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Rostral Prefrontal Cortex (Brodmann Area 10): Metacognition in the Brain

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Abstract

The study of rostral prefrontal cortex (PFC) must count now as perhaps the fastest-growing new area of cognitive neuroscience. Until approximately 10 years ago, virtually nothing was known about this huge brain region (actually the largest architectonic subregion of the PFC). Now we have evidence that stretches across neuroanatomy, anthropology, brain development, cognitive neuroscience, neuropsychology, neuropsychiatry (adults and children), and, most recently, even behavioral neuroscience (Tsujimoto, Genovesio, & Wise, 2011). The purpose of this chapter is to lay out, in as straightforward a way as possible, the current state of our knowledge about this fascinating brain region. We will conclude by suggesting that perhaps the best description for the overall function of this brain region in humans would be that it is a hub formetacognition.
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... Regarding the motor domain, external IP deals with behavior that requires interaction with external influences, while internal IP occurs during self-generated or -paced movements. A series of earlier studies by Burgess et al. proposed that when the human mind is occupied with a given task, it involves high-level processes that govern the allocation of processing resources (Burgess et al., 2007a,b;Burgess and Wu, 2013). In particular, such processes engage an executive control system centered on the rostral prefrontal cortex (also known as the frontopolar cortex) to evaluate the ongoing behavior and bias the allocation of processing resources toward the IP relevant to the current behavioral goal, termed as executive resource allocation. ...
... Therefore, our findings resonate with previous evidence reporting similar brain patterns with increased rmPFC activation and indistinct sensorimotor activities during externally oriented tasks, relative to internally-oriented ones (Gilbert et al., 2006(Gilbert et al., , 2007Henseler et al., 2011). The engagement of the rmPFC in a high-order system that monitors behavioral demands and governs the allocation of processing resources toward external IP has been demonstrated (Gilbert et al., 2006;Burgess et al., 2007a;Simons et al., 2008;Henseler et al., 2011;Burgess and Wu, 2013). The rostral PFC, including the rostromedial region, is anatomically interconnected with supramodal cortices in the PFC, anterior temporal cortex, and cingulate cortex (Morán et al., 1987;Arikuni et al., 1994;Petrides and Pandya, 1999). ...
... The above findings suggest that the increased ventral rmPFC activation of ROB vs. RES is unlikely to represent task difficulty effect across conditions. Our results are supported by those of previous studies suggesting that the most anterior part of PFC, corresponding to the ventral rmPFC in this study, plays a critical role in biasing the allocation of processing resources toward the external IP according to current behavioral demands (Gilbert et al., 2006(Gilbert et al., , 2007Burgess et al., 2007b;Henseler et al., 2011;Burgess and Wu, 2013). A posterior-toanterior organization in hierarchical control of cognition by the PFC has been proposed (Koechlin and Summerfield, 2007;Rahnev, 2017). ...
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Assistive exoskeleton robots are being widely applied in neurorehabilitation to improve upper-limb motor and somatosensory functions. During robot-assisted exercises, the central nervous system appears to highly attend to external information-processing (IP) to efficiently interact with robotic assistance. However, the neural mechanisms underlying this process remain unclear. The rostromedial prefrontal cortex (rmPFC) may be the core of the executive resource allocation that generates biases in the allocation of processing resources toward an external IP according to current behavioral demands. Here, we used functional near-infrared spectroscopy to investigate the cortical activation associated with executive resource allocation during a robot-assisted motor task. During data acquisition, participants performed a right-arm motor task using elbow flexion-extension movements in three different loading conditions: robotic assistive loading (ROB), resistive loading (RES), and non-loading (NON). Participants were asked to strive for kinematic consistency in their movements. A one-way repeated measures analysis of variance and general linear model-based methods were employed to examine task-related activity. We demonstrated that hemodynamic responses in the ventral and dorsal rmPFC were higher during ROB than during NON. Moreover, greater hemodynamic responses in the ventral rmPFC were observed during ROB than during RES. Increased activation in ventral and dorsal rmPFC subregions may be involved in the executive resource allocation that prioritizes external IP during human-robot interactions. In conclusion, these findings provide novel insights regarding the involvement of executive control during a robot-assisted motor task.
