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Encyclopedia > Orbitofrontal cortex
Brain: Orbitofrontal cortex
Approximate location of the OFC shown on a saggital MRI
Orbital surface of left frontal lobe.
Latin '
Gray's subject #189 822
Part of
Components
Artery
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Acronym(s) {{{Acronym}}}
NeuroNames hier-73
MeSH [1]
Dorlands/Elsevier {{{DorlandsPre}}}/{{{DorlandsSuf}}}

The orbitofrontal cortex (OFC) is a region of association cortex of the human brain involved in cognitive processes such as decision making. This region is named based upon its location within the frontal lobes, resting above the orbits of the eyes. Because of its functions in emotion, the orbitofrontal cortex is considered to be a part of the limbic system. Image File history File links Download high resolution version (705x672, 73 KB) Summary Author: Paul Wicks Source: My head! MRI Obtained in a 1. ... Image File history File links Gray729. ... Latin is an ancient Indo-European language originally spoken in the region around Rome called Latium. ... NeuroNames is a system of nomenclature for the brain and related structures. ... Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. ... Elseviers logo Elsevier, the worlds largest publisher of medical and scientific literature, forms part of the Reed Elsevier group. ... Location of the cerebral cortex Slice of the cerebral cortex, ca. ... The human brain. ... Look up Cognition in Wiktionary, the free dictionary. ... Decision making is the cognitive process of selecting a course of action from among multiple alternatives. ... The frontal lobe is an area in the brain of vertebrates. ... In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. ... This article or section does not cite its references or sources. ... It has been suggested that Feeling be merged into this article or section. ... The limbic system within the brain. ...

Contents


Normal functioning of the OFC

The OFC is thought to regulate planning behavior associated with sensitivity to reward and punishment. [1]. There are two themes of evidence to support this theory; research in healthy participants, and research in patients with damage to the OFC.


Research methods examining OFC dysfunction

  • The visual discrimination test[2] has two components: reversal learning and extinction. In "reversal learning", the participant is presented with one of two pictures, A and B. They learn that they will be rewarded if they press a button when picture A is displayed, but punished if they press the button when picture B is displayed. Once this rule has been established, the rule swaps. In other words, now it is correct to press the button for picture B, not picture A. Most healthy participants pick up on this rule reversal almost immediately, but patients with OFC damage continue to respond to the original pattern of reinforcement although they are now being punished for persevering with it. Rolls et al noted that this pattern of behaviour was particularly unusual given that the patients reported that they understood the rule.
  • The second component of the test is "extinction". Again, participants learn to press the button for picture A but not picture B. However this time, instead of the rules reversing, the rule changes altogether. Now the participant will be punished for pressing the button in response to either picture. The correct response is not to press the button at all, but people with OFC dysfunction find it difficult to resist the temptation to press the button despite being punished for it.
  • The Iowa gambling task is a simulation of real life decision-making[1] which is widely used in research of cognition and emotion. Participants are presented with 4 virtual decks of cards on a computer screen. They are told that each time they choose a card they will win some game money. Every so often, however, when they choose a card they will win money, but will also lose some money too. They are told that the aim of the game is to win as much money as possible. The task is meant to be opaque, i.e. participants are not meant to consciously work out the rule, and they are supposed to choose cards based on their "gut reaction". Two of the decks are "bad decks", which means that, over a long enough time, they will make a net loss; the other two decks are "good decks" and will make a net gain over time. Most healthy participants sample cards from each deck, and after about 40 or 50 selections are fairly good at sticking to the good decks. Patients with OFC dysfunction, however, continue to perseverate with the bad decks, sometimes even though they know that they are losing money overall. Concurrent measurement of galvanic skin response shows that healthy participants show a "stress" reaction to hovering over the bad decks after only 10 trials, long before conscious sensation that the decks are bad. By contrast, patients with OFC dysfunction never develop this physiological reaction to impending punishment. Bechara and his colleagues explain this in terms of the somatic marker hypothesis. The Iowa gambling task is currently being used by a number of research groups (including the Institute of Psychiatry and Institute of Neurology) using fMRI to investigate which brain regions are activated by the task in healthy volunteers as well as clinical groups with conditions such as schizophrenia and obsessive compulsive disorder.
  • The Faux pas test is a series of vignettes recounting a social occasion where someone said something they shouldn't have said, or something awkward. The participant's task is to identify what was said that was awkward, why it was awkward, how people would have felt in reaction to the faux pas, and a factual control question. Although first designed for use in people on the autistic spectrum[3], the test is also sensitive to patients with OFC dysfunction, who cannot judge when something socially awkward has happened despite appearing to understand the story perfectly well.

