Forebrain connectivity of the prefrontal cortex in the marmoset monkey (Callithrix jacchus): An anterograde and retrograde tract‐tracing study

Abstract

The cortical and subcortical forebrain connections of the marmoset prefrontal cortex (PFC) were examined by injecting the retrograde tracer, choleratoxin, and the anterograde tracer, biotin dextran amine, into four sites within the PFC. Two of the sites, the lateral and orbital regions, had previously been shown to provide functionally dissociable contributions to distinct forms of behavioral flexibility, attentional set-shifting and discrimination reversal learning, respectively. The dysgranular and agranular regions lying on the orbital and medial surfaces of the frontal lobes were most closely connected with limbic structures including cingulate cortex, amygdala, parahippocampal cortex, subiculum, hippocampus, hypothalamus, medial caudate nucleus, and nucleus accumbens as well as the magnocellular division of the mediodorsal nucleus of the thalamus and midline thalamic nuclei, consistent with findings in the rhesus monkey. In contrast, the granular region on the dorsal surface closely resembled area 8Ad in macaques and had connections restricted to posterior parietal cortex primarily associated with visuospatial functions. However, it also had connections with limbic cortex, including retrosplenial and caudal cingulate cortex as well as auditory processing regions in the superior temporal cortex. The granular region on the lateral convexity had the most extensive connections. Based on its architectonics and functionality, it resembled areas 12/45 in macaques. It had connections with high-order visual processing regions in the inferotemporal cortex and posterior parietal cortex, higher-order auditory and polymodal processing regions in the superior temporal cortex. In addition it had extensive connections with limbic regions including the amygdala, parahippocampal cortex, cingulate, and retrosplenial cortex.

Hippocampal Network Connectivity and Activation Differentiates Post-Traumatic Stress Disorder From Generalized Anxiety Disorder

“…Lu et al (2012) demonstrated in rats that the default-mode network not only exists but also includes homologues of key structures noted in our work and that of others (Poppenk and Moscovitch, 2011) (eg, anterior cingulate cortex, retrosplenial cortex, and the dorsal hippocampus), which further strengthens the basis for parcellating hippocampus along its longitudinal axis. As such, converging evidence from noninvasive neuroimaging methods, along with those based on comparative anatomy techniques (ie, tract tracing) in rats (Van Groen and Wyss, 2003) and monkeys (Aggleton et al, 2012;Roberts et al, 2007), together provide support for the homology of hippocampal subdivisions that are the basis for this study (dorsal/ventral and posterior/anterior, respectively).…”

Regional inactivations of primate ventral prefrontal cortex reveal two distinct mechanisms underlying negative bias in decision making

“…The vlPFC region targeted here (area 12, including 12l, 12m, and 12o) sends projections to both the mPFC and OFC (28,29), but the relative contribution of these projections is unknown. However, although mPFC manipulations have been shown to cause immediate alterations in cost-benefit decision making (6), inactivation of the OFC in the present study did not, making it unlikely that interactions between vlPFC and antOFC were contributing to performance.…”

“…Anesthesia was monitored clinically and by pulse oximetry with capnography. Cannulae (Plastics One) were implanted into the vlPFC [double 6-mm-long cannulae, 1 mm apart, anteroposterior (AP) + 17.25/18.25, lateromedial (LM) adjusted in situ to give a depth greater than 3 mm at 8 0 ] or the antOFC (single 6-mm-long cannula, AP + 17, LM ± 3) having been adjusted where necessary in situ according to cortical depth (28). In the antOFC-cannulated animals, amygdala [single 14-mm-long cannula, AP + 9.3, LM ± 5.6, ventral (V) + 5] and anterior hippocampal (double 15-mm-long cannula, 1 mm apart, AP + 6, LM ± 5.75/7.75, V + 5) cannulae were added separately in an additional surgery.…”

Pleasure Rather Than Salience Activates Human Nucleus Accumbens and Medial Prefrontal Cortex

“…First, to investigate the reward-nonspecific (or saliency-driven) perspective of mesolimbic function, we determine whether unpleasant pictures activate the NAc and mPFC to the same degree as pleasant pictures. We include mPFC in this examination because it is a dense cortical site of NAc interconnectivity (Ferry et al 2000;Roberts et al 2007) and is correlated with NAc activity in human reward studies (Knutson et al 2003;Rogers et al 2004). We also examine the sensitivity of NAc to pictures of equal valence, but varying emotional arousal, to explore whether the structure's graded responsivity to abstract reward predictors (Abler et al 2006;Knutson et al 2005;Preuschoff et al 2006) extends to inherently emotionevoking stimuli.…”