Web site: http://knightlab.berkeley.edu
Research areas: Systems and Computational Neuroscience
The laboratory studies the contribution of subregions of prefrontal cortex to control of cognitive and social behavior in humans. We use electrophysiological, MRI and behavioral techniques to study controls and neurological patients with frontal lobe damage in an effort to understand the neural mechanisms subserving cognitive processing in humans. The laboratory also records the electrocorticogram from neurosurgical patients with implanted electrodes to study network properties supporting behavior in humans in signals recorded directly from the human neocortex.
The Knight laboratory studies the role of prefrontal cortex in human behavior. Human evolution is paralleled by a massive increase in the connectivity of the frontal cortex to other brain regions crucial for the development of human cognitive and social behavior. Damage to prefrontal cortex in humans from neurological or developmental disorders results in profound alterations in the ability to think, plan and interact in a socially appropriate manner. The laboratory is interested in the neural mechanisms by which frontal cortex controls distributed neuronal ensembles in other brain regions critical for both cognitive and social behavior. To achieve these aims the laboratory employs neuropsychological, neuroanatomical, electrophysiological and fMRI techniques to study the physiology of prefrontal function in normal subjects and in neurological patients. The laboratory also records the electrocorticogram (ECoG) from neurosurgical patients with either during acute surgical procedures or in epileptic patients with subdural electrodes implanted for an extended period. This line of research aims to understand the network properties and neural coding supporting behavior in humans. The laboratory is also investigating whether ECoG signals can be used for the development of brain-machine interfaces for use with paralyzed patients. Some broad areas under current investigation in include: What is the timing and neural coding of interactions between prefrontal cortex and other brain regions engaged during attention and memory performance? How does the aging process alter prefrontal function? How do subregions of prefrontal cortex contribute to human behavior? What is the role of ultra-high cortical gamma oscillations and distributed network coherence in huam behavior? Can ultra high gamma oscillations recorded from the human cortex be used to control robotic devices for paralyzed patients?
Knight, R.T. Contribution of human hippocampal region to novelty detection. Nature 383: 256-259, 1996.
Barcelo, P., Suwazono, S. and Knight, R.T. Prefrontal modulation of visual processing in humans. Nature Neuroscience. 3(4): 399-403, 2000.
Gehring, W.J. and Knight, R.T. Prefrontal - cingulate interactions in action monitoring. Nature Neuroscience. 3(5): 516-520, 2000.
Yonelinas, A.P., Kroll, N.E.A., Quamme, J.R., Lazzara, M.M., Sauve, M.J., Widaman, K.F. and Knight, R.T. Effects of extensive temporal lobe damage or mild hypoxia on recollection and familiarity. Nature Neuroscience 5(11): 1236-1241, 2002.
Muller, N.G., Machado, L. and Knight, R.T. Contribution of subregions of the prefrontal cortex to working memory: Evidence from brain lesions in humans. Journal of Cognitive Neuroscience 14(5): 673-686, 2002.
Simon-Thomas, E., Brodsky, K., Willing, C., Sinha, R. and Knight, R.T. Distributed neural activity during object, spatial and integrated processing in humans. Cognitive Brain Research 16: 457-467, 2003.
Beer, J.S., Heerey, E.A., Keltner, D., Scabini, D. and Knight, R.T. The regulatory function of self-conscious emotion: insights from patients with orbitofrontal damage. Journal of Personality and Social Psychology 8594: 594-604, 2003.
Yago, E., Duarte, A., Wong, T. Barcel, F. and Knight, R.T. Temporal kinetics of prefrontal modulation of visual attention. Cognitive, Affective and Behavioral Neuroscience 4: 609-617, 2004.
Kramer, M.A., Edwards, E., Soltani, M., Berger, M.S., Knight, R.T. and Szeri, A.J. Synchronization measures of bursting data: application to the electrocorticogram of an auditory event-related experiment. Physical Review E. 70(1): 011914-1-10, 2004.
Yamaguchi, S., Hale, L., D’Esposito, M. and Knight, R.T. Rapid prefrontal-hippocampal habituation to novel events. Journal of Neuroscience 24(23): 5356-5363, 2004.
Gazzaley, A., Cooney, J.W., McEvoy, K., Knight, R.T. and D’Esposito, M. Top-down enhancement and suppression of the magnitude and speed of neural activity. Journal of Cognitive Neuroscience 17:3: 507-517, 2005.
Simon-Thomas, E.R., Role, K.O. and Knight, R.T. Behavioral and electrophysiological evidence of a right hemisphere bias for the influence of negative emotion on higher cognition. Journal of Cognitive Neuroscience 17:3: 518-529, 2005.
Duarte, A.L., Ranganath, C. and Knight, R.T. Effects of unilateral prefrontal lesions on familiarity, recollection and source memory. Journal of Neuroscience 25(36): 8333-8337, 2005.
Edwards, E., Soltani, M., Deouell, L., Berger, M.S. and Knight, R.T. High gamma activity in response to deviant auditory stimuli recorded directly from human cortex. Journal of Neurophysiology 94(6): 4269-4280, 2005.
Beer, J.S, John, O.P., Scabini, D. and Knight, R.T. Orbitofrontal cortex and social behavior: integrating self-monitoring and emotion-cognition interactions. Journal of Cognitive Neuroscience, 18(6): 871-879, 2006.
Padilla, M.L., Woods, R.A., Hale, L.A. and Knight, R.T. Lapses in a prefrontal-extrastriate preparatory attention network predicts mistakes. Journal of Cognitive Neuroscience, 18(9): 1477-1487, 2006.
Canolty, R., Edwards, E., Soltani, M., Dalal, S.S., Kirsch, H.E., Barbaro, N.M., Berger, M.S. and Knight, R.T. High gamma power is phase-locked to theta oscillations in human neocortex. Science, 313: 1626-1628, 2006.