How Biological Factors May Affect Memory By Mr Daniel Hansson

Question for Discussion Identify factors that affect the body and may indirectly have a negative effect on memory How much sleep per night do you think a teenager need on average? Calculate how much you sleep on average per night on a regular week What can you do to prevent memory impairment? What can you do to improve your memory?

Important Concepts Dementia: A gradual decline in cognitive function due to damage or disease in the body beyond what might be expected from normal aging Amnesia: Partial or total loss of memory What is the main difference between dementia and amnesia?

Biological factors That May Impair Memory Alzheimers´ disease Brain damage Sleep deprivation

Important Concepts: Alzheimers Disease Semantic memory: Memory for meaning, facts, words, knowledge Procedural memory: Memory for skills Neuroplasticity: The ability of the brain to change with learning. This ability is believed to decrease with age.

Alzheimers Disease A brain disease that starts with amnesia and gradually leads to dementia The brain activity is initially lowered in the back part of the brain (important for forming procedural memories), before it gradually moves forward

Alzheimers’ disease In the early stages, the most commonly recognized symptom is partial loss of the semantic memory In the middle stages, the individual has problems with her short term memory In the later stages, the individuals’ long term memory is severely impaired

Possible Cause of Alzheimers Possible Cause of Alzheimers?: Attack of the Cholesterol Metabolism on Neuroplastic Processes Cholesterol metabolism may lead to amyloidosis

Amyloidosis The amyloid protein is accumulated in the brain and impairs communication between brain cells

Destabilization of Brain Cells by the Tau Protein Once a critical point of amyloidosis is reached, invidual brain cells are destabilized by the Tau protein

Acetylcholine Acetylcholine, a chemical substance (neurotransmitter) in the brain that encourages learning may inhibit the attack on the brain’s neuroplastic processes

Other possible factors on Alzheimers disease Positive emotions Language ability Sleep deprivation Genetic factors Strokes

Important Concepts: Brain Damage Localization of function in the brain: The idea that different parts in the brain carry out different functions Hippocampus: Is found in the limbic system of the brain. Is important for long term memory, short term memory and spatial orientation Anterograde amnesia: Inability to form new memories Retrograde amnesia: Inability to remember past events

Amnesia through Brain Damage: What Type(s) of Amnesia? H.M.: Had two thirds of his hippocampus removed due to surgery. He lost 11 years of his past memories prior to the surgery. Was unable to form new memories

Amnesia through Brain Damage: What Type of Amnesia? Clive Wearing: Contracted a virus (Herpes simplex encephalitis) that attacked his brain. He has lost most of his past memories and is unable to form new memories.

Sleep Deprivation The average adult requires 8 hours of sleep per night. If she has less, she may suffer from sleep deprivation Sleep deprivation may lead to impaired learning, memory loss and an increased risk of developing Alzheimers disease (e.g. Kang et al. 2009; Holzman et al. 2009) It is possible to catch up on lost sleep (sleep debt), but if severe it can take months

Sleep and memory consolidation The younger you are, the more sleep you need. The average teenager requires 9.5 hours of sleep per night Procedural skills (e.g. talking, driving, playing music) are improved by sleep Studies on rats demonstrate that memory consolidation is most important within five hours of learning

Task Find and summarize one study that demonstrates the effect of biological factors on memory. Use the study summary worksheet and Summarize aim, research method, procedure, findings and conclusion Examples of biological factors include sleep, Alzheimers disease, insulin, hormones Brain damage or the H.M. case study is not allowed

Links to Suggested Studies http://www.sciencedaily.com/releases/2005/06/050629070337.htm http://www.sciencedaily.com/releases/2003/07/030709064042.htm http://www.nytimes.com/2001/05/07/health/07NUNS.html?pagewanted=all