 1980”), and learned information (“Paris is the capital of France”).

Unconscious memories encompass most motor skills (muscle memory), such as riding a bike or opening a door.

Short and Long Term Memory Overview


Short Term Memory

For the purpose of a discussion on memory loss, short term memory is equivalent to very recent memories, usually measured in minutes-to-days. Examples of short term memory include where you parked your car this morning, what you had for lunch yesterday, and remembering details from a book that you read a few days ago.

When people are concerned about “short term memory loss”, they are typically referring to real or perceived impairments in the ability to form new episodic and semantic memories.


Long Term Memory

For the purpose of a discussion on memory loss, long term memory is equivalent to more distant memories, usually measured in months-to-years-to-decades.

Examples of long term memory include recollection of an important day in the distant past (early birthday, graduation, wedding, etc), and work skills you learned in your first job out of school.

Long term memory is generally well preserved in early and mid-stage Alzheimer’s disease.

Brain regions responsible for healthy memory function include the temporal lobe and the hippocampus, a brain region under the temporal lobe: