Our mission is two-fold: (i) to understand the typical function and development of
brain systems that mediate core aspects of emotional processing and reactivity and (ii) to apply the basic knowledge obtained from studies of healthy populations to better characterize the dysfunction of neuroaffective processes underlying risk for clinical anxiety and mood disorders.
Much of the research in our lab involves extending and translating what we know about the psychobiological roots of motivation and emotion from non-human animal research to human experimentation.
Our research has been funded by NIMH, NSF, SUNY and Tal-Medical Inc.
A methodological mainstay in our lab is the recording of spontaneous and event-related human cortical electrophysiology. Specifically, we utilize dense-array EEG recordings (see inset below) that permit relatively high spatial sampling of the brain's electric fields. By employing dense electroencephalogram (EEG) recording montages we are able to perform advanced analyses that help to minimize distortion introduced by the spatial smearing of electrical currents and in some cases to estimate the cerebral generators of the signals recorded at the skull surface.
Understanding how behavior, cognition and experience emerge from dynamic cellular and network-level neuronal interactions stands as the grand challenge for systems neuroscience. Considerable evidence suggests that the spatio-temporal coordination of rhythmic neuronal activity at the population level can serve as the bridge between the spiking of single units and integrative function.Recording the field potentials of large-scale neuronal populations can therefore provide us with a window into the dynamics of brain function during different types of affective and cognitive states. Information processing within the brain appears to be organized via the perturbation of ongoing oscillations of neuronal populations at both local and global scales.
Oscillations manifesting across different frequency bands become transiently synchronized to form broadly distributed functional networks within the brain. We are interested in quantifying instances of such long-range functional connectivity in near real-time (in this regard, we have contributed open-source software code, for example, to the Neurophysiological Biomarker Toolbox maintained by the Center for Neurogenomics and Cognitive Research at University Amsterdam).
Another special methodological focus within the lab is on using highly selective paradigms for isolating in-vivo sensory circuit function (e.g., steady-state visual evoked potentials or ssVEPs) and advanced signal processing methods that provide the resolution of event-related brain dynamics at the level of single-trials in contrast to traditional approaches that involve aggregating over hundreds of repetitions of experimental stimuli.
A Causal Role for Brain Dynamics?
The availability of novel, non-invasive techniques for brain stimulation now allows investigators to directly modulate neuronal oscillations in a completely safe manner within the laboratory. We utilize several such approaches for directly targeting and modulating neuronal rhythms.
One method involves pulsed light modulation, delivered at specific frequencies.This form of patterned stimulation effectively entrains neuronal rhythms.
Yet another method involves using transcranial oscillating currents (toDCS), by which we can target specific frequencies of interest and move beyond establishing brain-behavior correlations to performing causal intervention studies.
Currently, we are exploring the effects of targeted toDCS on endogenous and exogenous brain dynamics, in order to address fundamental questions of interest related to emotion, attention and learning. We have also been conducting studies employing simultaneous high-density EEG and low field strength magnetic (LFMS) stimulation.