... Several studies in healthy individuals have suggested the role of the Frontal Pole (FP) in meta-cognitive function Burgess and Wu, 2013;Chua et al., 2014;Fleming et al., 2010;Schmitz and Johnson, 2007;Volle et al., 2010). The FP, also called Broadman Area 10 (BA 10) /FP) which is the rostral-most part of the human brain, is possibly the largest cytoarchitectonic area of the human prefrontal cortex (PFC) (Ramnani and Owen, 2004) It has been proven to perform a crucial part in several facets of the intricate human cognitive process (Gilbert et al., 2006), including multitasking, processing of 'cognitive branching' based on reward expectation (Koechlin and Hyafil, 2007), time-and event-based prospective memory (Okuda et al., 2007) and conflict resolution (Posner et al., 2006). ...
... Hence, our study finding of relation with composite index with left FP volume, in the absence of relation with SR or SC could be due to the psychometric properties of the scale or due to a specific function of the FP. FP has a unique role of integrating several disparate mental processes (Burgess and Wu, 2013), a function considered fundamental to higher-level cognition in humans. It is crucial to notice that left but not right FP was shown to be critical for this function (Bunge et al., 2009) as our study findings. ...
Article
Objective Cognitive insight comprising self-reflection and self-certainty is an important determinant of functional outcomes in Schizophrenia. The neural correlates of cognitive insight in Schizophrenia are underexamined. The frontal pole (FP) is implicated in metacognitive function in healthy individuals, but its role is not well examined in Schizophrenia. We had earlier reported the relationship between Frontal pole volumes and cognitive insight in a small sample of only male patients. Hence, we studied this relationship in an independent sample of schizophrenia patients and healthy controls. Methods We examined 41 healthy volunteers (HV) and 57 patients with Schizophrenia (SCZ). We used a previously validated manual morphometric method to perform FP parcellation on images obtained from a 3 T scanner and calculated the volumes. Cognitive insight was measured using Beck’s Cognitive insight scale (BCIS). To assess the relationship between FP volumes and BCIS scores, multiple linear regression analyses were performed. Results In the overall sample, age, years of education, and intracranial volume were significant predictors of BCIS scores. Within the SCZ group, age and left FP volume were significant predictors of BCIS composite scores and age, ICV for BCIS-self certainty. There was no significant relationship between age and FP volumes in either SCZ or HV group. Discussion The current study in an independent sample further supports the critical role of the frontal pole in cognitive insight, earlier reported by us. As cognitive insight has a vital role in functional outcome, our findings have potential clinical implications.
... Functional imaging studies in healthy individuals (HV) have implicated the frontal pole (FP), another sub-division of the prefrontal cortex (PFC) in self-reflective processes (Amodio and Frith, 2006). This region which is also called the rostral PFC, frontopolar cortex, or anterior PFC, mainly comprises of Brodmann area 10 (BA 10) (Burgess et al., 2013). In humans, it has progressively developed during the evolutionary process to become the single largest sub-region of the PFC (Semendeferi et al., 2001;Semendeferi et al., 2011). ...
... In humans, it has progressively developed during the evolutionary process to become the single largest sub-region of the PFC (Semendeferi et al., 2001;Semendeferi et al., 2011). In addition to self-referential processing, the FP is also implicated in numerous critical and complex human cognitive functions including prospective memory, multi-tasking, mentalizing (Burgess and Wu, 2013;Gilbert et al., 2006). Significant abnormalities in the FP have been demonstrated in both SCZ and their at-risk relatives (John et al., 2009;Rosso et al., 2010;Scarr et al., 2018). ...
Article
Absence of insight owing to impaired self-reflection and lack of touch with reality is a hallmark of schizophrenia. Functional imaging studies in healthy individuals have implicated the frontal pole (FP), sub-division of the prefrontal cortex in self-reflective processes. Despite the significance of self-referential processing in the pathogenesis of schizophrenia, the relationship between FP volume and cognitive insight in this disorder is underexplored. We examined the relationship between cognitive insight and volume of FP using precise manual morphometry of high resolution magnetic resonance images in 19 schizophrenia patients (SCZ) and 21 healthy-volunteers (HV). The manual morphometry technique was replicated from a previous study based on a cytoarchitectonically and functionally valid definition of FP and cognitive insight was measured using Beck's cognitive insight scale. Left frontal pole volume was a significant predictor of self-reflection sub-score of Beck's cognitive insight scale (β=0.68; t = 2.86; p = 0.01). A significant inverse relationship between age and bilateral FP volumes was noted in HV (left FP - r=-0.45; p = 0.04; right FP - r=-0.57; p = 0.008) but not in SCZ (p>0.05). Our findings provide anatomical substrates to devise intervention strategies targeting cognitive insight, thereby improving treatment adherence and functional outcomes.
