PSL300H1 Lecture Notes - Lecture 21: Thalamus, Special Senses, Nociception
Document Summary
We are usually at least partially conscious of the data: as compared to other senses (blood pressure, heart beat, etc. ) Function: transduce of signals the conversation of physical electrical, through receptor potentials (graded changes in membrane potential, triggers neuron to fire ap, or triggers downstream neurons to fire. Adequate stimulus: the form of energy the receptor is most responsive to: highest affinity to the source of physical energy, ex. Thermoreceptors sense temperature (adequate stimulus), but can also respond to pressure if needed: chemoreceptors, chemicals, molecules, ions, o2, glucose, mechanoreceptors, sound, vibrations, pressure, gravity, thermoreceptors, temperature, photoreceptors, photons (lights) Threshold: the weakest stimulus a single receptor can detect: ex. photoreceptor"s threshold single photon of light, ex. chemoreceptor"s threshold single odorant molecule. Perceptual threshold: the weakest stimulus you can consciously perceive: usually much higher than threshold. Primary sensory neurons either the receptor (neuron) or the first neuron immediately downstream the receptor cell.
