New research published in Nature Neuroscience has shed light on how the brain filters out distractions during memory formation. A type of synaptic plasticity called long-term changes in inhibitory connections between neurons helps suppress irrelevant sensory input during memory replay, a process believed to support long-term learning.
The study aimed to understand how the brain distinguishes between useful and irrelevant information when storing memories. Researchers used computational models and experimental methods in mice to investigate this question. They found that including inhibitory plasticity allowed the network to suppress activity of neurons tuned to unpredictable stimuli while reinforcing patterns that reflected stable aspects of the environment.
In optogenetic experiments, researchers created artificial “distractor cells” by pairing random sensory cues with artificial stimulation of specific neurons. Later, they measured whether these neurons were suppressed during memory replay and found that increased inhibitory input onto these neurons was linked to reduced activation.
The study suggests that inhibitory learning is essential for filtering distractions and forming coherent memories. When inhibitory plasticity was removed or disrupted, the brain’s ability to distinguish signal from noise broke down, leading to cluttered and structured representations.
While the study provides strong support for the role of inhibitory plasticity in memory consolidation, it also has limitations. Future research could explore how different types of inhibitory neurons contribute to memory selection and whether this mechanism applies in other brain regions or during sleep.
Source: https://www.psypost.org/neuroscientists-discover-biological-mechanism-that-helps-the-brain-ignore-irrelevant-information