Neural activity throughout the cortex is correlated with perceptual decisions, but inactivation studies suggest that only a small number of areas are necessary for these behaviors. Here we used virtual reality combined with optical recording and perturbation methods to show that the number of required cortical areas and their dynamics vary across related tasks with different cognitive computations.

► February 2018: Postdoc Athena Akrami publishes in Nature on Parametric Working Memory and Sensory History

Congratulations to Athena Akrami, whose paper in Nature is now out (link here).

Athena Akrami

In this paper, Athena combined formal algorithmic behavioral analysis, optogenetic inactivations, and electrophysiological recordings in rats to show that Posterior Parietal Cortex (PPC) is specifically involved in the representation and use of prior sensory experience in Parametric Working Memory (PWM) tasks, where rats compare two sequential auditory stimuli, separated by a delay.

Here’s two fantastic pieces, both on Athena’s paper, one a News and Views piece in Nature by Prof. Laura BusseWorking memory freed from the past, and the other in Neuron by Prof. f. Miguel Maravall : Cortical Lifelogging: The Posterior Parietal Cortex as Sensory History Buffer.

► December 2017: Grad student Leenoy Meshulam publishes in Neuron on collective behavior in hippocampus

Congratulations to Leenoy Meshulam, whose paper in Neuron is out (link here).

Leenoy Meshulam

In this paper, Leenoy shows that correlation patterns in CA1 hippocampus only partially arise from place encoding. She utilizes a population-level modeling approach to uncover collective patterns of activity in CA1 neurons that substantially reflect not only position but also their internal network state states.

The Maximum entropy model introduced in the paper generates predictions that set a particualry high standard for the level of agreement and precision between theoretical predictions (by Leenoy) and experimental data (by Jeff Gauthier).

Leenoy’s paper was rated “exceptional” on Faculty of 1000 — you can read the great recommendation written by Prof. Leonard Maler here.

► Summer 2017: Brodylab produces short film on evidence accumulation

Brodylab and friends produced a short film to accompany our recent paper on evidence accumulation in the July 19th issue of Neuron.  The film was directed by PNI graduate student Rolando Massis-Obando (top center) and starred the folks below.  It included animations by Sue Ann Koay and music by Lake Ruth.  You can watch our video here on youtube!




► Aug 2017: grad student Alex Piet’s paper is out in Neural Computation

Alex Piet

Congratulations to graduate student Alex Piet, whose paper in Neural Computation is now out (link here).

In this paper Alex uses two-node attractor network models to  figure out what neural mechanisms could lead to FOF (a rat cortical region) contributing to decision-making as the lab found in Erlich et al. eLife 2015 and Erlich et al. Neuron 2011. Alex’s results point to specific mechanisms in which the FOF contributes “post-categorization” memory, and make some predictions that Alex then confirmed as correct in a post-hoc analysis of the data.