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Figure 4. Afferents to (A and B) and efferents from (C and D) the frontal cortex. (A) The lateral view of the cortico-cortical networks. (a) Parietotemporal cortex contributes to generating body and space perception; (b) The parieto-prefrontal pathway (Where pathway) transfers perceptive information of self-body and surroundings to promote spatial working memory in the PFC; (c) The parieto-premotor pathway (How pathway) contributes to visually-guided movement control by the PMC; (d) The ventral occipito-temporal pathway (What pathway) conveys semantic information, such as those concerning pattern discrimination and the visual identification of objects; (B) The medial view of the cortico-cortical networks. (a) The cingulate-prefrontal pathway is involved in assigning emotional valence to sensory information; (b) The parieto-medial temporal pathway contributes to spatial route navigation, route learning, and long-term spatial memory; (c) The limbic-prefrontal pathway contributes to encoding and retrieving long-term memory; (C) The lateral view of the cortico-cortical and corticofugal projections. Intra-cortical connections exist among the PFC and rostral and caudal PMC. Signals in the PFC proceed to the primary motor cortex (M1) via the rostral and caudal PMC. The rostral PMC has projections to the brainstem. The caudal PMC and M1 have projections to the brainstem and spinal cord. The primary sensory cortex (S1) has projections to the DCN and dorsal horn of the spinal cord. Cortico-brainstem projections also arise from the PPC, PIVC, LIP, and MST; (D) The medial view of the corticofugal projections to the brainstem and spinal cord. The PAG receives projections from the medial and orbital PFC. The CMAr directly and indirectly connects to the PAG and SC via the amygdala. These corticofugal PAG-SC afferents may contribute to emotional behaviors, such as escaping and freezing. PFC: Prefrontal cortex; PMC: premotor cortices; DCN: dorsal column nuclei; PPC: posterior parietal cortex; PIVC: parieto-insular vestibular cortex; LIP: lateral intraparietal area; MST: middle superior temporal visual area; PAG: periaqueductal grey; CMAr: cingulate motor area; SC: superior colliculus; AAC: auditory association cortex; CMAr and CMAc: rostral and caudal regions of the cingulate motor area; FEF: frontal eye field; PMdr and PMdc: rostral and caudal regions of the dorsal premotor areas; PMv: ventral premotor area; pre-SMA: pre-supplementary motor area; MTA: medial temporal cortical areas; SEF: supplementary eye field; SMA: supplementary motor area; PCC: posterior cingulate cortex; RSA: retrosplenial cortex; TPC: temporopolar cortex.