May 3, 2024

The Brain’s Alarm System To Suppress Intrusive Thoughts and Inhibit Unwanted Memories

By Society for Neuroscience
April 18, 2022

New research study reveals that to reduce invasive thoughts, the brain utilizes an alarm that signals other regions to hinder them.
A brain region can proactively and reactively spot the need to inhibit undesirable memories.
Forget what you saw: a brain area finds when you will think about an undesirable memory and alerts other areas to reduce it, according to research released in JNeurosci today (April 18, 2022). JNeurosci is the Society for Neurosciences first journal.
A design of how the ACC proactively and reactively indicates the need for thought suppression. Credit: Crespo García et al., JNeurosci 2022
Crespo García et al. measured individuals brain activity with both EEG and fMRI while they finished a memory task. The participants remembered sets of words (i.e., gate and train) and were asked to either remember a cue words set (see gate, consider train) or only focus on the cue word (see gate, only consider gate).
During proactive memory suppression, activity increased in the anterior cingulate cortex (ACC), a brain area associated with cognitive control, within the first 500 milliseconds of the job. The ACC relayed details to the dorsolateral prefrontal cortex (DLPFC), which then prevented activity in the hippocampus, a key area for memory recall.

The activity levels in the ACC and DLPFC remained low for the rest of the trial, an indication of success– the memory was stopped early enough so say goodbye to suppression was required. If the memory was not reduced in time, the ACC produced a reactive alarm, increasing its activity to signify to the DLPFC to stop the invasion.
Referral: “Anterior Cingulate Cortex Signals the Need to Control Intrusive Thoughts During Motivated Forgetting” 18 April 2022, JNeurosci.DOI: 10.1523/ JNEUROSCI.1711-21.2022.