Fig. 4. Extracellular recordings of neurons in antenna of crayfish in response to nocigenic chemical stimuli.

(A,B) Capsaicin. (C,D) Isothiocyanate. Each row shows recordings from one individual. (1, left column) control with no chemicals showing spontaneous baseline activity; (2, center column) control with ethanol only; (3, right column): test with 10 mmol l⁻¹ capsaicin (A,B) or 10 mmol l⁻¹ isothiocyanate (C,D) in ethanol.