If you cant remember what happened yesterday…blame your Hippocampus


As a teacher/lecturer for many years I always prided myself on knowing the names of every student in all my classes. I learned very early in my teaching career that knowing a student’s name was a very powerful motivator.

I remember someone telling me that the most important possession that a person owns in their name and to be recognised by your name is a sign of the respect and interest that you have in that person. What is it about people that make you remember them?. Is it their appearance, their clothing, their facial expressions, the way they talk etc.?

The part of the brain responsible for transferring this information into memory is a section called the Hippocampus, located on the inner most fold of the temporal lobe just under your temple. Names of people, machines, animals etc. are stored in this temporal lobe of the brain.

The Hippocampus is important for making new memories allowing us to live in the present and not in the past. Alzheimer’s disease affects the Hippocampus first causing early suffers to forget things that happen in the moment but can still remember things from the past.

The Hippocampus is also an important site in different types of mental illness such as depression, schizophrenia and Bi-Polar where it appears to start shrinking. Some reports indicate that this shrinking can be attenuated and even reversed with effective treatment.

Thirdly the hippocampus is directly affected by Estrogen. The Estrogen increases the density of the nerve synapses responsible for nervous activity and can delay the onset of memory loss. So you can see the Hippocampus is a very important part of the brain for retaining memories as well as living in the moment.

Sadly as we progress into old age the Hippocampus starts to shrink as a consequence of this ageing process and places us at an increased risk of dementia or memory loss. Even in older people who don’t suffer from dementia it will still shrink approximately 1-2 % per year eventually causing some memory loss.

With the percentage of people over 65 years increasingly living longer it is becoming imperative that some form of intervention strategy should be at the forefront of research. Physical activity has recently been recommended as a low cost treatment to stem the shrinking of the Hippocampus.

Considerable research is now emerging from animal studies that states increased physical activity can cause cell proliferation in the Hippocampus resulting in enhanced learning and memory retention.

Studies on older adults are now suggesting that moderate intensity physical activity can reverse the shrinking of the Hippocampus and assist with memory retention, which means that this problem is not inevitable but potentially controllable.

A one year study reported in the Proceedings of the National Academy of Sciences followed 120 sedentary older adults aged between 55″“80 years who were trained in a progressive exercise program of moderate intensity walking. After 12 months the physical activity group increased their Hippocampus volume by 2%, which offset its deterioration associated with ageing and effectively gave this group 1-2 years worth of volume to the Hippocampus!

Apparently the improvement is not universal as the anterior Hippocampus was the only section of the brain’s temporal lobe that showed improvement. This would indicate that physical activity does not influence all regions of the brain at the same rate.

Changes to the front of the Hippocampus resulted in an increase in a specific brain protein that is responsible for nerve cell growth also assisting with memory retention. The consistent physical activity over the 12 months also increased blood flow to brain supporting the notion that highly fit people present with greater volumes of the Hippocampus, which is critical for recording information for memory and adjusting to an environment and performing complex tasks.

Moderate intensity physical activity might specifically stem the decline in areas of the Hippocampus that tend to deteriorate the fastest in older adulthood. It is great news that moderate physical activity can increase the volume of your Hippocampus, increase your brain protein that is responsible for cell growth and increase your short term memory retention.

We could also say that those fitter older adults can potentially be protected against the loss of Hippocampus volume and retain memory for a longer period of time simply by being more physically active. Older adults need to remain active all their life. If they are not active or have never been active.. they need to start now! It’s a small investment for a huge dividend.

So if I meet you in the future and forget your name…blame it on my Hippocampus!

Dr Paul Batman
Director of Education
Australian College.