So often we at The Glenner Memory Care Centers blog focus on how memories are impaired through disease and disorders. So today we thought we'd feature a piece in the Johns Hopkins Health Alerts e-newsletter on how we normally create memories. The following is from that article on memory and emphasizes three stages in a complex process.
Memory Acquisition: Learning new information activates neurons (nerve cells) in the brain. Communication among these nerve cells encodes the information, creating a temporary neuronal pathway that holds the information as a short-term memory. If you perceive something visual or spatial, such as a picture, the pathway is created in the right parietal lobe; if you're reading, the pathway forms in the area of the brain that processes language, the left temporal lobe. Focusing attention on new information promotes the encoding process, which then helps it solidify from short- to long-term memory during consolidation. That means that if you have a problem remembering something, maybe you weren't concentrating on it too hard in the first place.
Memory Consolidation: For information to be retained long term, the neural pathway formed during memory acquisition must be strengthened. The replaying of events in the brain strengthens the pattern of neuronal activity, as more elaborate connections (or synapses) are formed among the neurons.
Memory Retrieval: In order to recall something, the brain must reactivate the nerve pathways where the specific memory is stored. Frequently retrieved memories are usually easier to recall, whereas infrequently retrieved information often takes longer to emerge and may require a prompt of some kind, such as a related piece of information.
What happens as we age. With the onset of middle age, many people become more distractible and less able to fully concentrate on new information. This deficit weakens the memory acquisition process. The brain also becomes less efficient in consolidating new memories. Some researchers suspect that it may also take longer to "reassemble" a memory during the retrieval process.