Neuroscience – Page 5 – The Miller Lab @ MIT

25

Jan 2018

New paper: Different Levels of Category Abstraction by Different Dynamics in Different Prefrontal Areas

Miller Lab

Miller Laboratory, Neuroscience

Wutz, A., Loonis, R., Roy, J.E., Donoghue, J.A., and Miller, E.K. (2018) Different levels of category abstraction by different dynamics in different prefrontal areas. Neuron published online Jan 25 2018.

SUMMARY

Categories can be grouped by shared sensory attributes (i.e. cats) or by a more abstract rule (i.e. animals). We explored the neural basis of abstraction by recording from multi-electrode arrays in prefrontal cortex (PFC) while monkeys performed a dot-pattern categorization task. Category abstraction was varied by the degree of exemplar distortion from the prototype pattern. Different dynamics in different PFC regions processed different levels of category abstraction. Bottom-up dynamics (stimulus-locked gamma power and spiking) in ventral PFC processed more low-level abstractions whereas top-down dynamics (beta power and beta spike-LFP coherence) in dorsal PFC processed more high-level abstractions. Our results suggest a two-stage, rhythm-based model for abstracting categories.
18

Jan 2018

Anterior Cingulate Cortex Input to the Claustrum Is Required for Top-Down Action Control

Miller Lab

Neuroscience

A new addition to the proposed circuitry for top-down control.

White, M. G., Panicker, M., Mu, C., Carter, A. M., Roberts, B. M., Dharmasri, P. A., & Mathur, B. N. (2018). Anterior Cingulate Cortex Input to the Claustrum Is Required for Top-Down Action Control. Cell reports, 22(1), 84-95.
17

Jan 2018

Dopamine Is Signaled by Mid-frequency Oscillations and Boosts Output Layers Visual Information in Visual Cortex

Miller Lab

Neuroscience

The authors find that dopamine increased power of beta-low gamma oscillations in cortex. During visual stimulation, dopamine increased information encoding over a wide range of frequencies but most prominently in the feedforward supragranular layers and in the gamma band (50-100 Hz).

Zaldivar, D., Goense, J., Lowe, S. C., Logothetis, N. K., & Panzeri, S. (2018). Dopamine Is Signaled by Mid-frequency Oscillations and Boosts Output Layers Visual Information in Visual Cortex. Current Biology.

This must be correct. It is very remarkably consistent with our recent study 🙂
Bastos, A.M., Loonis, R., Kornblith, S., Lundqvist, M., and Miller, E.K. (2018) Laminar recordings in frontal cortex suggest distinct layers for maintenance and control of working memory. Proceedings of the National Academy of Sciences. doi:10.1073/pnas.1710323115 View PDF

as well as with our previous work showing that gamma is associated with bottom-up processing:
Buschman, T.J. and Miller, E.K. (2007) Top-down versus bottom-up control of attention in the prefrontal and posterior parietal cortices. Science. 315: 1860-1862 View PDF »
16

Jan 2018

Our new model of working memory as illustrated by Charles Mingus and Miles Davis

Miller Lab

Miller Laboratory, Neuroscience

High frequency waves (Davis on trumpet) carry sensory inputs from the back of the brain to the front. Low frequency waves (Mingus on bass) carry executive (top-down) information from the front to the back of the brain. The low frequencies control the expression of high frequencies. That’s how you choose what sensory inputs to hold in mind (working memory). (Image: Andre Bastos)

It makes sense because we all know that the bass should guide the lead instruments. Am I right?

Bastos, A.M., Loonis, R., Kornblith, S., Lundqvist, M., and Miller, E.K. (2018) Laminar recordings in frontal cortex suggest distinct layers for maintenance and control of working memory. Proceedings of the National Academy of Sciences. published ahead of print January 16, 2018, doi:10.1073/pnas.1710323115

Read MIT press release here.
9

Jan 2018

Persistent neuronal activity in human prefrontal cortex links perception and action

Miller Lab

Neuroscience

Persistent activity (indexed by broadband gamma) across human cortex encodes stimulus features and predicts motor output.

