Jamie Hale

Jamie Hale

Thursday, January 24, 2013

Emotional Memories & Genes


Generally, emotion helps us remember (Reisberg, 2010).  Emotional events activate the amygdala, and various studies, show the amygdala (region of brain that coordinates autonomic and endocrine responses in conjunction with emotional states) plays a key role in enhancing explicit memory (conscious, declarative) for both pleasant and unpleasant emotional stimuli through modulation of encoding and consolidation processes (Hamman, 2001).  In addition to activation of the amygdala, emotional events are likely to be important to us, which leads to enhanced focused attention, thus facilitating memory.  Moreover, we often think about emotional events hours, days or weeks after they occur.  This type of memory rehearsal may lead to increased memory connections, enhancing the likelihood of retrieval.  

Genes and Memory

Eric Kandel, Nobel Laureate, suggests another means in which emotional events may contribute to enhanced and efficient memory.  Generally, repetition is required for the formation of long-term memory.  However, a highly emotional event, such as a life-threatening situation, could bypass the normal limits on long-term memory (Kandel, 2006). 

“In such a situation, enough MAP kinase molecules would be sent into the nucleus rapidly enough to inactivate CREB-2 molecules, thereby making it easy for protein Kinase [enzyme that adds a phosphate group to proteins, which activates some proteins and inactivates others] A to activate CREB-1 and put the experience directly into long-term memory.”
(Kandel, 2006, pp. 264-265)

The extraordinary memory shown by some people may be due to genetic differences in CREB-2 that limit the activity of this repressor protein in relation to CREB-1.  CREB-1 is a protein that activates expression of CREB – a gene that initiates protein synthesis that is essential for the storage of long-term memory.  CREB-2 is a protein that suppresses the expression of CREB.  Other genes as well as CREB have been found to influence memory (Kandel, 2006).  Kandel’s work has been mostly focused on CREB- dependent gene expression.

“[O] ther transcription factors, such as SRF, c-fos, EGR-1 or NF-κB are also likely to contribute to the transcriptional regulation that accompanies long-lasting forms of synaptic plasticity for different forms of learning in different animal species.” (Kandel, 2012, 14)   

CREB-1 and CREB-2 may be involved in age related memory loss.  Aging may represent a weakening of the ability to activate CREB-1, but also a weakening of the signals needed to stop the action of CREB-2. 

When I first watched the video below I assumed that Jill Price may have some abnormalities in gene expression

The Woman Who Could Not Forget





An article featured in Wire paints a different picture of Jill’s superb memory.


 References

Hamann, S. (2001).  Cognitive and neural mechanisms of emotional memory.  Trends in Cognitive Sciences, 5 (9), 394-400.

Kandel, E. (2006).  In Search of Memory: The Emergence of A New Science of Mind.  New York: W.W. Norton & Company. 

Kandel, E. (2012).  The molecular biology of memory: cAMP, PKA, CRE, CREB-1, CREB-2, and CPEB.  Molecular Brain, 5,14.   

Reisberg, D. (2010).  Cognition: Exploring The Science of The Mind 4th Edition.  New York: W.W. Norton & Company.