At every waking moment the human brain absorbs information, selectively filters it, and integrates it into perceptions and memories. When presented with the same world, we can effortlessly engage in many different activities depending on our goals. How does the brain flexibly coordinate these functions? What happens when they break down?

Our lab pursues these fundamental questions using a combination of methods including functional Magnetic Resonance Imaging (fMRI), electroencephalography (EEG), transcranial magnetic stimulation (TMS), and studies of patients with different forms of neurological or psychiatric illness. We combine these methods with a sophisticated computational toolkit, examining the representational, processing, and network characteristics of different brain regions.

Networks and hubs

The brain is made up of different areas that flexibly interact as part of large-scale systems or “networks”. In recent years, we have made enormous advances in understanding how these systems are typically organized in humans. This platform allows us to ask exciting new questions, including: 

  • Are hub regions - which interact with many different networks - special? What functions do they carry out?
  • How do networks vary over time, in different contexts, and across individuals?
  • How do networks break down?
  • How do networks contribute to complex behavior?

Top-down control systems of the human brain

Presented with the same sensory input, we can complete many different processes depending on our goals. "Control" refers to our ability to alter neural processing and behavior depending on these objectives. A number of areas in the frontal and parietal lobes have been implicated in these processes. What differentiates these areas? What control functions are they specialized in? How do they interact? Do these interactions change in different contexts?

Top-down modulation of vision

What do “control” systems control? In this line of work, we ask how our goals change the way we see the world. There is abundant work demonstrating that attention to a visual stimulus changes various aspects of its representation, including the gain, tuning, and reliability of responses. We ask: what systems-level mechanisms lead to these changes? Do these differ across individuals and contexts? Are they linked to different neuromodulators?

Methods development

These exciting questions push us to new advances in methodologies, to tackle brain function more precisely and at a wide range of spatiotemporal scales. Thus, our lab engages in a multitude of efforts to integrate existing methods and develop new methodological and analytical approaches. Recent work has included advances in measuring individual variability, reducing artifacts, and combining TMS and fMRI.