... The lPFC in general, and the aPFC in particular, appears to support a variety of highlevel cognitive processes that require the use of specific task rules (Bunge, 2004;Bunge and Zelazo, 2006;Burgess and Wu, 2012). According to these accounts of lPFC function, increased connectivity between the IFJ and the lPFC is likely to result from the increased demand to manage currently irrelevant task sets during mixed blocks. ...
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The ability to flexibly switch between tasks is key for goal-directed behavior and continues to improve in late childhood. Children's task switching difficulties are thought to reflect less efficient engagement of sustained and transient control processes, resulting in lower performance on blocks that intermix tasks (sustained demand) and trials that require a task switch (transient demand). Sustained and transient control processes are associated with frontoparietal regions, which develop throughout childhood and may contribute to task switching development. We examined age differences in the modulation of frontoparietal regions by sustained and transient control demands in children (8-11 years) and adults. Children showed greater performance costs than adults, especially under sustained demand, along with less upregulation of sustained and transient control activation in a set of frontoparietal regions. Compared to adults, children showed greater increases in connectivity between the inferior frontal junction (IFJ) and lateral prefrontal cortex (lPFC) from single to mixed blocks. For children whose sustained activation was less adult-like, increased IFJ-lPFC connectivity was associated with better performance. Children with more adult-like sustained activation showed the inverse effect. Taken together, these results suggest that the configuration of regions that control task switching effectively undergoes developmental changes in later childhood.
... It may be that this brain region sets the parameters to be used by the lateral prefrontal, orbitofrontal and anterior cingulate cortices in the evaluation of choice options. This is consistent with Burgess and Wu's (2013) conclusion that the overall function of the rostral prefrontal cortex is as a "hub for metacognition" (their italics: p. 524). In this article, I propose that something similar happens with regard to the effect of severe exercise on cognition. ...
Article
An interoception model for the acute exercise-cognition interaction is presented. During exercise following the norepinephrine threshold, interoceptive feedback induces increased tonic release of extracellular catecholamines, facilitating phasic release hence better cognitive performance of executive functions. When exercise intensity increases to maximum, the nature of task-induced norepinephrine release from the locus coeruleus is dependent on interaction between motivation, perceived effort costs and perceived availability of resources. This is controlled by interaction between the rostral and dorsolateral prefrontal cortices, orbitofrontal cortex, anterior cingulate cortex and anterior insula cortex. If perceived available resources are sufficient to meet predicted effort costs and reward value is high, tonic release from the locus coeruleus is attenuated thus facilitating phasic release, therefore cognition is not inhibited. However, if perceived available resources are insufficient to meet predicted effort costs or reward value is low, tonic release from the locus coeruleus is induced, attenuating phasic release. As a result, cognition is inhibited, although long-term memory and tasks that require switching to new stimuli-response couplings are probably facilitated.
... Cortical areas 10r, a24, p32, and s32 overlap with the ALE in the region of the anterior cingulate cortex, which has been identified as a com- Area 10r is one of several newly described divisions of the original Brodmann Area 10 , which expanded the entire frontal polar cortex from the medial superior frontal gyrus to the dorsolateral prefrontal cortex (Burgess & Wu, 2013;Peng et al., 2018). ...
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Background The default mode network (DMN) is an important mediator of passive states of mind. Multiple cortical areas, such as the anterior cingulate cortex, posterior cingulate cortex, and lateral parietal lobe, have been linked in this processing, though knowledge of network connectivity had limited tractographic specificity. Methods Using resting‐state fMRI studies related to the DMN, we generated an activation likelihood estimation (ALE). We built a tractographical model of this network based on the cortical parcellation scheme previously published under the Human Connectome Project. DSI‐based fiber tractography was performed to determine the structural connections between cortical parcellations comprising the network. Results Seventeen cortical regions were found to be part of the DMN: 10r, 31a, 31pd, 31pv, a24, d23ab, IP1, p32, POS1, POS2, RSC, PFm, PGi, PGs, s32, TPOJ3, and v23ab. These regions showed consistent interconnections between adjacent parcellations, and the cingulum was found to connect the anterior and posterior cingulate clusters within the network. Conclusions We present a preliminary anatomic model of the default mode network. Further studies may refine this model with the ultimate goal of clinical application.
