Matthew Nassar, PhD
Postdoctoral fellow

Ph.D., Neuroscience, 2012
University of Pennsylvania | Philadelphia, Pennsylvania


Research Interests


I am interested in how neuromodulators might allow cortical circuitry to facilitate different behavioral regimes in order to allow optimization across a broad array of environmental contexts. For example, one branch of my research investigates the role of catecholamines in adjusting the relative contributions of internal and external sources of information to improve learning and perception in dynamic environments. My research relies on detailed quantification of human behavior in cognitive and perceptual tasks, computational modeling, and indirect measurements of neural function such as fMRI, EEG, and pupillometry.



Publications & Manuscripts


Nassar MR,
Helmers J, Frank MJ. Chunking as a rational strategy for lossy data compression in visual working memory tasks. [under review; available on biorxiv: http://biorxiv.org/content/early/2017/01/06/098939]

*Krishnamurthy K, *Nassar M, Sarode S, Gold J. Adaptive, arousal-related adjustments of perceptual biases optimize perception in a dynamic environment. [in press at Nature Human Behaviour; available on biorxiv: http://biorxiv.org/content/early/2016/10/26/083766 ] (* = equal contribution)

Nassar M, Bruckner R, Eppinger B. What do we GANE with age? Behavioral and brain sciences. [commentary on Mather, M., Clewett, D., Sasaki M., & Harley C.W. (in press) Norepinephrine ignites local hotspots of neuronal excitation: how arousal amplifies selectivity in perception and memory behavioral and brain sciences]

Jepma M, Murphy P, Nassar M, Brown S, van den Maagdenberg A, Koelewijn S, de Vries B, Rangel-Gomez M, Meeter M, Nieuwenhuis S. (2016) Noradrenergic regulation of learning rate in a dynamic environment. PLOS Computational Biology 12(10): e1005171.

Nassar M, Frank, MJ. (2016) Taming the beast: extracting generalizable knowledge from computational models of cognition. Current Opinion in Behavioral Sciences 11:49-54

Nassar M, Bruckner R. Gold J, Li S, Heekeren H, Eppinger B. (2016) Age differences in learning emerge from an insufficient representation of uncertainty in older adults. Nature communications.

Liu D, Zhang Y, Gharavi R, Park H,  Lee J, Siddiqui S, Tellejohan R, Nassar M, Cutler R, Jiang H, Becker K, Mattson M. (2015). The Mitochondrial Uncoupler DNP Triggers Brain Cell mTOR Signaling Network Reprogramming and CREB Pathway Upregulation. Journal of Neurochemistry.

*McGuire J, *Nassar M, Heasly B, Gold J, Kable J.  Functionally dissociable influences on learning rate in a dynamic environment.  Neuron 84, 870-881 (* = equal contribution)

Wilson R, Nassar M, Gold J. (2013) A mixture of Delta-rules approximation to Bayesian inference in change-point problems.  PLOS Computational Biology 9(7): e1003150.

Nassar M, Gold J. (2013) A healthy fear of the unknown: perspectives on the interpretation of parameter fits from computational models in neurosciencePLOS Computational Biology 9(4): e1003015.

Nassar M, Rumsey K, Wilson R, Parikh K, Heasly B, Gold J. (2012) Rational regulation of learning dynamics by pupil-linked arousal systems. Nature Neuroscience 12:1040–1046.

Nassar M
, Wilson R, Heasly B, Gold J. (2010) An approximately Bayesian delta-rule model explains the dynamics of belief updating in a changing environment. Journal of Neuroscience. 30(37): 12366-12378.

Wilson R, Nassar M, Gold J. (2010). Bayesian On-line Learning of the Hazard Rate in Change-Point Problems.  Neural Computation. 22:2452–2476.

Tang S, Arumugam T, Cutler R, Jo D, Magnus T, Chan S, Mughal M, Telljohann R, Nassar M, Ouyang X, Calderan A, Ruzza P, Guiotto A, Mattson M. (2007). Neuroprotective actions of a histidine analogue in models of ischemic stroke.  J neurochem. 101(3):729-36.

Johnson J, Summer W, Cutler R, Martin B, Hyun D, Dixit V, Pearson M, Nassar M, Tellejohan R, Maudsley S, Carson O, John S, Laub D, Mattson M. (2007). Alternate day calorie restriction improves clinical findings and reduces markers of oxidative stress and inflammation in overweight adults with moderate asthma.  Free radic biol med. 42(5):665-74.


*Authors contributed equally and listed alphabetically


 

Contact Information


Address:
              Brown university CLPS department

              190 Thayer Street

              Providence RI, 02906

              

Office:

            153 Metcalf hall


Email: