Miller Lab – Page 48 – The Miller Lab @ MIT

29

Apr 2013

Ruth Propper responds to “Fist-clenchingly poor science” by Simons

Miller Lab

Neuroscience

The response is here:
http://www.plosone.org/annotation/listThread.action?root=64951

I’ll make one comment::
Propper refers to criticisms of “rigid focus on p values” to justify calling effects “trends” or even “strong trends” when their p values are not significant. Nonsense! Statistics keep us honest. They are objective tests that prevent us from accepting or supporting hypotheses simply because we like that hypothesis. How often do you see authors calling non-significant effects “trends” when they don’t support the author’s conclusion?
29

Apr 2013

Samsung Demos a Tablet Controlled by Your Brain

Miller Lab

Neuroscience

An easy-to-use EEG cap could expand the number of ways to interact with your mobile devices. It reads brainwaves (correlated brain rhythms) using a dry EEG cap.
http://www.technologyreview.com/news/513861/samsung-demos-a-tablet-controlled-by-your-brain/

NY Times Blog: Disruptions: Brain Computer Interfaces Inch Closer to Mainstream
29

Apr 2013

Associative Learning Enhances Population Coding by Inverting Interneuronal Correlation Patterns

Miller Lab

Neuroscience

Jeanne et al. show that changes in correlation between neurons enhances learning. It improves neural discrimination by enhancing noise suppression.
http://www.cell.com/neuron/abstract/S0896-6273(13)00181-5

Preview by Frédéric E. Theunissen, Julie E. Elie:
http://www.cell.com/neuron/abstract/S0896-6273(13)00314-0
28

Apr 2013

Enduring values in academia

Miller Lab

Neuroscience

“Within the walls of the university, the professors come and go as they choose, occasionally teaching, but most often indifferent to the students. Professors with abilities of value to commerce, navigation arts, or in compounding medicinals, seat themselves in the comforts of the university, but devote their time and skill to personal gain. Their rapacity is exceeded only by their hatred for each other and disdain for the citizenry. Upon being called to attend to their established duties, they bitterly complain of intrusions on their freedom. In the universities, it is a woeful situation.”

Gianfredo Capitolano, Rector of Bensilatano University, quoted in 1435. He was killed in 1437 by a deranged doctoral candidate.

(Sorry for the repost. This still makes me chuckle.)
28

Apr 2013

Fist-clenchingly poor science

Miller Lab

Neuroscience

Jon Simons and The Neurocritic tear apart a study claiming to show that unilateral fist clenching can improve memory encoding or recall.

http://www.plosone.org/annotation/listThread.action?root=64951

http://neurocritic.blogspot.dk/2013/04/want-to-remember-something-clenching.html
27

Apr 2013

Visual stimulus eccentricity affects human gamma peak frequency

Miller Lab

Neuroscience, Publications

Van Pelt and Fries show that the peak frequency of gamma-band decreases with stimulus eccentricity and that stationary and moving stimuli are similarly modulated. These results argue that gamma is related to stimulus salience and are consistent with recent observations of increased gamma vs beta synchrony for bottom-up vs top-down attention in the frontoparietal cortical network (Buschman and Miller (2007).
http://www.sciencedirect.com/science/article/pii/S105381191300387X

For further reading:
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 The Scientist’s “Hot Paper” for October 2009. View PDF »
27

Apr 2013

THE PREFRONTAL CORTEX AS A QUINTESSENTIAL “COGNITIVE-TYPE” NEURAL CIRCUIT

Miller Lab

Neuroscience, Publications

In the review, Xiao-Jing Wang deconstructs the cellular and circuit mechanisms involved in sustained “working memory” activity. Among other things, Wang shows that these circuits do not merely latch onto a sensory input, the same circuits are involved in decision-making computations.
http://wang.medicine.yale.edu/pdf_pub/wang.pfc-book-chapter2012.pdf

Related Miller Lab work cited by Wang:
Miller, E.K. and Cohen, J.D. (2001) An integrative theory of prefrontal cortex function. Annual Review of Neuroscience, 24:167-202. Designated a Current Classic by Thomson Scientific as among the most cited papers in Neuroscience and Behavior. View PDF »

