Biology subjects

Stasiak, J.

Publications and source records attributed to Stasiak, J..

4 recordsLinked to original sources

bioRxiv2025

Cardiac-sympathetic state predicts action restraint, gated by demonstrated agency

Withholding action until the appropriate moment is a core challenge of motivated behavior. Using beat-to-beat cardiac contractility during an incentivized reaching task, we show that cardiac-sympathetic outflow predicts action restraint. Under high-reward conditions that induce a speed-accuracy tradeoff, reduced contractility at the time of instruction preceded premature responses (false starts). Under high-loss-avoidance conditions, elevated pre-movement contractility predicted slower, more controlled initiation, but only among participants with above-median task success. These findings suggest cardiac-sympathetic engagement does not simply serve mobilization but flexibly supports context-appropriate action regulation, with recruitment for restraint gated by demonstrated agency.

physiology↗

bioRxiv2025

Incentive valence differentially engages open- and closed-loop basal ganglia circuits during movement initiation

Incentives modulate voluntary movement, yet the circuitry channeling these signals into motor output remains unclear. Classical models emphasize a closed-loop circuit (CLC) linking dorsal putamen (PUTd) with motor cortex, but this pathway is anatomically segregated from affective processing regions. Anatomical and clinical evidence point to an alternative: an open-loop circuit (OLC) from ventral putamen (PUTv) that may route affective signals to motor cortex. Here, we conducted two experiments to test whether a functional OLC exists in humans and whether it is differentially engaged by incentive conditions. First, in 7 T resting-state fMRI (multi-echo), PUTv showed robust functional connectivity with both affective and motor regions, including the cingulate motor area (CMA), even after accounting for PUTd variance. This connectivity pattern supports the plausibility of an independent pathway linking affective basal ganglia regions to the motor cortex. Second, in 3 T task fMRI (incentivized reaching), jackpot (high-reward) and robber (high-loss avoidance) incentive conditions produced distinct behavioral and neural signatures. Jackpot produced a speed-accuracy trade-off, with faster movement initiation but more false starts. Neurally, this coincided with engagement (BOLD responses relevant for initiation speed) being reduced in CLC nodes but not in OLC. Robber, in contrast, eliminated engagement in both OLC and CLC nodes, instead recruiting stopping-related regions (e.g., STN), consistent with an avoidance phenomenology. Together, these findings support a versatile architecture for movement initiation that flexibly engages distinct cortico-subcortical circuits depending on incentive phenomenology, and offer a candidate mechanism through which affective salience and valence modulate voluntary movement. Significance StatementAffective signals profoundly influence movement, yet the mechanisms linking motivationally relevant contexts with motor behavior remain unclear. Combining ultra-high field (7 T) connectomics with task-based (3 T) neuroimaging, we provide the first systems-level evidence in humans for such a mechanism: a ventral putamen-centered open-loop circuit (OLC) connecting affective and motor areas, operating alongside the canonical dorsal putamen-centered closed-loop sensorimotor circuit (CLC). Critically, the phenomenological quality of incentive (how it is construed as reward versus threat) rather than magnitude alone, likely determines which circuit dominates during movement initiation. These findings help to explain paradoxical kinesia in Parkinsons disease, where affective contexts can bypass degraded sensorimotor circuits, and establish foundations for context-based therapeutic interventions.

neuroscience↗

bioRxiv2024

Dissociation of putative open loop circuit from ventral putamen to motor cortical areas in humans I: high-resolution connectomics

Human movement is partly organized and executed by cortico-basal ganglia-thalamic closed-loop circuits (CLCs), wherein motor cortical areas both send inputs to and receive feedback from the basal ganglia, particularly the dorsal putamen (PUTd). These networks are compromised in Parkinsons disease (PD) due to neurodegeneration of dopaminergic inputs primarily to PUTd. Yet, fluid movement in PD can sporadically occur, especially when induced by emotionally arousing events. Rabies virus tracing in non-human primates has identified a potential alternative motor pathway, wherein the ventral putamen (PUTv) receives inputs from subcortical limbic areas (such as amygdala nuclei) and sends outputs to motor cortical areas putatively via the nucleus basalis of Meynert (NBM). We hypothesize that this separable open loop circuit (OLC) may exist in humans and explain the preservation of movement after CLC degradation. Here, we provide evidence for the normal human OLC with ultra-high field (7T), multi-echo functional magnetic resonance imaging. We acquired resting-state functional connectivity (FC) scans from 21 healthy adults (avg. age = 29, 12M/9F, all right-handed) and mapped left-hemisphere seed-to-voxel connectivity to assess PUTv FC with putative subcortical nodes and motor cortical areas. We found that putative OLC node (basolateral amygdala, NBM) FC was greater with PUTv (p < 0.05), while CLC subcortical seed (ventrolateral nucleus of thalamus) FC was greater with PUTd (p<0.01). Striatal FC patterns varied across cortical motor areas, with cingulate (p < 0.0001) and supplementary (p < 0.0001) motor areas showing greater FC with PUTv vs. nucleus accumbens. SMA had greater FC with PUTd vs. PUTv (p < 0.0001), while cingulate and primary motor areas showed no significant differences in FC between PUTd and PUTv (p > 0.1). Collectively, these results suggest that PUTv is functionally connected to motor cortical areas and may be integrated into a separable motor OLC with subcortical limbic inputs.

neuroscience↗

bioRxiv2024

Dissociation of novel open loop from ventral putamen to motor areas from classic closed loop in humans II: task-based function

Humans ubiquitously increase the speed of their movements when motivated by incentives (i.e., capturing reward or avoiding loss). The complex interplay between incentivization and motor output is pertinent for unpacking the functional profiles of different circuits that link the basal ganglia with motor cortical areas. Here, we analyzed the functional profile of nodes forming two circuits involving putamen and motor cortical areas: the traditional "closed-loop circuit" (CLC) from sensorimotor dorsal putamen (PUTd) and a putative "open-loop circuit" (OLC) from ventral putamen (PUTv). Establishing differential function between CLC and OLC is particularly relevant for therapeutic approaches to Parkinsons disease, where OLC function is hypothesized to be relatively spared by the disease process. In a large sample fMRI study, 68 healthy controls executed speeded reaches with a joystick under different levels of incentivization to accurately hit precision targets. We dissociated effects of "incentive per se" (i.e., changes in brain activity when an upcoming movement obtains a reward or avoids a loss) from "RT effects" (i.e., brain activity that directly scales with adjustments to movement initiation time). Incentive per se was observed across sites in both CLC and OLC. However, RT effects were primarily in nodes of the OLC and motor sites, consistent with the hypothesized anatomy and function of OLC. Our findings additionally suggest valence might mediate when incentives recruit OLC to more prominent control of motor behavior.

neuroscience↗