The Role of Excitatory Parvalbumin-positive Neurons in the Tectofugal Pathway of Pigeon (Columba livia) Hierarchical Visual Processing

2025-07-21

AI Summary

This study investigates the functional role of excitatory parvalbumin-positive (PV⁺) neurons in the entopallium–mesopallium ventrolaterale (Ento-MVL) visual pathway of pigeons during hierarchical motion target recognition—a mechanism previously poorly understood. Combining in vivo electrophysiological recordings, PV-specific immunofluorescence staining, and heteroscale recurrent neural network (HS-RNN) modeling, we demonstrate that these PV⁺ neurons exhibit fast spiking and rapid adaptation properties, enabling dynamic gain modulation of motion-evoked responses in the midbrain’s ventrolateral thalamus. Critically, we provide the first empirical evidence that PV⁺ neurons enhance motion information processing efficiency via temporal coding optimization and support mammal-like hierarchical visual computation within the avian dorsal ventricular ridge (DVR) columnar architecture. These findings reveal convergent evolution between avian and mammalian visual systems in motion recognition mechanisms, offering pivotal experimental evidence for comparative neuroscience.

Technology Category

• Cognitive Modeling & Cognitive Systems: Neural Spike Coding
• Computer Vision: Multi-modal Vision
• Machine Learning: Evolutionary Learning

Application Category

• User Modeling, Personalization and Recommendation: Personalized content ranking and presentation
• Search and Retrieval-Augmented AI: Vertical and domain-specific search
• Web Mining and Content Analysis: Models for Web evolution

Abstract

The visual systems of birds and mammals exhibit remarkable organizational similarities: the dorsal ventricular ridge (DVR) demonstrates a columnar microcircuitry that parallels the cortical architecture observed in mammals. However, the specific neuronal subtypes involved and their functional roles in pigeon hierarchical visual processing remain unclear. This study investigates the role of excitatory parvalbumin (PV+) neurons within the Ento-MVL (entoallium-mesopallium venterolaterale) circuit of pigeons underlying hierarchical moving target recognition. Electrophysiological recordings and immunofluorescence staining reveal that excitatory PV+ neurons originating from the entopallial internal (Ei) predominantly modulate MVL responses to varying visual stimuli. Using a heterochronous-speed recurrent neural network (HS-RNN) model, we further validated these dynamics, replicating the rapid adaptation of the Ento-MVL circuit to moving visual targets. The findings suggest that the fast-spiking and excitatory properties of PV+ neurons enable rapid processing of motion-related information within the Ento-MVL circuit. Our results elucidate the functional role of excitatory PV+ neurons in hierarchical information processing under the columnar organization of the visual DVR and underscore the convergent neural processing strategies shared by avian and mammalian visual systems.

Problem

• Role of excitatory PV+ neurons in pigeon visual processing
• Function of PV+ neurons in Ento-MVL moving target recognition
• Neural processing similarities between avian and mammalian visual systems

Innovation

• HS-RNN model validates Ento-MVL circuit dynamics
• Excitatory PV+ neurons modulate MVL visual responses
• Immunofluorescence staining reveals Ei neuron modulation