Fusi, S., Asaad, W.F., Miller, E.K., and Wang, X.J. (2007) A neural circuit model of flexible sensori-motor mapping: Learning and forgetting on multiple timescales. Neuron. 54: 319-333. View PDF »

Asaad, W.F., Rainer, G. and Miller, E.K. (1998) Neural activity in the primate prefrontal cortex during associative learning. Neuron, 21:1399-1407. View PDF »

Wallis, J.D., Anderson, K.C., and Miller, E.K. (2001) Single neurons in the prefrontal cortex encode abstract rules. Nature, 411:953-956. View PDF »

Miller, E.K., Erickson, C.A., and Desimone, R. (1996) Neural mechanisms of visual working memory in prefrontal cortex of the macaque. Journal of Neuroscience. 16:5154-5167. View PDF »
26

Apr 2013

Representation of Abstract Quantitative Rules Applied to Spatial and Numerical Magnitudes in Primate Prefrontal Cortex

Miller Lab

Neuroscience, Publications, Team Members

In this paper, Miller Lab alumnus Andreas Nieder tested neurons in the prefrontal cortex while animals switched between performing “greater than” vs “less than” rules on either spatial or numerical values. A majority of the engaged neurons were selective for either the spatial or numerical judgments. However, a significant proportion of neurons were “generalists” in the sense that they coded both types magnitude judgments.
Eiselt and Nieder (2013) Journal of Neuroscience

This supports a growing body of evidence that many neurons in higher-level cortex can participate in different functions. Like LIP neurons that categorize both motion and objects (Fitzgerald et al, Nature Neurosciene, 2011), these neurons were cognitive generalists that can participate in different magnitude judgments. We have shown that the proportion of specialists vs generalists neurons in the PFC depends on task demands. If the two category problems are disssimilar (cats vs dog and sport cars vs sedans) and can’t be confused, the majority of PFC neurons were generalists.. If instead, the category problems are similar and can easily be confused (categorizing the same set of animals in two different ways), the modal group of PFC neurons were specialists. It is as if the PFC was orthogonalizing the two potentially confusable categories to reduce errors. This shows that the PFC is highly sensitive to top-down demands, more so than bottom-up information, and can adapt the way it represents information to meet current cognitive demands.

For further reading, see:
Cromer, J.A., Roy, J.E., and Miller, E.K. (2010) Representation of multiple, independent categories in the primate prefrontal cortex. Neuron, 66: 796-807. View PDF »
Roy, J.E., Riesenhuber, M., Poggio, T., and Miller, E.K. (2010) Prefrontal cortex activity during flexible categorization. Journal of Neuroscience, 30:8519-8528. View PDF »
26

Apr 2013

New publication: Limber Neurons for a nimble mind

Miller Lab

Neuroscience

Limber Neurons for a Nimble Mind
Earl K. Miller and Stefano Fusi
Neuron. 78:211-213, 2013. (Preview)
View PDF
25

Apr 2013

Dynamic Coding for Cognitive Control in Prefrontal Cortex

Miller Lab

Neuroscience

For years, researchers have noted that many neurons in the prefontal cortex have “weird” properties. They respond to a wide range of seemingly unrelated unrelated information. These kitchen sink, “mixed selectivity” neurons were often ignored or dismissed because they didn’t seem to make sense (well, except to network modelers who knew about hidden units and support vector machines). Stokes et al recorded from multiple electrodes in the prefrontal cortex. This revealed shifting patterns of PFC activity that followed a trajectory through multi-dimensional space from signaling sensory events to internal factors like rules and decisions. Many PFC neurons participated in multiple states. Thus, mixed selectivity doesn’t result in cortical porridge but rather an orderly progression of mental states, provided you have multiple electrodes and can simultaneously take multiple neurons into account.

Stokes et al. (2013) Neuron, 78: 364-375

Read a Preview of Stokes et al:
Miller, E.K. and Fusi, S. (2013) Limber neurons for a nimble mind. Neuron. 78:211-213. View PDF »