Churchland lab

Temidayo Orederu reports on stress and reversal learning

I attended two interesting posters at tonight’s SFN Diversity Poster Session. Temidayo Orederu, a Hunter college student working Liz Phelp’s lab at NYU, explored the effect of stress on learning. Temidayo is particularly interested in “Reversal learning”: the ability to unlearn an association which once was positive but now is aversive. She brought a large cohort of human subjects into the lab, and examined how a stressful situation affected their reversal learning. She found the the stressed-out subjects were able to learn that a once-positive stimulus was now negative, but NOT that a once-negative stimulus was now positive. This dissociation was surprising and suggests that the two aspects of reversal learning might be mediated by separate circuits, one of which is susceptible to stress. The lesson? Stay calm if you want to learn new contingencies about the world.

Nancy Padilla dissects neural circuits for anxiety, and her PI Josh Gordon

In another poster, Nancy Padilla explored the neural mechanisms underlying anxiety. She works in Josh Gordon’s lab at Columbia University. Nancy expressed Archaerhodopsin in the axon terminals of vental hippocampal neurons that project to the medial prefrontal cortex. She then examined the behavior of mice in an elevated plus maze with and without optical stimulation that causes the Arch to suppress activity in the terminals. She saw a clear behavioral effect: Animals spent much more time in the open arms of the maze during stimulation, suggesting that activating the hippocampal inputs reduced anxiety, encouraging animals to explore. Seeing a clear behavioral effect from this stimulation is exciting and suggests that the hippocampal inputs play an important role in anxiety.