Rober Boshra

The primate pulvinar has been implicated in coordinating cortical networks during attention, but its causal role remains elusive. Like other thalamic nuclei, pulvinar neurons switch between tonic and burst firing, but whether bursts influence behavior and cognitive processes is unknown. Here, we show that pulvinar bursts are not only modulated by attention but also predict behavioral performance. In macaques performing a covert attention task, bursts were more frequent for non-cued targets and uniquely reconfigured population codes in parietal cortex. Crucially, electrical microstimulation of pulvinar triggered bursts that enhanced target detection and synchronized cortical spiking, with behavioral benefits scaling with the strength of burst recruitment. These results establish pulvinar bursts as a causal driver of attention, revealing a thalamo-cortical mechanism by which thalamus exerts moment-to-moment control over cortical processing and behavior.

The Journal of Neuroscience launched an open peer review (OPR) initiative in late 2023 to enhance transparency and accountability in scientific publishing. Analysis of 740 manuscripts and 1,490 reviews revealed that 81.4% of authors opted to share rebuttal letters, with increasing participation over time (67.6% in Dec 2023 to 94.4% in Aug 2024). Reviewer participation was lower (66.8%) but stable, with higher opt-in rates for longer, higher-quality reviews. Geographical analysis of author and reviewer institutions showed that authors from North American and European institutions had greater OPR opt-in rates, authors from Asian institutions had lower opt-in rates, and reviewers from North American institutions had lower opt-in rates compared with the average rates across regions. Further, analysis of manuscript subdiscipline showed it to be predictive of OPR opt-in rates, e.g., authors of manuscripts in cellular or molecular neuroscience were less likely to opt-in compared with the average across subdisciplines. Overall, OPR acceptance is growing, reflecting a positive shift toward open science.

Background/Objectives: Coma prognosis is challenging, as patient presentation can be misleading or uninformative when using behavioral assessments only. Event-related potentials have been shown to provide valuable information about a patient’s chance of survival and emergence from coma. Our prior work revealed that the mismatch negativity (MMN) in particular waxes and wanes across 24 h in some coma patients. This “cycling” aspect of the presence/absence of neurophysiological responses may require fine-grained tools to increase the chances of detecting levels of neural processing in coma. This study implements multivariate pattern analysis (MVPA) to automatically quantify patterns of neural discrimination between duration deviant and standard tones over time at the single-subject level in seventeen healthy controls and in three comatose patients. Methods: One EEG recording, containing up to five blocks of an auditory oddball paradigm, was performed in controls over a 12 h period. For patients, two EEG sessions were conducted 3 days apart for up to 24 h, denoted as day 0 and day 3, respectively. MVPA was performed using a support-vector machine classifier. Results: Healthy controls exhibited reliable discrimination or classification performance during the latency intervals associated with MMN and P3a components. Two patients showed some intervals with significant discrimination around the second half of day 0, and all had significant results on day 3. Conclusions: These findings suggest that decoding analyses can accurately classify neural responses at a single-subject level in healthy controls and provide evidence of small but significant changes in auditory discrimination over time in coma patients. Further research is needed to confirm whether this approach represents an improved technology for assessing cognitive processing in coma.

Close examination of structural MRI in eight nonhuman primates following craniotomy surgeries for intracranial electrophysiology highlights a prevalence of hyperintensities on T2-weighted scans following surgeries conducted using electric and piezoelectric drills, but not when using mechanical, hand-operated drills. We interpret these anomalies as edema of neural tissue that resolved 2–3 wk postsurgery. This finding is especially of interest as electrophysiological recordings from compromised tissue may directly influence the integrity of collected data immediately following surgery.

In-vivo electrophysiology requires direct access to brain tissue, necessitating the development and refinement of surgical procedures and techniques that promote the health and well-being of the animal subjects. Here, we report a series of findings noted on structural magnetic resonance imaging (MRI) scans in monkeys with MRI-compatible implants following small craniotomies that provide access for intracranial electrophysiology. We found distinct brain regions exhibiting hyperintensities in T2-weighted scans that were prominent underneath the sites at which craniotomies had been performed. We interpreted these hyperintensities as edema of the neural tissue and found that they were predominantly present following electric drilling, but not when manual, hand-operated drills were used. Further, the anomalies subsided within 2-3 weeks following surgery. Our report highlights the utility of MRI-compatible implants that promote clinical examination of the animal’s brain, sometimes revealing findings that may go unnoticed when incompatible implants are used. We show replicable differences in outcome when using electric vs. mechanical devices, both ubiquitous in the field. If electric drills are used, our report cautions electrophysiological recordings from tissue directly underneath the craniotomy for the first 2-3 weeks following the procedure due to putative edema.

Cognitive control guides behaviour by controlling what, when, and how information is represented in the brain1. For example, attention controls sensory processing; top-down signals from prefrontal and parietal cortex strengthen the representation of task-relevant stimuli2-4. A similar 'selection' mechanism is thought to control the representations held 'in mind'-in working memory5-10. Here we show that shared neural mechanisms underlie the selection of items from working memory and attention to sensory stimuli. We trained rhesus monkeys to switch between two tasks, either selecting one item from a set of items held in working memory or attending to one stimulus from a set of visual stimuli. Neural recordings showed that similar representations in prefrontal cortex encoded the control of both selection and attention, suggesting that prefrontal cortex acts as a domain-general controller. By contrast, both attention and selection were represented independently in parietal and visual cortex. Both selection and attention facilitated behaviour by enhancing and transforming the representation of the selected memory or attended stimulus. Specifically, during the selection task, memory items were initially represented in independent subspaces of neural activity in prefrontal cortex. Selecting an item caused its representation to transform from its own subspace to a new subspace used to guide behaviour. A similar transformation occurred for attention. Our results suggest that prefrontal cortex controls cognition by dynamically transforming representations to control what and when cognitive computations are engaged.

A consistent limitation when designing event-related potential paradigms and interpreting results is a lack of consideration of the multivariate factors that affect their elicitation and detection in behaviorally unresponsive individuals. This paper provides a retrospective commentary on three factors that influence the presence and morphology of long-latency event-related potentials—the P3b and N400. We analyze event-related potentials derived from electroencephalographic (EEG) data collected from small groups of healthy youth and healthy elderly to illustrate the effect of paradigm strength and subject age; we analyze ERPs collected from an individual with severe traumatic brain injury to illustrate the effect of stimulus presentation speed. Based on these critical factors, we support that: (1) the strongest paradigms should be used to elicit event-related potentials in unresponsive populations; (2) interpretation of event-related potential results should account for participant age; and (3) speed of stimulus presentation should be slower in unresponsive individuals. The application of these practices when eliciting and recording event-related potentials in unresponsive individuals will help to minimize result interpretation ambiguity, increase confidence in conclusions, and advance the understanding of the relationship between long-latency event-related potentials and states of consciousness.