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How do C-fibres carry temperature signals to the nervous system?

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thermoreception in polar bears — Thermoreception Warm-blooded animals, such as polar bears, maintain stable body temperatures and adapt to substantial geographic and seasonal temperature fluctuations. Thermal adaptation is supported by the function of sensory structures called thermoreceptors.

In mammals, both cold and warm thermoreceptors are innervated by C-fibres, which are unmyelinated nerve fibres that conduct discharge activity to the nervous system very slowly.1

While these fibres facilitate the transmission of temperature signals, it is important to note that cold receptors are also predominantly served by thinly myelinated A-fibres, which conduct impulses more rapidly than C-fibres. Additionally, certain C-fibre nociceptors function as polymodal receptors, responding to various types of sensory stimulation, including painful cold or burning sensations.12

Once these signals reach the spinal cord, they are processed by specialized neurons in the dorsal horn that receive convergent input from these peripheral receptors. From there, the information is transmitted to the brainstem or the forebrain via the lateral spinothalamic tract, eventually reaching the thalamus and the cerebral cortex to produce temperature sensations.3