The Art of Unlearning

I've been studying neuroscience recently and I believe one of the foundational aspects of how our brain works is its ability to establish correlations. At a very basic level, one of the ways we learn seems to be the establishment of a connection between two or more objects, attributes, events, ideas, etc. Biologically, the synapses, or connections between neurons, are strengthened or weakened based on several mechanisms. The neuroscience community calls this elastic phenomenon 'synaptic plasticity' and it is believed to be an important mechanism by which we learn.

Pavlov's dogs are a good example of this phenomenon. Through repeated experiences, they learned that there was a correlation between the ringing of a bell and feeding time. In their minds, they correlated these two events over time such that one event (the ringing of the bell) would trigger physiological reactions (e.g. salivation) that indicated they expected the second event.

This seems to be why we often require repeated exposure to ideas in order to learn them. The synaptic plasticity doesn't occur with a single exposure to two ideas; it evolves over time as those experiences are repeated. Learning by repetition works really well for my kids and I think that's pretty universal.

So I got to thinking about the idea of 'unlearning' and I think it's a bit harder to do than learning. If learning is, at least in part, fundamentally the establishment of correlations, then one way to unlearn something is to break correlations, but that's not exactly a straightforward thing to do.

Suppose I have been building correlations all my life that connect a certain habit to various stimuli. Let's say I like to smoke. Every time I smoke a cigarette, I'm experiencing new visual, auditory, and olfactory stimuli. These stimuli can become correlated in my brain with the stimuli associated with smoking. Over time, a certain image, sound, or smell or even the thought of one of those stimuli can trigger the thought of smoking. If I have made it a habit, then my brain tends to reinforce the action with random sensory inputs that are correlated with the experience of smoking.

In the case of nicotine and other drugs, they actually modulate certain neuro-chemical processes in the brain by blocking or enhancing the reception of neurotransmitters, which makes them even more addictive than an ordinary, less brain-invasive habit. But the concept is the same. Habits and thought patterns can be triggered by association with other ideas and sensory inputs to the brain. Breaking a habit or unlearning a correlation is a lot harder than creating a habit or establishing a correlation.

Instead of associating ideas, to unlearn something, we have to disassociate them, which requires breaking correlations that have been embedded in the mind. I've found many times that I've had to unlearn things I had come to believe as a child or a young man. Some associations were formulated at school, some at home, and some who knows where. I imagine most people face this at one time or another.

I'm not sure I have a good formula for unlearning, but just as correlations are built with repeated associations, perhaps we can decorrelate ideas by thinking about one of the ideas and actively suppressing the other idea. If we repeatedly expose ourselves to cases where one idea is present and the other is suppressed, perhaps the brain will respond by weakening synaptic connections that were previously strengthened and over time, we won't automatically think of the second idea when presented with the first.

This seems like a really important skill to learn. Some people seem to become more closed-minded as they age leaving an unmalleable mind in a 70 year old. Keeping our minds open and flexible requires regular exercise, which requires the humility to admit that we'll always have a lot to learn. I think we also have to find joy in the learning process and be willing to undertake the effort to unlearn ideas we previously cherished when we find them incompatible with truth. In the words of the great Yoda, "[we] must unlearn what [we] have learned."