Figure 4.
Hierarchical connections of auditory cortical areas according to laminar origins of projections. Auditory areas are ordered from lowest to highest, with AI and AAF at the base and areas 35 and 36 at the top. Connectional strength, line thickness: strong (thick), medium (bold), and weak (thin). When connectional strengths are non-reciprocal, mean strength is indicated. Laminar origins, the line origins on the areal boxes: supragranular (top), bilaminar (side), infragranular (bottom). Areas can also be classified by putative functional relations: dorsal areas (yellow background) may represent auditory space, ventral areas (dusky rose background) may specialize in spectral analysis.