Stress and Short Term Memory

acupuncture

The prefrontal cortex is the part of our brain that deals with so called ‘executive function’. It is responsible for our working memory, or short term memory. For example someone gives you a 10 digit phone number and how long you can recall that number is a reflection of how your prefrontal cortex is working in that moment.  The prefrontal cortex is a decision maker and planner. It helps us express ourselves and navigate social settings. A damaged prefrontal cortex impairs short term memory recall and is often a cause of personality changes such as irritability or anger.

Prefrontal cortex damage may conjure images of physical head trauma such as concussions.   NFL players for example. Or perhaps the incredible story of Phineas Gage where a projectile passes in, through and out of the head. However the damage doesn’t need to be physical trauma.  It can simply be everyday psychological/emotional trauma.  Or even a lack of sleep.
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A study just released in the Journal of Neuroscience was one of the first look at elevated cortisol levels and damage to the prefrontal cortex. Cortisol is a hormone that we need to keep functioning – without an appropriate amount of cortisol we’d be an exhausted vegetable.  Cortisol is produced in response to a ‘fight or flight response’.  We need some, however too much can cause cellular damage the same way repeated corticosteroids such as Prednisone cause cellular damage.(Cortisol is the most anti-inflammatory endogenously made hormone in the body).

In this study the researchers looked at what are called the synapses which are the connections that are necessary for processing, storing and recalling information.   They showed that as we age and have repeated experience of high cortisol levels the synapses shrink or disappear. Have you experienced not being able to remember some simple set of numbers or tasks while you were stressed, or perhaps you did not get enough sleep the prior night. (which can increase cortisol levels).   Have you not been able to recall something from yesterday or earlier in the day, but can recall details from 10 years ago? Old memories are stored differently and are less effected by the stress response whereas our working memory is directly impacted by stress.

Besides cellular damage from cortisol when we are stressed blood is diverted from the brain to the extremities.   Less blood means less oxygen to the brain.  The cortisol may also damage the brain by flooding calcium into the brain.  There are several mechanisms where excessive stress can contribute synapse damage. How do we measure cortisol?   You can get a blood test however a more accurate representation of how your hormonal levels are fluctuating is a 4x cortisol salivary test.   There are several labs that do this and in my office I use Diagnostech’s Adrenal Stress Index (ASI) Panel.  You spit into a tube at morning arising, lunch, dinner and before bed.   Four cortisol readings along with other related hormones are charted out to identify hormonal dysregulations occurring. The cost is $120, but many insurances now cover it.
If one feels stressed  or their ASI comes back showing a hyper adrenal state (too much cortisol) there are of course many lifestyle changes we can do to deal with stress and cortisol damage. Any kind of relaxation or meditation will drop cortisol levels.  Acupuncture most certainly is a great modality for stress as well as many herbal supplements such as the Ayurvedic herb ashwaganda.  Quite a bit of research has gone into the effect of phosphatidylserine (PS) and how it can decrease high cortisol levels, but it is a bit pricey.  It is a lot less expensive to meditate and breathe!   The well-known Relaxation Response is a great tool – there is a program at UMASS that I often recommend.

Breathe deep and relax to save your synapses.

Yours In Health

George Mandler

Licensed Acupuncturist

Licensed Dietiitan Nutritionist

References

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Courtney SM1, Petit L, Haxby JV, Ungerleider LG. The role of prefrontal cortex in working memory: examining the contents of consciousness. Philos Trans R Soc Lond B Biol Sci. 1998 Nov 29;353(1377):1819-28. PMID: 9854254. [PubMed] [Read by QxMD]

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Miller EK1, Freedman DJ, Wallis JD. The prefrontal cortex: categories, concepts and cognition. Philos Trans R Soc Lond B Biol Sci. 2002 Aug 29;357(1424):1123-36. PMID: 12217179. [PubMed] [Read by QxMD]

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Anderson RM1, Birnie AK1, Koblesky NK1, Romig-Martin SA1, Radley JJ2. Adrenocortical status predicts the degree of age-related deficits in prefrontal structural plasticity and working memory. J Neurosci. 2014 Jun 18;34(25):8387-97. PMID: 24948795. [PubMed] [Read by QxMD]

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Radley JJ1, Anderson RM, Hamilton BA, Alcock JA, Romig-Martin SA. Chronic stress-induced alterations of dendritic spine subtypes predict functional decrements in an hypothalamo-pituitary-adrenal-inhibitory prefrontal circuit. J Neurosci. 2013 Sep 4;33(36):14379-91. PMID: 24005291. [PubMed] [Read by QxMD]

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Schmidt LA1, Fox NA, Goldberg MC, Smith CC, Schulkin J. Effects of acute prednisone administration on memory, attention and emotion in healthy human adults. Psychoneuroendocrinology. 1999 May;24(4):461-83. PMID: 10341371. [PubMed] [Read by QxMD]

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Leproult R1, Copinschi G, Buxton O, Van Cauter E. Sleep loss results in an elevation of cortisol levels the next evening. Sleep. 1997 Oct;20(10):865-70. PMID: 9415946. [PubMed] [Read by QxMD]

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Dusek JA1, Benson H. Mind-body medicine: a model of the comparative clinical impact of the acute stress and relaxation responses. Minn Med. 2009 May;92(5):47-50. PMID: 19552264. [PubMed] [Read by QxMD]

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