Antipsychotic Drugs Alter Functional Connectivity between the Medial Frontal Cortex, Hippocampus, and Nucleus Accumbens as Measured by H215O PET

Abstract This EEG study investigates the electrophysiological activity underlying processes of stimulus and response selection, and their executive orchestration via long-range functional connectivity under conflict condition, in order to shed more light on how these brain dynamics shape individual behavioral performance. Participants (n = 91) performed a modified flanker task, in which bilateral visual stimulation and a bimanual response pattern were employed to isolate the stimulus and response selection-related lateralized activity. First, we identified conflict-related markers of task-relevant processes; most importantly, the stimulus and response selection were evidenced by contra–ipsilateral differences in visual and motor activity, respectively, and executive control was evidenced by modulations of midfrontal activity. Second, we identified conflict-related functional connectivity between midfrontal and other task-relevant areas. The results showed that interregional phase synchronization in theta band was centered at the midfrontal site, interpreted here as a “hub” of executive communication. Importantly, the theta functional connectivity was more robust under the condition of increased demands for stimulus and response selection, including connectivity between the medial frontal cortex and the lateral frontal and motor areas, as well as cross-frequency theta–alpha coupling between the medial frontal cortex and contralateral visual areas. Third, we showed that individual differences in the measured conflict-related EEG activity, particularly the midfrontal N2, theta power, and global theta connectivity, predict the behavioral efficiency in conflict resolution.

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Sensitization to amphetamine and stress may involve nucleus accumbens and medial frontal cortex

Brain Research ◽

10.1016/0006-8993(79)90999-5 ◽

1979 ◽

Vol 176 (2) ◽

pp. 412-416 ◽

Cited By ~ 43

Author(s):

Alan J. Eichler ◽

Seymour M. Antelman

Keyword(s):

Nucleus Accumbens ◽

Frontal Cortex ◽

Medial Frontal Cortex

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Divergence of rodent and primate medial frontal cortex functional connectivity

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2003181117 ◽

2020 ◽

Vol 117 (35) ◽

pp. 21681-21689 ◽

Cited By ~ 5

Author(s):

David J. Schaeffer ◽

Yuki Hori ◽

Kyle M. Gilbert ◽

Joseph S. Gati ◽

Ravi S. Menon ◽

...

Keyword(s):

Functional Connectivity ◽

Frontal Cortex ◽

Nonhuman Primates ◽

Functional Organization ◽

Brain Connectivity ◽

Medial Frontal Cortex ◽

Preclinical Model ◽

Preclinical Research ◽

Ultra High Field ◽

Dorsolateral Prefrontal

With the medial frontal cortex (MFC) centrally implicated in several major neuropsychiatric disorders, it is critical to understand the extent to which MFC organization is comparable between humans and animals commonly used in preclinical research (namely rodents and nonhuman primates). Although the cytoarchitectonic structure of the rodent MFC has mostly been conserved in humans, it is a long-standing question whether the structural analogies translate to functional analogies. Here, we probed this question using ultra high field fMRI data to compare rat, marmoset, and human MFC functional connectivity. First, we applied hierarchical clustering to intrinsically define the functional boundaries of the MFC in all three species, independent of cytoarchitectonic definitions. Then, we mapped the functional connectivity “fingerprints” of these regions with a number of different brain areas. Because rats do not share cytoarchitectonically defined regions of the lateral frontal cortex (LFC) with primates, the fingerprinting method also afforded the unique ability to compare the rat MFC and marmoset LFC, which have often been suggested to be functional analogs. The results demonstrated remarkably similar intrinsic functional organization of the MFC across the species, but clear differences between rodent and primate MFC whole-brain connectivity. Rat MFC patterns of connectivity showed greatest similarity with premotor regions in the marmoset, rather than dorsolateral prefrontal regions, which are often suggested to be functionally comparable. These results corroborate the viability of the marmoset as a preclinical model of human MFC dysfunction, and suggest divergence of functional connectivity between rats and primates in both the MFC and LFC.

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