The highlighted structure is the dorsal root ganglion, which the cell bodies in the DRG process signals and transmit them along the proximal processes into the spinal cord.
The dorsal root ganglion (DRG) is a cluster of neurons located in the dorsal root of a spinal nerve and is a component of the peripheral nervous system (PNS) and plays a crucial role in transmitting sensory information from the body to the central nervous system (CNS).
The primary function of the DRG is to relay sensory information from the periphery to the CNS. Sensory receptors in the body detect various stimuli, such as touch, pain, temperature, and proprioception (body position and movement). These stimuli trigger signals that travel along the distal processes of the DRG neurons.