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.
Frontal theta activity and white matter plasticity following mindfulness meditation.
Curr Opin Psychol. 2019 Apr 18;28:294-297
Authors: Tang YY, Tang R, Rothbart MK, Posner MI
Both brain alpha and theta power have been examined in the mindfulness meditation literature and suggested as key biological signatures that potentially facilitate a successful meditative state. However, the exact role of how alpha and theta waves contribute to the initiation and maintenance of a meditative state remains elusive. In this perspective paper, we discuss the role of frontal midline theta (FMθ) activity in brain white matter plasticity following mindfulness meditation. In accordance with the previous studies in humans, we propose that FMθ activity indexes the control needed to maintain the meditation state; whereas alpha activity is related to the preparation needed to achieve the meditative state. Without enough mental preparation, one often struggles with and has difficulty achieving a meditative state. Animal work provides further evidence supporting the hypothesis that mindfulness meditation induces white matter changes through increasing FMθ activity. These studies shed light on how to effectively enhance brain plasticity through mindfulness meditation.
PMID: 31082635 [PubMed - as supplied by publisher]
Rehabilitating the brain through meditation and electrical stimulation.
Cortex. 2018 Aug 31;:
Authors: Posner MI
This paper is a review of our recent studies and ideas related to the neuropsychological issues that Robert Rafal and I worked together to understand attention and hopefully improve it in a variety of patients. Rehabilitation is also a goal of my current research to determine if non invasive stimuli can improve white matter in humans. We have found that fractional anisotropy (FA) is improved in pathways surrounding the anterior cingulate cortex (ACC) following two week to four weeks of meditation training. We hypothesized that the frontal theta increased following meditation training might be a cause of the improved connectivity. This was confirmed by a mouse study using optogenetics to impose theta rhythms in the ACC. We have evidence that electrical stimulation while performing a task that activates the ACC can also increase theta. We plan studies to determine whether two to four weeks of stimulation can improve FA in pathways surrounding the anterior cingulate.
PMID: 30245201 [PubMed - as supplied by publisher]
Changes in white matter in mice resulting from low-frequency brain stimulation.
Proc Natl Acad Sci U S A. 2018 07 03;115(27):E6339-E6346
Authors: Piscopo DM, Weible AP, Rothbart MK, Posner MI, Niell CM
Recent reports have begun to elucidate mechanisms by which learning and experience produce white matter changes in the brain. We previously reported changes in white matter surrounding the anterior cingulate cortex in humans after 2-4 weeks of meditation training. We further found that low-frequency optogenetic stimulation of the anterior cingulate in mice increased time spent in the light in a light/dark box paradigm, suggesting decreased anxiety similar to what is observed following meditation training. Here, we investigated the impact of this stimulation at the cellular level. We found that laser stimulation in the range of 1-8 Hz results in changes to subcortical white matter projection fibers in the corpus callosum. Specifically, stimulation resulted in increased oligodendrocyte proliferation, accompanied by a decrease in the g-ratio within the corpus callosum underlying the anterior cingulate cortex. These results suggest that low-frequency stimulation can result in activity-dependent remodeling of myelin, giving rise to enhanced connectivity and altered behavior.
PMID: 29915074 [PubMed - indexed for MEDLINE]
Temperament and brain networks of attention.
Philos Trans R Soc Lond B Biol Sci. 2018 04 19;373(1744):
Authors: Posner MI, Rothbart MK
The attention networks of the human brain are important control systems that develop from infancy into adulthood. While they are common to everyone, they differ in efficiency, forming the basis of individual differences in attention. We have developed methods for measuring the efficiency of these networks in older children and adults and have also examined their development from infancy. During infancy the alerting and orienting networks are dominant in control of the infant's actions, but later an executive network dominates. Each network has been associated with its main neuromodulator and these have led to associations with genes related to that network neuromodulator. The links between parent reports of their child's effortful control and the executive attention network allow us to associate molecular mechanisms to fundamental behavioural outcomes.This article is part of the theme issue 'Diverse perspectives on diversity: multi-disciplinary approaches to taxonomies of individual differences'.
PMID: 29483356 [PubMed - indexed for MEDLINE]
Diversity in action: exchange of perspectives and reflections on taxonomies of individual differences.
Philos Trans R Soc Lond B Biol Sci. 2018 04 19;373(1744):
Authors: Uher J, Trofimova I, Sulis W, Netter P, Pessoa L, Posner MI, Rothbart MK, Rusalov V, Peterson IT, Schmidt LA
Throughout the last 2500 years, the classification of individual differences in healthy people and their extreme expressions in mental disorders has remained one of the most difficult challenges in science that affects our ability to explore individuals' functioning, underlying psychobiological processes and pathways of development. To facilitate analyses of the principles required for studying individual differences, this theme issue brought together prominent scholars from diverse backgrounds of which many bring unique combinations of cross-disciplinary experiences and perspectives that help establish connections and promote exchange across disciplines. This final paper presents brief commentaries of some of our authors and further scholars exchanging perspectives and reflecting on the contributions of this theme issue.This article is part of the theme issue 'Diverse perspectives on diversity: multi-disciplinary approaches to taxonomies of individual differences'.
PMID: 29483355 [PubMed - indexed for MEDLINE]
Rhythmic brain stimulation reduces anxiety-related behavior in a mouse model based on meditation training.
Proc Natl Acad Sci U S A. 2017 03 07;114(10):2532-2537
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 - indexed for MEDLINE]
Developing brain networks of attention.
Curr Opin Pediatr. 2016 12;28(6):720-724
Authors: Posner MI, Rothbart MK, Voelker P
PURPOSE OF REVIEW: Attention is a primary cognitive function critical for perception, language, and memory. We provide an update on brain networks related to attention, their development, training, and pathologies.
RECENT FINDINGS: An executive attention network, also called the cingulo-opercular network, allows voluntary control of behavior in accordance with goals. Individual differences among children in self-regulation have been measured by a higher order factor called effortful control, which is related to the executive network and to the size of the anterior cingulate cortex.
SUMMARY: Brain networks of attention arise in infancy and are related to individual differences, including pathology during childhood. Methods of training attention may improve performance and ameliorate pathology.
PMID: 27552068 [PubMed - indexed for MEDLINE]
White matter and reaction time: Reply to commentaries.
Cogn Neurosci. 2017 Apr;8(2):137-140
Authors: Voelker P, Piscopo D, Weible AP, Lynch G, Rothbart MK, Posner MI, Niell CM
We appreciate the many comments we received on our discussion paper and believe that they reflect a recognition of the importance of this topic worldwide. We point out in this reply that there appears to be a confusion between the role of oscillations in creating white matter and other functions of oscillations in communicating between neural areas during task performance or at rest. We also discuss some mechanisms other than the enhancement of white matter that must influence reaction time. We recognize the limited understanding we have of transfer and outline some future directions designed to improve our understanding of this process.
PMID: 27400280 [PubMed - in process]