A study by Duke University researchers provides insight into how the ability to inhibit an action affects important brain functions, such as memory. Researchers suggest this may even lead to an increased understanding of ADHD.
The human brain has a sophisticated ability scientists have dubbed “response inhibition.” This allows people to cancel actions even if it is something ingrained or reflexive. This is why certain deep-seated habits—like the side of the road someone drives on—can be overwritten in certain scenarios.
For the study, participants were instructed to press a button if they saw a male face but not if they saw a female face, and vice-versa. Once 120 faces had been shown, an unrelated task was performed before participants were given a surprise memory test. They were shown faces and asked if it was a new face or one they were shown from the task. Initially, the researchers didn’t know what to expect. From what they understood, it was just as likely that the urgent need to inhibit a response (the button press) would have ingrained a face more clearly memory as it would not have.
Researchers discovered that participants had more difficulty remembering the faces that they had to inhibit the “button press” for. The next step was to understand why.
Brain scans showed that when a face someone forgot was being shown, one of the brain’s known inhibition networks was highly active. In addition, the scans showed that areas known to activate when a memory is being encoded were less active when a participant had to quickly inhibit the button press.
This give-and-take relationship between inhibition and memory may explain why children with ADHD have trouble focusing. As the child tries to block their urge to fidget, they also impair their ability to recall information. The link is purely speculative at this stage, and a more specific study would be required to confirm or refute its findings.
The Duke University team, led by Tobias Egner and Yu-Chin Chiu, has moved on to examine how other forms of self-control, such as rapidly changing tasks, can affect memory as well.
Source for Today’s Article:
Chiu, Y., et al., “Inhibition-Induced Forgetting Results from Resource Competition between Response Inhibition and Memory Encoding Processes,” The Journal of Neuroscience 2015; 35(34): 11936–11945, doi: 10.1523/JNEUROSCI.0519-15.2015.