Fig. 4.

The receptive fields of multisensory neurons decline substantially in size during development. a, Receptive field size (as a percentage of the mean adult value) is plotted as a function of postnatal age. Note the rapid decline for each modality-specific receptive field during the first 4–6 weeks.b, Representative receptive fields (shading) of visual–auditory neurons at three ages (22, 42, and 135 dpn) are plotted onto representations of visual and auditory space. Frontal auditory space is represented on the central hemisphere, and caudal space is represented by a hemisphere that has been split and both halves have been folded forward. Eachconcentric circle represents 10°. c, Representative receptive fields of auditory–somatosensory neurons at three ages (20, 42, and 115 dpn). An arrow points to the small somatosensory receptive field at 115 dpn. d, Representative receptive fields of visual–somatosensory neurons at three ages (20, 42, and 135 dpn). An arrow points to the small somatosensory receptive field at 135 dpn. n, Nasal; T, temporal; S, superior;I, inferior.