Usamma Amjad

This study shows that dopamine signals in the striatum track slow internal states of behavioral performance, distinct from reward prediction errors, and are organized by task demands.

This paper develops micro-invasive probes for dual chemical and electrical neural activity recording in nonhuman primates, demonstrating long-term functionality over one year.

This paper describes a new neural implant that enables long-term, aseptic recording of both neurochemical and electrophysiological activity in nonhuman primates.

The paper develops a method to simultaneously measure dopamine and neuronal spikes in monkeys using carbon fiber electrodes and validates it for cell-type specific activity related to behavior.