... Lesions in the ventromedial orbitofrontal cortex (VMOFC) and FP have also been associated with value-based decision making and impulsivity (Berlin & Rolls, 2004;Gläscher et al., 2012;Noonan et al., 2017). According to the 'gateway hypothesis', the rostral prefrontal cortex plays an important role in the 'supervisory attentional gateway' system that enables switching between attending modes, either to the outside world or to the inner mental world (see Burgess & Wu, 2013). ...
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Attention, working memory, and executive control are commonly considered distinct cognitive functions with important reciprocal interactions. Lesion studies pioneered by Donald Stuss have demonstrated both overlap and dissociation in their behavioral expression and anatomical underpinnings. Here, we provide an overview of cognitive models as well as recent data from lesion studies and both invasive and noninvasive multimodal neuroimaging and brain stimulation, in order to provide an updated perspective on the relationship between attention, working memory, and executive control. Specifically, we address the functional and anatomical correspondence between these processes, toward the goal of identifying whether a lower dimensional theoretical framework should be employed to understand executive control (Karolis et al., 2019). We conclude by emphasizing that one avenue for moving the field, pioneered by Donald Stuss, forward consists of studying this low-dimensional space with a multi-method approach to identify converging evidence regarding the interaction between subfunctions, allowing to construct a model of executive control as the emergent consequence of efficient implementation of these processes.
... For instance, the gateway hypothesis of rostral prefrontal cortex (area 10) proposed by Burgess and colleagues (2007) suggests that different subregions of the most rostral parts of anterior PFC support stimulus-oriented processing and stimulus-independent attending. In general, activation in the medial aspects of anterior PFC is associated with increases in stimulus-oriented attending, and lateral anterior PFC (BA 10) activation increases accompany increases in stimulus-independent thought (e.g., Henseler et al., 2011; for review see Burgess and Wu, 2013). Stimulus-oriented attending processes would be involved when attending very closely to another person"s face, or looking for "tells" in their behaviour, whereas stimulus-independent processes would be used in problem-solving in open-ended situations, such as deciding for yourself whether now is the right time to lie, or how likely it is that another person might. ...
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Anterior prefrontal cortex (PFC; Brodmann area 10) activations are often, but not always, found in neuroimaging studies investigating deception, and the precise role of this area remains unclear. To explore the role of PFC in face-to-face deception, we invited pairs of participants to play a card game involving lying and lie detection while we used functional near infrared spectroscopy (fNIRS) to record brain activity in PFC. Participants could win points for successfully lying about the value of their cards or for detecting lies. We contrasted patterns of brain activation when the participants either told the truth or lied, when they were either forced into this or did so voluntarily, and when they either succeeded or failed to detect a lie. Activation in anterior PFC was found in both lie production and detection, unrelated to reward. Analysis of cross-brain activation patterns between participants identified areas of PFC where the lead player's brain activity was synchronized their partner's later brain activity. These results suggest that during situations that involve close interpersonal interaction, anterior PFC supports processing widely involved in deception, possibly relating to the demands of monitoring one's own, and other people's behaviour.
