1. Explain how ‘on-center’ retinal ganglion cells increase their firing rates as illumination increases, while ‘off-center’ retinal ganglion cells increase their firing rates when illumination decreases in the centers of their receptive fields.
2. All 4 sensory systems we discussed have orderly representations of their stimuli in primary sensory cortex (eg. somatotopy in SI somatosensory cortex). Briefly describe that organization for all four systems (somatic sensation, pain, vision, auditory system). One sentence should be sufficient for each system