HVC (avian brain region)

Overview

The HVC (proper name) is a distinct region of the avian brain that plays a crucial role in the control of song production in songbirds. It is part of the song control system, which is a network of brain nuclei that are involved in the learning and production of song. The HVC is located in the nidopallium, a region of the avian brain that is analogous to the cerebral cortex in mammals.

Diagram of the avian brain highlighting the HVC region

Structure

The HVC is a small, densely packed nucleus that contains several types of neurons. These include projection neurons that connect to other parts of the song system, such as the robust nucleus of the arcopallium (RA) and the Area X. The HVC also contains interneurons that are involved in local processing within the nucleus.

Function

The primary function of the HVC is to generate the motor commands necessary for song production. It is involved in both the learning and execution of song patterns. During song learning, the HVC receives auditory feedback and helps to match the bird's vocal output to a memorized template of the song. In adult birds, the HVC is responsible for the precise timing and sequencing of song syllables.

Development

The development of the HVC is influenced by both genetic and environmental factors. During the critical period of song learning, the HVC undergoes significant changes in size and connectivity. This plasticity is essential for the bird to learn and refine its song. Hormones such as testosterone also play a role in the development and maintenance of the HVC.

Plasticity

The HVC exhibits a remarkable degree of plasticity, particularly during the song learning phase. Neuronal turnover and synaptic remodeling are common in the HVC, allowing for the adaptation and refinement of song patterns. This plasticity decreases as the bird matures, but some degree of flexibility is retained throughout the bird's life.

Related pages

• Songbird
• Neuroplasticity
• Nidopallium
• Robust nucleus of the arcopallium
• Area X