From Decay to Interference; Why We Forget

Unlike the computer hard drive, which “remembers” things until they’re overwritten by new data, the human brain is capable of forgetting. As far back as 1885, a man named Hermann Ebbinghaus performed an experiment on himself that involved memorizing nonsense syllables and recording his ability to remember them over time. You’ve almost certainly seen some form of the Ebbinghaus “forgetting curve” if you’re a sales trainer. But what causes us to forget? Contemporary research indicates that two processes, decay and interference, are responsible.

The Decay Phenomenon

Decay can be envisioned like words written into the sand at the ocean’s edge. As waves wash over the words with time, they fade out until they’re completely gone. Only with memory decay, the brain cells are the sand and time is the ocean wave washing over it. Memory decay happens when time passes during which memories have not been accessed. The brain really does have a “use it or lose it” tendency, and when memories and things learned are not reinforced and recalled, those neural pathways tend to lose strength over time.

What does this mean to the sales trainer? First, you must know people’s jobs and how new knowledge is to be applied. Second, you and your learners must understand that regular use and recall of information can prevent memory decay.

The Phenomenon of Interference

If you learn, say, a song, and then soon after learn another song with a similar melody or rhythm, your brain can meld the two to some extent, making it more challenging to separate them mentally. Interference is the forgetting phenomenon where memories become less accessible because the acquisition of similar information interferes with it. Instead of words written into sand being washed out gradually, you can imagine writing something down, then scribbling over it. Suddenly it’s hard to discern one from the other.

Interference is a form of “overwriting” memories so that they become difficult to impossible to remember correctly. Typically, things that are learned specifically to be applied in a defined context are subject to interference. One important way sales trainers can guard against interference-related forgetting is to provide easy-access information resources that learners can reference when they need to.

Familiarity, Recollection, and Why We Forget

There are two basic types of explicit memory: familiarity and recollection. Familiarity is the vaguer of the two. In other words, that person looks familiar, but you can’t place them or remember their name. Or perhaps you know “of” something, but not the thing itself. Say you remember reading about the Alternative Minimum Tax, but you don’t specifically know who is most likely to be affected by it. That’s familiarity.

Recollection is more fine-tuned because it’s the recovery of specific details along with their context. For example, you know that if you want your dinner roast to turn out tender, you need to select the right cut of meat and cook it slowly at a relatively low temperature, whereas if you’re stir-frying vegetables, you want high heat for a short amount of time.

Memories based on familiarity and memories based on recollection are stored differently by the brain. Recollection is more resistant to the interference phenomenon. Unfortunately, it is less resistant to decay. This is why you can be really good at something but get “out of practice” over time.

Sales Training Strategies Can Affect Remembering

The “experience” you have of something is physically represented by a pulse of electrical energy traveling through a network of neurons. When you first experience something, the experience is stored in short-term memory, where it will reside for up to a few minutes. At that point, the experience may be transferred to long-term memory regions of the brain. One such region is the hippocampus, which is the part of the brain associated with emotion, and which can direct memories to be stored in various parts of the brain.

If the neurons associated with the experience communicate regularly and repeatedly, the synapses between them become more efficient in a process called long-term potentiation, which is how memories become stored for the long term. Embedding of memories into long term storage is most likely to happen when we’re actively paying attention and engaged in the learning process, and when the information has personal meaning to us.

Sales Training and the “Tides” of Learning

Organizations have to adapt their training programs over time. Technologies, learners, society, and customers all evolve, and learning has to do the same. A phenomenon called “organizational oscillation” is one explanation for why organizations shift from periods of learning to periods of forgetting. It makes sense if you think about it. Suppose your organization has a long period of time without a workplace injury. While this indicates you’re doing many things right, it can also lead to a certain complacency, something it will snap out of quickly as soon as a workplace injury occurs. At that point, a focus on workplace safety may replace an organizational focus on, say, energy conservation or some other concept.

In other words, errors are disruptive. This affects pharmaceutical companies somewhat differently than it does steel mills, but it’s something to be aware of. A long-term study, for example, that indicates a problem with a drug can rapidly shift organizational focus, affecting training programs and how sales reps perform their jobs.

Forgetting is affected by the simple passage of time, and by new information that interferes with information we’ve already taken in. Forgetting also depends upon how and where memories are stored in the brain. The dual phenomena of decay and interference indicate that our brains aren’t “hardwired,” but that messages are “written” and accessed differently with the passage of time. Awareness of the roots of forgetting can help the pharmaceutical sales trainer develop training programs designed to prevent forgetting by including sufficient recall and testing to solidify learning. We encourage you to browse our blog for more information on the science of learning.