Fig. 4.

Receptive fields in the newborn's SC shifted systematically as neurons were sampled at progressively more caudal locations. The middle schematic illustrates the path of an electrode on a drawing of a parasagittal section. Each of the symbols represents a sensory-responsive neuron whose receptive field(s) was mapped. Note that, as the electrode advanced, the progression of receptive fields (shading) was from those representing frontal or rostral sensory space to those representing temporal or caudal sensory space. Boxeshighlight the receptive fields of multisensory neurons.Numbers represent the recorded depth of each neuron from the surface of the SC. Conventions are the same as in Figure 3.Sup, Superficial layers; Deep, multisensory layers; PAG, periaqueductal gray;IC, inferior colliculus.