Papers for the month of December 2017

Downey JE, Brane L, Gaunt RA, Tyler-Kabara EC, Boninger ML

"Motor cortical activity changes during neuroprosthetic-controlled object interaction"
Scientific Reports, 7:16947

Mouse over here for a brief summary or click to open article in a new tab.We investigated how motor cortical activity changed in the presence of an object independently of the kinematics that were being generated using intracortical recordings from two people with tetraplegia. After identifying a population-wide increase in neural ring rates that corresponded with the hand being near an object, we developed an online scaling feature in the BCI system that operated without knowledge of the task.

Foldes ST, Weber DJ

"Altered modulation of sensorimotor rhythms with chronic paralysis"
J Neurophysiol, 118:2412-2420

Mouse over here for a brief summary or click to open article in a new tab.Ee compared the modulation of event-related desynchronization (ERD) from magnetoencephalography (MEG) during attempted and imagined grasping performed by participants with cervical SCI and able-bodied controls. The peak and area of ERD were significantly decreased for individuals without volitional muscle activity when they attempted to grasp compared with able-bodied subjects and participants with SCI with some residual EMG activity but differences were observed between groups during motor imagery.

Anzellotti, S

"Beyond Functional Connectivity: Investigating Networks of Multivariate Representations"
Trends in Cognitive Sciences, 0:1-12

Mouse over here for a brief summary or click to open article in a new tab.A review and discussion of the recent emergence of multivariate and nonlinear methods for studying interactions between brain regions. These new developments bring sensitivity to fluctuations in multivariate information, and offer the possibility to ask not only whether brain regions interact, but how they do so.

Knodt A,, Brigidi BD, & Hariri AR

"Heightened connectivity between the ventral striatum and medial prefrontal cortex as a biomarker for stress-related psychopathology: understanding interactive effects of early and more recent stress"
Psychological Medicine, n/a:n/a

Mouse over here for a brief summary or click to open article in a new tab.Higher recent life stress in the context of child trauma is related to increased coupling of corticostriatal circuitry. This connectivity was also related to symptoms of depression.

Pan, Lisa, Cherkassky, Vladimir, McMakin, Dana, Cha,Christine, Nock, Matthew, and Brent, David

"Machine learning of neural representations of suicide and emotion concepts identifies suicidal youth"
Nature Human Behaviour, 1:911-919

Mouse over here for a brief summary or click to open article in a new tab.This study used machine-learning algorithms (Gaussian Naive Bayes) to identify such individuals (17 suicidal ideators versus 17 controls) with high (91%) accuracy, based on their altered functional magnetic resonance imaging neural signatures of death-related and life-related concepts. The most discriminating concepts were ‘death’, ‘cruelty’, ‘trouble’, ‘carefree’, ‘good’ and ‘praise’. A similar classification accurately (94%) discriminated nine suicidal ideators who had made a suicide attempt from eight who had not. This study establishes a biological, neurocognitive basis for altered concept representations in participants with suicidal ideation, which enables highly accurate group membership classification.

Samonds, J.M., Feese, B.D., Lee, T.S.

"Nonuniform surround suppression of visual responses in mouse V1"
The Journal of Neurophysiology, 118:3282-3292

Mouse over here for a brief summary or click to open article in a new tab.Perception of visual scenes requires active integration of both local and global features to successfully segment objects from the background. Although the underlying circuitry and development of perceptual inference is not well understood, converging evidence indicates that asymmetry and diversity in surround modulation are likely fundamental for these computations. We determined that these key features are present in the mouse. Our results support the mouse as a model to explore the neural basis and development of surround modulation as it relates to perceptual inference.

Jeon B.

"The underdog pathway gets a boost"
Nature Neuroscience, 20:1655-1656

Mouse over here for a brief summary or click to open article in a new tab.Critical periods are defined developmental time windows during which neural representations are malleable to sensory experiences. Ocular dominance plasticity in the visual system is a classic example of how neural response properties are updated to reflect input characteristics experienced by the animal in its local environment. In the December 2017 issue of Nature Neuroscience, Sommeijer et al. describe a previously unrecognized role of the thalamus: development of inhibition in the thalamus regulates ocular dominance plasticity, a form of critical-period plasticity regulation previously ascribed solely to the cortex.

Tervo-Clemmens, B., Quach, A., Foran, W., Chung, T., De Bells, D.M., Clark, D.B.

"Neural Correlates of Rewarded Response Inhibition in Youth at Risk for Problematic Alcohol Use"
Frontiers in Behavioral Neuroscience, 11:1-15

Mouse over here for a brief summary or click to open article in a new tab.This project examined fMRI BOLD responses during a rewarded response inhibition task in you at risk for problematic alcohol use. Results suggested trait impulsivity was associated with poorer response inhibition performance (antisaccade) and reduced BOLD activation in the inferior frontal gyrus and frontal eye fields. However, limited support was found to suggest the relationship between impulsivity and response inhibition was moderated by reward.

Behrmann M., Tarr, M., Venkatesh, P., Boring, M., Robinson, A.

"Very high density EEG elucidates spatiotemporal aspects of early visual processing"
Nature Scientific Reports, 7:16248

Mouse over here for a brief summary or click to open article in a new tab.Results in 1990s characterized the spatial Nyquist rate of EEG, showing that for approximate recovery of the scalp EEG signal, an electrode-density of about 1 electrode per approx 3 cm suffices. We discuss why the problem of recovering the underlying brain signal is different, and show using experiments using a high density EEG system and 3 different analyses that increasing the number of electrodes to super Nyquist densities provides improved accuracy for classifying visual stimuli as compared to Nyquist and sub Nyquist densities.

Holliday, W., Gurnsey, K., Sweet, R.

"A putative electrophysiological biomarker of auditory sensory memory encoding is sensitive to pharmacological alterations of excitatory/inhibitory balance in male macaque monkeys"
Journal of Psychiatry and Neuroscience, ePub ahead of print:NA

Mouse over here for a brief summary or click to open article in a new tab.Altered contextual processing of sounds in schizophrenia (SZ) has often been attributed to reduced NMDA receptor function. Focusing on one specific electrophysiological biomarker - repetition suppression - we show that SZ-like alterations can be induced by either enhancing GABA A receptor function or by reducing NMDA receptor function, thus suggesting that the SZ-specific phenotype might arise from excitatory-inhibitory imbalance rather than a specific NMDA receptor deficit.

Jarbo K., Flemming R.

"Sensory uncertainty impacts avoidance during spatial decisions"
Experimental Brain Research, NA:1-9

Mouse over here for a brief summary or click to open article in a new tab.We show how the salience of sensory signals modulates avoidance bias when making spatial perceptual decisions.