Your brain is no dummy. It practices “energy conservation.” It learns as you learn. When you use the same memory over and over, each time you call it up, it greases the skids for it to come up the next time. Use facilitates future use. In Guyton’s Textbook of Medical Physiology, he describes this process by writing, “. . . each time certain types of sensory signals pass through sequences of synapses (nerve connections), these synapses become more capable of transmitting the same signals the next time. . .” He calls this “facilitation.” This concept will come as no surprise to anyone who has had to memorize poems, math facts, formulas, or even the attributes of company products.

The frequency and ease with which you resurrect memories is important to why memories can dramatically impact your health.

Experiences gathered throughout your life are stored in memories. Each minute of each day, you compare current experiences with those of past seconds, yesterdays, and yesteryears, and your physiology responds accordingly. A loud bang is compared with memories of other bangs to determine if you hear an explosion or a plate breaking. A harsh voice is compared with memories of an abusive parent or with memories of personally non-threatening dialogue from a movie scene. No matter how you respond outwardly to your experiences, the memories that prompt your responses are uniquely personal.

Memories of your life experiences and your responses to these experiences are all carefully filed away in various areas of your brain for reference. The memories act as a template to compare stimuli from current events with events that were similar in the past. Each of us has compiled his or her own mental collage of life experiences, memories, and outward responses to situations and the instructions for internal physiological responses. The more intense or impressive the situation that formed the memory, the more strongly embedded the instructions for physiological responses to that memory. These physiological responses are part of the standard survival system. Although memories are neither good nor bad (they are your personal resource encyclopedia), the physiological response instructions accompanying the memories are always perfect for the situation when the memory was initially stored. The glitch comes when the memory keeps prompting the same physiological response long after the incident is over. And the glue that sticks physiological responses to memories is intense feelings and emotions.

Since you have no direct control over the physiological responses your body will make to any message, your best bet for health is to ensure the internal messages concern short-term current circumstances – not lingering outdated feelings and emotions stored along with memories of past events.