Article
Rostral PFC (area 10) activation is common during prospective memory (PM) tasks. But it is not clear what mental processes these activations index. Three candidate explanations from cognitive neuroscience theory are: (i) monitoring of the environment; (ii) spontaneous intention retrieval; (iii) a combination of the two. These explanations make different predictions about the temporal and spatial patterns of activation that would be seen in rostral PFC in naturalistic settings. Accordingly, we plotted functional events in PFC using portable fNIRS while people were carrying out a PM task outside the lab and responding to cues when they were encountered, to decide between these explanations. Nineteen people were asked to walk around a street in London, U.K. and perform various tasks while also remembering to respond to prospective memory (PM) cues when they detected them. The prospective memory cues could be either social (involving greeting a person) or non-social (interacting with a parking meter) in nature. There were also a number of contrast conditions which allowed us to determine activation specifically related to the prospective memory components of the tasks. We found that maintaining both social and non-social intentions was associated with widespread activation within medial and right hemisphere rostral prefrontal cortex (BA 10), in agreement with numerous previous lab-based fMRI studies of prospective memory. In addition, increased activation was found within lateral prefrontal cortex (BA 45 and 46) when people were maintaining a social intention compared to a non-social one. The data were then subjected to a GLM-based method for automatic identification of functional events (AIDE), and the position of the participants at the time of the activation events were located on a map of the physical space. The results showed that the spatial and temporal distribution of these events was not random, but aggregated around areas in which the participants appeared to retrieve their future intentions (i.e., where they saw intentional cues), as well as where they executed them. Functional events were detected most frequently in BA 10 during the PM conditions compared to other regions and tasks. Mobile fNIRS can be used to measure higher cognitive functions of the prefrontal cortex in “real world” situations outside the laboratory in freely ambulant individuals. The addition of a “brain-first” approach to the data permits the experimenter to determine not only when haemodynamic changes occur, but also where the participant was when it happened. This can be extremely valuable when trying to link brain and cognition.
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Sleep deprivation (SD) is a common condition and an important health concern. In addition to metabolic and cardiovascular risks, SD associates with decreases in cognitive performance. Neurovascular coupling (NVC, "functional hyperemia") is a critical homeostatic mechanism, which maintains adequate blood supply to the brain during periods of intensive neuronal activity. To determine whether SD alters NVC responses and cognitive performance, cognitive and hemodynamic NVC assessments were conducted prior to and 24 h post-SD in healthy young male individuals (n = 10, 27 ± 3 years old). Cognition was evaluated with a battery of tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB). Hemodynamic components of NVC were measured by transcranial Doppler sonography (TCD) during cognitive stimulation, dynamic retinal vessel analysis (DVA) during flicker light stimulation, and functional near infrared spectroscopy (fNIRS) during finger tapping motor task. Cognitive assessments revealed impairments in reaction time and sustained attention after 24 h of SD. Functional NIRS analysis revealed that SD significantly altered hemodynamic responses in the prefrontal cortex and somatosensory cortex during a motor task. NVC-related vascular responses measured by DVA and TCD did not change significantly. Interestingly, TCD detected decreased task-associated cerebral blood flow (CBF) in the right middle cerebral artery in sleep deprived participants. Our results demonstrate that 24 h of SD lead to impairments in cognitive performance together with altered CBF and hemodynamic components of cortical NVC responses.
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We have used positron emission tomography to study the functional anatomy of motor sequence learning. Subjects learned sequences of keypresses by trial and error using auditory feedback. They were scanned with eyes closed under three conditions: at rest, while performing a sequence that was practiced before scanning until overlearned, and while learning new sequences at the same rate of performance. Compared with rest, both sequence tasks activated the contralateral sensorimotor cortex to the same extent. Comparing new learning with performance of the prelearned sequence, differences in activation were identified in other areas. (1) Prefrontal cortex was only activated during new sequence learning. (2) Lateral premotor cortex was significantly more activated during new learning, whereas the supplementary motor area was more activated during performance of the prelearned sequence. (3) Activation of parietal association cortex was present during both motor tasks, but was significantly greater during new learning. (4) The putamen was equally activated by both conditions. (5) The cerebellum was activated by both conditions, but the activation was more extensive and greater in degree during new learning. There was an extensive decrease in the activity of prestriate cortex, inferotemporal cortex, and the hippocampus in both active conditions, when compared with rest. These decreases were significantly greater during new learning. We draw three main conclusions. (1) The cerebellum is involved in the process by which motor tasks become automatic, whereas the putamen is equally activated by sequence learning and retrieval, and may play a similar role in both. (2) When subjects learn new sequences of motor actions, prefrontal cortex is activated. This may reflect the need to generate new responses. (3) Reduced activity of areas concerned with visual processing, particularly during new learning, suggests that selective attention may involve depressing the activity of cells in modalities that are not engaged by the task.
