Dr. Michael Posner collaborated with members of the Biology Department and the Institute of Neuroscience (ION) on a recently published paper about attention and memory*. They found that mice and humans both use connections between attention networks and memory networks in the learning of new skills.
This collaboration began seven years ago, when Posner gave a talk on changing the connectivity of white matter in the brain with meditation training. He speculated that increasing a specific type of brain wave, theta, can induce white matter change. Dr. Cristopher Niell, a member of the biology department and ION, approached Posner after the talk and explained that he could help test Posner’s theory with mice. This interaction has led to a fruitful collaboration and many published papers, including this most recent one.
Posner worked with Niell and several members of the psychology department and ION (Aldis Weible, Pascale Voelker, and Mary K. Rothbart) to figure out how attention and memory networks interact while learning a skill. To investigate this, they trained mice to follow nonintuitive cues. A cue at the bottom of the screen meant they had to go right and a cue at the top meant they had to go left. These cues are known as “incompatible associations” in human research and they introduce a conflict into decision-making, because we don’t associate “left” with “up” in our daily lives. To assess how the attention and memory networks impact learning, they used optogenetics to suppress the hippocampus (HC), a major memory area of the brain involved with learning associations, and the anterior cingulate cortex (ACC), an area of the brain involved with executive attention. They found that suppressing either area reduced the accuracy of the task, especially the ACC.
Next, they reviewed the literature to determine if these findings are reflected in human studies. Based on what they found in the literature, they hypothesized that there may be two major pathways between the attention network (ACC) and the memory network (HC). Pathway 1, which goes through the thalamus, relates to generalizing knowledge to other contexts and controlling conflict, which explains why suppressing the ACC in their conflict task significantly reduced accuracy. Pathway 2, which goes through the entorhinal cortex and the parietal lobe, relates to how people orient their attention and give primacy to location.
Posner hopes to improve the connectivity of these pathways using neuromodulation, electrical stimulation to specific parts of the brain. Although neuromodulation has failed in many other studies, Posner has used it successfully with mice and hopes that it will become more successful with humans. Improving the pathways between the memory (HC) and attention (ACC) networks could improve their function, resulting in improved skill learning. In the long run, learning how to change and repair white matter in the brain could help people recover from concussions and multiple sclerosis.
The collaborative nature of this project, drawing on expertise in cognitive psychology, neuroscience, and biology, moved it in fresh directions. It’s unusual in the field to examine human data in light of mice data, but, for Posner and his colleagues, this approach produced a lot of insight. Working with Niell also allowed Posner to examine subcortical parts of the brain, which are understudied in Cognitive Neuroscience due to methodological difficulties. Niell’s perspective was also instrumental in interpreting and studying the directionality of the pathways. Overall, Posner appreciated the chance to learn from and work with such great researchers.
* Posner, M.I., Weible, A.P., Voelker, P., Rothbart, M.K. & Niell, C.M. (2022) Decision Making as a Learned Skill in Mice and Humans Frontiers in Neuroscience 16:834701.doi: 10.3389/fnins.2022.834701