RELATION BETWEEN PATTERNS OF INTRINSIC LATERAL CONNECTIVITY, OCULAR DOMINANCE, AND CYTOCHROME OXIDASE-REACTIVE REGIONS IN MACAQUE MONKEY STRIATE CORTEX

To help understand the role of long-range, clustered lateral connectio ns in the superficial layers of macaque striate cortex (area V1), we h ave examined the relationship of the patterns of intrinsic connections to cytochrome oxidase (CD) blobs, interblobs, and ocular dominance (O D) bands, using biocytin based neuroanatomical tracing, CO histochemis try, and optical imaging. Microinjections of biocytin in layer 3 resul ted in an asymmetric field (average anisotropy of 1.8; maximum spread- 3.7 mm) of labeled axon terminal clusters in layers 1-3, with the long er axis of the label spread oriented orthogonal to the rows of blobs a nd imaged OD stripes, parallel to the V1/V2 border. These labeled term inal patches (n = 186) from either blob or interblob injections (n = 2 0) revealed a 71% (132 out of 186) commitment of patches to the same c ompartment as the injection site; 11% (20 out of 186) to the opposite compartment, and 18% (34 out of 186) to borders of blob-interblob comp artments, indicating that the connectivity pattern is not strictly blo b to blob, or interblob to interblob (p < 0.005; chi 2). In injections placed within single OD domains (n = 11), 54% of the resulting labele d terminal patches (43 out of 79) fell into the same (ED territories a s the injection sites, 28% (22 out of 79) into the opposite OD regions , and 18% (14 out of 79) on borders, showing some connectional bias to ward same-eye compartments (p < 0.02; ANOVA). Individual injection cas es, however, varied in the degree (50-100% for GO patterns, 22-100% fo r OD patterns) to which they showed same-compartment connectivity. The se results reveal that while connectivity between similar compartments predominates (e.g., blob to blob, right eye column to right eye colum n), interactions do occur between functionally different regions.