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We propose that rostral prefrontal cortex (PFC; approximating area 10) supports a cognitive system that facilitates either stimulus-oriented (SO) or stimulus-independent (SI) attending. SO attending is the behaviour required to concentrate on current sensory input, whereas SI attending is the mental processing that accompanies self-generated or self-maintained thought. Regions of medial area 10 support processes related to the former, whilst areas of lateral area 10 support processes that enable the latter. Three lines of evidence for this ‘gateway hypothesis’ are presented. First, we demonstrate the predicted patterns of activation in area 10 during the performance of new tests designed to stress the hypothetical function. Second, we demonstrate area 10 activations during the performance of established functions (prospective memory, context memory), which should hypothetically involve the proposed attentional system. Third, we examine predictions about behaviour–activation patterns within rostral PFC that follow from the hypothesis. We show with meta-analysis of neuroimaging investigations that these predictions are supported across a wide variety of tasks, thus establishing a general principle for functional imaging studies of this large brain region. We then show that while the gateway hypothesis accommodates a large range of findings relating to the functional organization of area 10 along a medial–lateral dimension, there are further principles relating to other dimensions and functions. In particular, there is a functional dissociation between the anterior medial area 10, which supports processes required for SO attending, and the caudal medial area 10, which supports processes relating to mentalizing.
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The rostral prefrontal cortex (or Area 10) is a sizeable brain region that is especially large in humans compared with other animals, yet very little is known about what role it plays in cognition. This chapter contains three sections. The first reviews the existing empirical and theoretical evidence. The second presents a new theoretical account of its function that synthesises this evidence. The third section describes a recent series of experiments that demonstrate the plausibility of the theory. Rostral prefrontal cortex (rostral PFC) is identified as subserving a system that biases the relative influence of stimulus-oriented and stimulus-independent thought. This cognitive control function is used in a wide range of situations critical to competent human behaviour in everyday life, ranging from straightforward 'watchfulness' to complex activities such as remembering to carry out intended actions after a delay, multitasking, and aspects of recollection.
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One of the great successes of functional neuroimaging as a method has been to generate theories concerning the cognitive functions supported by rostral PFC (approximating Brodmann Area 10). But these ideas have developed largely without regard to the existing data available from human lesion studies, which should have provided valuable constraints on theorising. These data are outlined here, augmented by a meta-analysis of the work of Donald T. Stuss and colleagues. Rostral PFC lesions do not typically cause widespread cognitive deficits. But they often do cause marked deficits in a range of cognitive abilities which have hitherto received little attention from cognitive scientists. These include (but are not restricted to) prospective memory, multitasking, "metacognitive" control, and social behaviour. It is argued that functional neuroimaging practitioners of functional neuroimaging might wish to consider these data when interpreting, post-hoc, findings of haemodynamic change in rostral PFC.
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Information on the development and functions of rostral prefrontal cortex (PFC), or Brodmann area 10, has been gathered from different fields, from anatomical development to functional neuroimaging in adults, and put forward in relation to three particular cognitive and behavioural disorders. Rostral PFC is larger and has a lower cell density in humans than in other primates. It also has a large number of dendritic spines per cell and numerous connections to the supramodal cortex. These characteristics suggest that rostral PFC is likely to support processes of integration or coordination of inputs that are particularly developed in humans. The development of rostral PFC is prolonged, with decreases in grey matter and synaptic density continuing into adolescence. Functions attributed to rostral PFC, such as prospective memory, seem similarly to follow a prolonged development until adulthood. Neuroimaging studies have generally found a reduced recruitment of rostral PFC, for example in tasks requiring response inhibition, in adults compared with children or adolescents, which is consistent with maturation of grey matter. The examples of autism, attention-deficit-hyperactivity disorder, and schizophrenia show that rostral PFC could be affected in several disorders as a result of the susceptibility of its prolonged maturation to developmental abnormalities.
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The chapter describes the structural organization of the orbital cortex (OFC), together with the medial prefrontal cortex. It reviews previous areal maps of this cortex, and provides a description of architectonic divisions of the cortex based on analysis of eight staining methods in nonhuman primates and humans. Twenty-two areas were recognized, most of which are subdivisions of previously described areas. Distinct subregions were found ranging from several agranular insular areas in the posterior orbital region, through a dysgranular zone in the central region (subdivisions of area 12 and 13), to a granular region in more rostral portions of cortex (subdivisions of areas 10 and 11). The comparable regions in humans are presented with reference to stereotaxic space. An analysis of the comparable regions in rodents is also provided.
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