The Past that Pretends to be the Present 

This month I want to give a quick overview of the difference between “implicit” and “explicit” memory, which is really a critical one both for dealing with depression and anxiety, and, well, just for the challenge of being human.  I hav  e found that it can help us make sense of what otherwise is baffling in our experience, those moments of, “Why am I doing this?”
“Implicit memory” is defined as (to paraphrase Dan Siegel in the “Pocket Guide to Interpersonal Neurobiology”) the memory system that is able to encode information without needing a person to focus and direct attention, and which, when that information arises again (is retrieved, like retrieving data in a computer), there is not a label or sense that says, “This is a memory.”  It is the memory system that comes online first in infant development, and because it gets its start before language, the “information” of these memories are coded in body sensation and emotions, what the infant has to make sense of the world before symbolic language is available.

“Explicit memory” is what we’re most used to in calling memory, being the encoding of information into memory that requires the focusing of attention and when it arises, is labeled or sensed as “This is a memory.”  If you think about what it was like to go shopping last week, that’s an explicit memory.  If you feel a wash of sadness without any immediate cause or association, that could likely be an implicit memory, a recalling of what you actually experienced when very young.

While implicit memory is very important for learning the basics of survival and acting out of those quickly (without the relatively slow processes of explicit memory), it is problematic because it allows experience to get recorded below our conscious radar, and because, without a “This is memory” label, they often get confused with present tense experiences.

For example: Say I’m making dinner with my wife and as she’s cutting the carrots, I get a pang of anxiety. Now, she’s never cut herself and is a careful person, yet I feel like something dangerous is going to happen. And because I’m scared, my fight or flight system gets activated, and I’m being “told,” internally, that I need to address a threat. So I shout, “You need to be careful.  You’re going to cut yourself.” She frowns, of course, because she’s not registering any threat, but that only makes me more anxious, and now mad that I’m not being listened to around what’s obviously a danger.  So begins a fight..

What I’m not aware of in the moment (which I might clarify and understand later through introspection or therapy) is that as I’m watching my wife use the knife, an implicit memory surfaces, an encoding of an experience of being a young child playing in the kitchen while my mother is chopping vegetables.  She slips and slices her hand, and suddenly she’s screaming, and then the others in the house are scared, and I’m lost track of while having to feel all the fear and tension alone.  I don’t remember the experience as an explicit memory (“There was that time when Mom…”), but rather as the essential elements: kitchen, knife, important female, sudden shock, being abandoned.  The template is all there for my 40 year old self to remember my 2 year old self’s experience, but without being able to identify my experience in the present as a recall–an actual memory–then my rational left brain, in its need to understand, says, “This is happening now!  There is a danger!”  And given it’s intensity (because it was so intense at age 2), it’s hard to ignore or to be mindful of, hard because my system has gone into danger management mode–just fix it now!

Animals, presumably, have just the implicit memory system, whereas humans have a more complicated explicit memory in addition, and the two are often at odds (as in the example).  The work of psychotherapy, in a way, has much to do with addressing and mitigating this tension, between the unlocated and located “knowns” of our lives.

Even just understanding conceptually that there are these two systems of memory can be helpful in answering the question, “Why did I do that?”  Even just recognizing that, “Oh, this could be one of those implicit memories,” without knowing the exact situation that is being recalled, can short circuit the rational mind’s insistence that, if we’re feeling this way, and we can’t identify it as a memory, then it must be about the present circumstance.  Knowing that that’s not always true allows more flexibility to hold more lightly the meaning of any particular experience we’re having.

Which, with anxiety and depression, is doubly important because they are both states of mind that are insistent on blunt realities:  “I am in danger!” and, “This all is futile!”  In a large way, resilience and flexibility are both curatives and products of healing from these wild moods, and knowing there are such things as different memory systems, with different natures, can help with increasing that flexibility.