Alexander and Brown show how frontal lobe function can be explained by a hierarchical stack of a computational motif based on predictive coding.
Alexander, W. H., & Brown, J. W. (2018). Frontal cortex function as derived from hierarchical predictive coding. Scientific reports, 8(1), 3843.
Dopamine alters the neural oscillations associated with executive functions but leave sensory-related evoked potential unchanged.
Ott, T., Westendorff, S., & Nieder, A. (2018). Dopamine Receptors Influence Internally Generated Oscillations during Rule Processing in Primate Prefrontal Cortex. Journal of cognitive neuroscience, (Early Access), 1-15.
A very nice review of how neuromodulation affects the mechanisms and circuits underlying attention.
Thiele, A., & Bellgrove, M. A. (2018). Neuromodulation of Attention. Neuron, 97(4), 769-785.
Martínez-Vázquez and Gail show different channels of influence in different frequency bands between frontal and parietal cortex.
Martínez-Vázquez, P., & Gail, A. (2018). Directed Interaction Between Monkey Premotor and Posterior Parietal Cortex During Motor-Goal Retrieval from Working Memory. Cerebral Cortex.
Interesting new study from the Moore Lab showing how spatial information is evident in different frequency bands in the prefrontal cortex. They also show a dissociation between high gamma/spiking and alpha.
Chen, X., Zirnsak, M., & Moore, T. (2018). Dissonant Representations of Visual Space in Prefrontal Cortex during Eye Movements. Cell Reports, 22(8), 2039-2052.
From Cortech Solutions.
Personal Highlights of the Plenary Sessions
Earl Miller: Rule+Rhythms=Cognition
Interesting new work from Ito and Cole showing how network connectivity patterns is associated with representational flexibility.
Ito, T., & Cole, M. W. (2018). Network dimensionality underlies flexible representation of cognitive information. bioRxiv, 262626.
Interesting study showing that there are decreases in the frequency of alpha oscillations when a task requires require integration of two inputs that are separated in time. The slowing fosters integration by making it more likely that two stimuli fall within one alpha cycle and are thus integrated. Cool.
Wutz, A., Melcher, D., & Samaha, J. (2018). Frequency modulation of neural oscillations according to visual task demands. Proceedings of the National Academy of Sciences, 201713318.
Lundqvist, M., Herman, P. Warden, M.R., Brincat, S.L., and Miller, E.K. (2018) Gamma and beta bursts during working memory read-out suggest roles in its volitional control. Nature Communications. 9, Article number: 394 doi:10.1038/s41467-017-02791-8
Working memory (WM) activity is not as stationary or sustained as previously thought. There are brief bursts of gamma (~50–120 Hz) and beta (~20–35 Hz) oscillations, the former linked to stimulus information in spiking. We examined these dynamics in relation to readout and control mechanisms of WM. Monkeys held sequences of two objects in WM to match to subsequent sequences. Changes in beta and gamma bursting suggested their distinct roles. In anticipation of having to use an object for the match decision, there was an increase in gamma and spiking information about that object and reduced beta bursting. This readout signal was only seen before relevant test objects, and was related to premotor activity. When the objects were no longer needed, beta increased and gamma decreased together with object spiking information. Deviations from these dynamics predicted behavioral errors. Thus, beta could regulate gamma and the information in WM.
Wutz, A., Loonis, R., Roy, J.E., Donoghue, J.A., and Miller, E.K. (2018) Different levels of category abstraction by different dynamics in different prefrontal areas. Neuron published online Jan 25 2018.
Categories can be grouped by shared sensory attributes (i.e. cats) or by a more abstract rule (i.e. animals). We explored the neural basis of abstraction by recording from multi-electrode arrays in prefrontal cortex (PFC) while monkeys performed a dot-pattern categorization task. Category abstraction was varied by the degree of exemplar distortion from the prototype pattern. Different dynamics in different PFC regions processed different levels of category abstraction. Bottom-up dynamics (stimulus-locked gamma power and spiking) in ventral PFC processed more low-level abstractions whereas top-down dynamics (beta power and beta spike-LFP coherence) in dorsal PFC processed more high-level abstractions. Our results suggest a two-stage, rhythm-based model for abstracting categories.