Prefrontal granular cortex of the rhesus monkey. I. Intrahemispheric cortical afferents

In 6 adolescent rhesus monkeys, unilateral injections of horseradish peroxidase (HRP) were made into 6 regions on the convexity of the prefrontal granular cortex. The afferents to each zone were considered with respect to whether they were local afferents (from adjacent frontal areas) or distal afferents (from outside frontal lobe). The strongest input onto prefrontal granular cortex comes from the temporal lobe and especially areas in and around the superior temporal gyrus. Area 10 in the frontal pole region receives input primarily from area 22 in the superior temporal gyrus and dorsal portion of the superior temporal sulcus. That portion of area 46 above the principal sulcus receives input primarily from area 22 in the upper bank of the superior temporal sulcus while area 46 below the principal sulcus has input from the insula of the superior temporal sulcus and area 21 in the lower bank of the superior temporal sulcus. The cortex within the concavity of the acurate sulcus differs in that the dorsal half (including areas 46 and 8a) receives input primarily from the dorsal bank and to a lesser degree the insula of the superior temporal sulcus while the ventral portion of this region including areas 45 and 46 receives input primarily from the lower bank of the superior temporal sulcus, inferior temporal gyrus and insula of the superior temporal sulcus. Input was noted from cingulate areas 23 and 24 to all 6 injected regions while retrosplenial cortex was noted to project to all but one of the injected regions, i.e. area 10. In addition, some labeled neurons were seen in area 7 after injections into area 46 and some were also seen in the inferior temporal gyrus and parahippocampal region after injections into the arcuate region. Finally, labeled neurons were noted in area 19 after injections into the ventral portion of the prefrontal granular cortex bounded by the arcuate sulcus. The HRP-positive neurons that comprised the intrahemispheric cortical afferents to prefrontal granular cortex were located primarily in layer iii. They were pyramidal in shape and ranged in size from small to medium. These neurons were found to be distributed in a horizontal band in which the number of labeled neurons waxed and waned, or they were distributed in a patchy or clumped manner. The possibility that both patterns of distribution represent a vertical or columnar organization to these afferent neurons is discussed.

[1]  C. Gilbert,et al.  The projections of cells in different layers of the cat's visual cortex , 1975, The Journal of comparative neurology.

[2]  John Q. Trojanowski,et al.  Amygdaloid projections to prefrontal granular cortex in rhesus monkey demonstrated with horseradish peroxidase , 1975, Brain Research.

[3]  J. Lavail,et al.  Retrograde Axonal Transport in the Central Nervous System , 1972, Science.

[4]  D H Hubel,et al.  Autoradiographic demonstration of ocular-dominance columns in the monkey striate cortex by means of transneuronal transport. , 1974, Brain research.

[5]  E. G. Jones,et al.  Lamination and differential distribution of thalamic afferents within the sensory‐motor cortex of the squirrel monkey , 1975, The Journal of comparative neurology.

[6]  D. Pandya,et al.  A cingulo-amygdaloid projection in the rhesus monkey. , 1973, Brain research.

[7]  M. Imbert,et al.  Polysensory and cortico-cortical projections to frontal lobe of squirrel and rhesus monkeys. , 1969, Electroencephalography and clinical neurophysiology.

[8]  A. Walker,et al.  A cytoarchitectural study of the prefrontal area of the macaque monkey , 1940 .

[9]  S. Zeki,et al.  Convergent input from the striate cortex (area 17) to the cortex of the superior temporal sulcus in the rhesus monkey. , 1971, Brain research.

[10]  E. G. Jones,et al.  Commissural and cortico-cortical "columns" in the somatic sensory cortex of primates , 1975, Science.

[11]  J. Trojanowski,et al.  Medial pulvinar afferents to frontal eye fields in rhesus monkey demonstrated by horseradish peroxidase. , 1974, Brain research.

[12]  M. Mishkin,et al.  OCCIPITOTEMPORAL CORTICOCORTICAL CONNECTIONS IN THE RHESUS MONKEY. , 1965, Experimental neurology.

[13]  N Butters,et al.  Behavioral deficits in monkeys after selective lesions within the middle third of sulcus principalis. , 1971, Journal of comparative and physiological psychology.

[14]  H. Künzle.  Alternating afferent zones of high and low axon terminal density within the macaque motor cortex , 1976, Brain Research.

[15]  T. Powell,et al.  The commissural fibre connections of the primary somatic sensory cortex , 1975, Brain Research.

[16]  D. Pandya,et al.  Intra- and interhemispheric projections of the precentral, premotor and arcuate areas in the rhesus monkey. , 1971, Brain research.

[17]  D. Pandya,et al.  Efferent cortico-cortical projections of the prefrontal cortex in the rhesus monkey. , 1971, Brain research.

[18]  E. Jones.  Interrelationships of parieto-temporal and frontal cortex in the rhesus monkey. , 1969, Brain research.

[19]  J. Lund,et al.  The origin of efferent pathways from the primary visual cortex, area 17, of the macaque monkey as shown by retrograde transport of horseradish peroxidase , 1975, The Journal of comparative neurology.

[20]  S. Zeki,et al.  The secondary visual areas of the monkey. , 1969, Brain research.

[21]  D. Pandya,et al.  Cortico-cortical connections in the rhesus monkey. , 1969, Brain research.

[22]  J. Trojanowski,et al.  Corticothalamic neurons and thalamocortical terminal fields: An investigation in rat using horseradish peroxidase and autoradiography , 1975, Brain Research.