Background/Objectives: The vibrotactile system, which is essential for guiding behavior in nocturnal rodents such as mice and rats, provides critical sensory input. To investigate the role of vibrotactile sensory inflow in neonatal locomotion, we used previsual rat pups that underwent bilateral vibrissectomy. Subsequently, their motor behavior was evaluated in an open field test. Methods: A total of 42 previsual pups from four litters were assigned to either bilateral vibrissectomy or sham surgery groups on postnatal days (PND) 9–12, with group allocation balanced across litters. Results: Open-field testing on PND 13 revealed that while vibrissectomy (VE) did not affect gross locomotor activity—such as distance traveled, speed, acceleration, or freezing episodes (all >0.05)—it significantly altered spatial behavior. To quantify spatial patterns of curvy tracks, we analyzed trajectorial compaction within the central zone, lacking the tactile guidance of the walls: trajectories were smoothed using virtual coatings scaled to the vibrissal length (16 mm). For each track, an individual linearized reference path was generated and subjected to identical smoothing. The compaction ratio—calculated as the coated area of the smoothed linearized reference divided by the coated area of the experimental track—was significantly greater in VE pups than in sham controls (p = 0.03). This effect was not attributable to differences in the path length traveled within the central zone. The increased compaction persisted when the smoothing scale was increased 2–3 fold (32–64 mm radii, approximating the pups’ mean body size), but not at smaller scales (2–4 mm). Conclusions: These results demonstrate that tactile input specifically modulates the spatial, rather than locomotor, components of nonvisual navigation. Consequently, the track compaction may serve as a sensitive marker for assessing vibrotactile function in developing laboratory rodents.

The vibrotactile system provides essential sensory input for early behavior in previsual rat pups. To examine its role in spatial navigation, we conducted bilateral vibrissectomy or sham procedures on postnatal day (PND) 9–12 in 42 previsual pups (4 litters, balanced groups). Open-field testing on PND 13 showed that while vibrissectomy (VE) did not alter gross locomotor parameters (distance traveled, speed, acceleration, or freezing episodes; all p > 0.05), it significantly modified spatial behavior. VE pups explored a smaller percentage of the arena area (p = 0.01). We analyzed trajectorial compaction in the central zone (lacking wall tactile support) by smoothing trajectories with virtual coatings scaled to vibrissal length (16 mm). Individual references were generated for each track through linearization and identical smoothing. The compaction ratio, calculated as the ratio between the coated areas of linearized reference and experimental tracks, was significantly higher VE pups compared to sham controls (p = 0.03). No significant group difference was observed in path lengths within the central zone. This effect persisted when smoothing scales increased 2–3 fold (32–64 mm radii, approximating body size), but not at smaller scales (2–4 mm). These findings indicate that vibrissal input regulates spatial rather than locomotor components of previsual behavior. The simple open-field measures (area coverage, track compaction) thus serve as sensitive biomarkers for assessing vibrissal function in developing rodents. This study underscores the organizational role of tactile inputs in early spatial navigation and establishes a translatable hallmark for investigating sensory-guided behavior in neurodevelopment.

The rodent somatosensory system, due to its strict somatotopic organization, is a classic and widely used model for studying the influence of sensory experience on brain development and animal behavior. This review is aimed to systematize data on the early behavioral consequences of postnatal vibrissectomy, analyze the limitations of this model, and propose new approaches to overcoming them. The anatomy and ontogeny of the vibrotactile system in laboratory rodents, sensory deprivation and its effects on vibrissal functions, as well as the translational potential of the model are considered. Vibrissa trimming (cutting whiskers), unlike invasive interventions, does not disrupt the structural integrity of the analyzer but selectively restricts the inflow of species-specific sensory information, thereby allowing the investigation of experience-dependent plasticity of the nervous system. The effect of transient vibrissectomy depends on the timing of its application during postnatal ontogeny. Prospects for further development of this model imply (1) a targeted study of deprivation effects on complex forms of learning, decision-making, and the formation of adaptive behavioral strategies; (2) standardization of experimental protocols to minimize stress caused by manipulations and rigid control of social context influences; and (3) the development and implementation of behavioral paradigms for assessing task outcomes, movement kinematics, action sequences, and emerging strategies. The development of various, time-specific, pathogenetically substantiated models of sensory deprivation-based neurological disorders is necessary for the development of corrective therapies aimed at reducing the risks of negative manifestations of childhood neuropsychiatric deficits in adulthood.