Biology subjects

Grasso, S.

Publications and source records attributed to Grasso, S..

4 recordsLinked to original sources

bioRxiv2026

JOINT ACTION AWARENESS IN MACAQUES DURING A MULTIPLAYER VIDEO-GAME CONTEXT

In behavioral neuroscience, research in nonhuman primates often relies on video game like paradigms, including studies of social interaction and joint action. In social studies, establishing whether animals monitor their partner and are aware of their reciprocal interactions in these abstract laboratory settings is essential for interpreting the processes underlying cooperative performance. Here, we examined spontaneous head orienting behavior in two macaques performing a cooperative visuomotor task under highly controlled conditions. The animals sat side by side with their heads unrestrained and used isometric joysticks to control their respective cursors displayed on a shared screen. Depending on trial instructions, they performed either individual actions (SOLO action, SA) or joint actions (JA) to obtain a reward. We quantified spontaneous head rotations toward the partner as an ethologically relevant behavioral indicator of social monitoring. Partner directed head turns occurred more frequently during JA than during SA trials. Crucially, their rate increased with the number of errors made by the partner during JA trials. Together, these findings indicate that macaques monitor their partner during abstract, computer-mediated cooperative interactions and that this monitoring is driven by the performance of the partner. Such spontaneous, context specific orienting toward the partner supports the interpretation that macaques are aware of their dyadic engagement, even in video game like settings. Our results therefore highlight the suitability of controlled visuomotor paradigms for investigating the cognitive-motor processes underlying joint action in nonhuman primates.

neuroscience↗

bioRxiv2025

COSTS AND BENEFITS OF ACTING TOGETHER: A NON-HUMAN PRIMATE MODEL OF COOPERATIVE DECISION-MAKING

Cooperation is a crucial aspect of social behavior, allowing individuals to achieve goals unattainable alone. However, collective actions require costly inter-individual coordination, making continuous cost-benefit evaluation essential before engaging in cooperation. Non-human primate models can help uncover the evolutionary foundations of human cooperation and its underlying neural mechanisms. To this aim, we developed a novel paradigm to analyze the dyadic behavior of two macaques, who took turns in choosing between individual and cooperative actions to obtain variable rewards. Each monkey used a joystick to guide a cursor toward one of two targets, each indicating both the reward magnitude and the action type (i.e. solo action or joint action) required to obtain their payoff. We first observed a linear improvement in dyadic performance with the expected reward magnitude. Although macaques tended to prefer individual actions, they selected to act jointly under favorable payoff conditions, indicating that voluntary cooperation in macaques can emerge as a reward-driven process. Logistic models of their choices revealed the subjective cost monkeys assigned to cooperation, which was consistent across subjects. Nonetheless, the gain rate across different sessions increased over time, suggesting that macaques possess the cognitive ability to optimize their dyadic strategies, by estimating not only the coordination costs but also the benefits of cooperation. We observed a progressive reduction in the subjective cost assigned to joint action, which was not directly dependent on performance improvements. Our findings suggest that non-human primates can weigh the costs and benefits of cooperation, highlighting their ability to dynamically adjust social strategies based on reward contingencies. HIGHLIGHTS- Expected reward magnitude enhances cooperative performance in macaques - Monkeys evaluate the cost-benefit trade-off of cooperative actions in social contexts - In macaques, the subjective cost of cooperation decreases over time, promoting a gradual shift toward a pro-social strategy that maximizes outcomes - Cooperative behavior in macaques can emerge as a reward-driven, cost-benefit decision process - Macaques may exhibit metacognitive dynamics, using internal evaluations of expected outcomes to guide collective behavior

neuroscience↗

bioRxiv2023

A cortical mechanism linking saliency detection and motor reactivity in rhesus monkeys

Sudden and surprising sensory events trigger neural processes that swiftly adjust behavior. To study the phylogenesis and the mechanism of this phenomenon, we trained two rhesus monkeys to keep a cursor inside a visual target by exerting force on an isometric joystick. We examined the effect of surprising auditory stimuli on exerted force, scalp electroencephalographic (EEG) activity, and local field potentials (LFP) recorded from the dorso-lateral prefrontal cortex. Auditory stimuli elicited (1) a biphasic modulation of isometric force: a transient decrease followed by a corrective tonic increase, and (2) EEG and LFP deflections dominated by two large negative-positive waves (N70 and P130). The EEG potential was maximal at the scalp vertex, in all respects similar to the human vertex potential. Electrocortical potentials and force were tightly coupled: the P130 amplitude predicted the magnitude of the corrective force increase, particularly in the EEG electrodes contralateral to the limb exerting force, and in the LFP recorded from deep rather than superficial cortical layers, suggesting a direct effect of the vertex potential on the motor output determining the behavior. These results disclose a phylogenetically-preserved cortico-motor mechanism supporting adaptive behavior in response to salient sensory events.

neuroscience↗

bioRxiv2022

Signal peptide efficiency: from high-throughput data to prediction and explanation

The passage of proteins across biological membranes via the general secretory (Sec) pathway is a universally conserved process with critical functions in cell physiology and important industrial applications. Proteins are directed into the Sec pathway by a signal peptide at their N-terminus. Estimating the impact of physicochemical signal peptide features on protein secretion levels has not been achieved so far, partially due to the extreme sequence variability of signal peptides. To elucidate relevant features of the signal peptide sequence that influence secretion efficiency, an evaluation of ~12,000 different designed signal peptides was performed using a novel miniaturized high-throughput assay. The results were used to train a machine learning model, and a post-hoc explanation of the model is provided. By describing each signal peptide with a selection of 156 physicochemical features, it is now possible to both quantify feature importance and predict the protein secretion levels directed by each signal peptide. Our analyses allow the detection and explanation of the relevant signal peptide features influencing the efficiency of protein secretion, generating a versatile tool for the in silico evaluation of signal peptides.

synthetic biology↗