Professor Emeritus, Department of Psychology
Ph.D. University of Michigan
M.S. University of Washington
B.S. University of Washington
Research Interests: Cognitive-Neuroscience; Neural mechanisms and structures underlying selective attention
Overview: Michael Posner is Professor Emeritus at the University of Oregon and Adjunct Professor at the Weill Medical College in New York (Sackler Institute).
Dr. Posner's current work deals with genetic and experiential factors in the development of brain networks underlying attention and learning. We are currently examining how changes in white matter might contribute to improved performance. In one study conducted together with the Niell lab we are imposing a theta rhythm on cells in the anterior cingulate of the mouse and examining whether the resultant activity leads to improved myelination in pathways near the cingulate. We are also examining if epigenetic factors related to methylation might account for individual differences in this process.
Rhythmic brain stimulation reduces anxiety-related behavior in a mouse model based on meditation training.
Proc Natl Acad Sci U S A. 2017 Feb 21;:
Authors: Weible AP, Piscopo DM, Rothbart MK, Posner MI, Niell CM
Meditation training induces changes at both the behavioral and neural levels. A month of meditation training can reduce self-reported anxiety and other dimensions of negative affect. It also can change white matter as measured by diffusion tensor imaging and increase resting-state midline frontal theta activity. The current study tests the hypothesis that imposing rhythms in the mouse anterior cingulate cortex (ACC), by using optogenetics to induce oscillations in activity, can produce behavioral changes. Mice were randomly assigned to groups and were given twenty 30-min sessions of light pulses delivered at 1, 8, or 40 Hz over 4 wk or were assigned to a no-laser control condition. Before and after the month all mice were administered a battery of behavioral tests. In the light/dark box, mice receiving cortical stimulation had more light-side entries, spent more time in the light, and made more vertical rears than mice receiving rhythmic cortical suppression or no manipulation. These effects on light/dark box exploratory behaviors are associated with reduced anxiety and were most pronounced following stimulation at 1 and 8 Hz. No effects were seen related to basic motor behavior or exploration during tests of novel object and location recognition. These data support a relationship between lower-frequency oscillations in the mouse ACC and the expression of anxiety-related behaviors, potentially analogous to effects seen with human practitioners of some forms of meditation.
PMID: 28223484 [PubMed - as supplied by publisher]