A statistical theory of neural memory traces

by Alberto Bernacchia (Department of Neurobiology Yale University, New Haven, CT (USA))

Tuesday 31 May 2011, 15:00 → 17:00 Europe/Rome

Aula Rasetti (Dip. di Fisica - Edificio G. Marconi)

We study the neural mechanisms of memory traces in macaque monkeys. We analyze the responses of single cortical neurons to the animal's performance during a competitive game. We show that modulation of neural activity is consistent with a damped oscillator model, suggesting that neurons are low-dimensional systems. However, relaxation times follow a Frechet distribution across neurons, raising the possibility that we observe the slowest decaying mode of a high-dimensional system near a critical point. Furthermore, the Laplace distribution of amplitudes is consistent with a unitary symmetry, which would stabilize the system's modes. Our findings suggest that neurons have long and robust relaxation times, which may be useful for temporally integrating the events occurring during performance of the task.