Haller, Matar, John Case, Nathan E. Crone, Edward F. Chang, David King-Stephens, Kenneth D. Laxer, Peter B. Weber, Josef Parvizi, Robert T. Knight, and Avgusta Y. Shestyuk. “Persistent neuronal activity in human prefrontal cortex links perception and action.” Nature Human Behaviour (2017): 1.

But how persistent is it?
Lundqvist, M., Rose, J., Herman, P, Brincat, S.L, Buschman, T.J., and Miller, E.K. (2016) Gamma and beta bursts underlie working memory. Neuron, published online March 17, 2016. View PDF »
9

Jan 2018

Feedback from human posterior parietal cortex enables visuospatial category representations as early as primary visual cortex

Miller Lab

Neuroscience

Coarse visuospatial categories are represented in the posterior parietal cortex whereas fine-scale discrimination are in primary visual cortex with the latter depending on feedback from the former.

Li, Y., Hu, X., Yu, Y., Zhao, K., Saalmann, Y. B., & Wang, L. (2017). Feedback from human posterior parietal cortex enables visuospatial category representations as early as primary visual cortex. Brain and Behavior.
9

Jan 2018

Electrical stimulation of macaque lateral prefrontal cortex modulates oculomotor behavior indicative of a disruption of top-down attention

Miller Lab

Neuroscience

The authors report different effects of stimulation of the lateral prefrontal cortex. Stimulation at or near the FEF prolonged or decreased saccade reaction time, depending on task instructions. More rostral stimulation affected the attention weighting of saccade targets.

Schwedhelm, P., Baldauf, D., & Treue, S. (2017). Electrical stimulation of macaque lateral prefrontal cortex modulates oculomotor behavior indicative of a disruption of top-down attention. Scientific reports, 7(1), 17715.
3

Jan 2018

Three new papers in press

Miller Lab

Miller Laboratory, Neuroscience

Gamma and beta bursts during working memory readout suggest roles in its volitional control
Lundqvist et al Nature Communications, in press.

Laminar recordings in frontal cortex suggest distinct layers for maintenance and control of working memory
Bastos et al PNAS, in press

Different levels of category abstraction by different dynamics in different prefrontal areas
Wutz et al Neuron, in press

Stay tuned for what they are about and what they mean. They add up to a new model of working memory.
20

Dec 2017

New paper accepted: “Laminar recordings in frontal cortex suggest distinct layers for maintenance and control of working memory”

Miller Lab

Miller Laboratory, Neuroscience

New paper accepted:

“Laminar recordings in frontal cortex suggest distinct layers for maintenance and control of working memory”

Bastos, Loonis, Kornblith, Lundqvist, and Miller. PNAS, in press

Coming soon. Stay tuned.
20

Dec 2017

A Neural Model of Working Memory

Miller Lab

Neuroscience

The authors suggest a hybrid model of working memory. The current focus of attention is encoded by spiking activity. Other items held in the working memory that are not the current focus of attention are held by temporary changes in synaptic weights per the activity-silent models of Lundqvist and Stokes.

Manohar, S. G., Zokaei, N., Fallon, S. J., Vogels, T., & Husain, M. (2017). A neural model of working memory. bioRxiv, 233007.

For more on activity-silent models, see:
Lunqvist, M., Rose, J., Herman, P, Brincat, S.L, Buschman, T.J., and Miller, E.K. (2016) Gamma and beta bursts underlie working memory. Neuron, published online March 17, 2016. View PDF »

Stokes, M., Buschman, T.J., and Miller, E.K. (2017) Dynamic coding for flexible cognitive control. The Wiley Handbook of Cognitive Control, The Wiley Handbook of Cognitive Control, Edited by Tobias Egner, John Wiley & Sons, (Chichester, West Sussex, UK). View PDF

Wasmuht, D. F., Spaak, E., Buschman, T. J., Miller, E. K., & Stokes, M. G. (2017). Intrinsic neuronal dynamics predict distinct functional roles during working memory. bioRxiv, 233171.

Stokes, M. G. (2015). ‘Activity-silent’working memory in prefrontal cortex: a dynamic coding framework. Trends in Cognitive Sciences, 19(7), 394-405.