The Iowa gambling task is a psychological task thought to simulate real-life decision-making. ... Decision making is the cognitive process leading to the selection a course of action among alternatives. ... It has been suggested that this article or section be merged into Emotion. ... Galvanic skin response (or GSR), also known as electrodermal response (EDR) or psychogalvanic reflex (PGR), is a method of measuring the electrical resistance of the skin and interpreting it as an image of activity in certain parts of the body. ... Front doors of the Institute of Psychiatry // Introduction The Institute of Psychiatry (IOP) is a research institution dedicated to discovering what causes mental health problems and diseases of the brain. ... Functional Magnetic Resonance Imaging (or fMRI) describes the use of MRI to measure hemodynamic signals related to neural activity in the brain or spinal cord of humans or other animals. ... For other things named OCD, see OCD (disambiguation). ... The autistic spectrum (sometimes referred to as the autism spectrum) is a developmental and behavioral syndrome that results from certain combinations of traits. ...

Everyday consequences of damage to the OFC

Destruction of the OFC through acquired brain injury typically leads to a pattern of disinhibited behaviour. Examples include swearing excessively, hypersexuality, poor social interaction, compulsive gambling, excessive alcohol / smoking / drug use and poor empathising ability. Disinhibited behaviour by patients with some forms of frontotemporal dementia is thought to be caused by degeneration of the OFC[4]. Patients with damage to the OFC tend to make rash decisions and typically manage their finances poorly. A neurological condition, Acquired Brain Injury (or simply ABI) is damage to the brain after birth. ... Fronto-temporal dementias selectively affect the frontal lobe of the brain. ...


References

  1. ^ a b Bechara A, Damasio AR, Damasio H, Anderson SW. Insensitivity to future consequences following damage to human prefrontal cortex. Cognition 1994; 50: 7-15.
  2. ^ Rolls ET, Hornak J, Wade D, McGrath J. Emotion-related learning in patients with social and emotional changes associated with frontal lobe damage. J Neurol Neurosurg Psychiatry 1994; 57: 1518-1524.
  3. ^ Stone VE, Baron-Cohen S, Knight RT. Frontal Lobe Contributions to Theory of Mind. Journal of Medical Investigation 1998a; 10: 640-656.
  4. ^ Snowden JS, Bathgate D, Varma A, Blackshaw A, Gibbons ZC, Neary D. Distinct behavioural profiles in frontotemporal dementia and semantic dementia. J Neurol Neurosurg Psychiatry 2001; 70: 323-332.

See also

Phineas P. Gage (1823 – May 21, 1860) was a railroad construction worker who suffered an unusual kind of traumatic brain injury which inflicted severe damage to parts of his frontal brain during a work accident. ...

External links

Human brain - Limbic system - edit
Amygdala | Cingulate gyrus | Fornicate gyrus | Hippocampus | Hypothalamus | Mammillary body | Nucleus accumbens | Orbitofrontal cortex | Parahippocampal gyrus
Telencephalon (cerebrum, cerebral cortex, cerebral hemispheres) - edit

primary sulci/fissures: medial longitudinal, lateral, central, parietoöccipital, calcarine, cingulate The human brain. ... The limbic system within the brain. ... Location of the amygdala in the human brain The amygdala (Latin, corpus amygdaloideum) is an almond-shaped set of neurons located deep in the brains medial temporal lobe. ... Cingulate gyrus is a gyrus in the medial part of the brain. ... The Fornicate Gyrus is connected to the amydala, the mid region of the parietal region of the skull. ... The hippocampus is located in the medial temporal lobe of the brain. ... In the anatomy of mammals, the hypothalamus is a region of the brain located below the thalamus, forming the major portion of the ventral region of the diencephalon and functioning to regulate certain metabolic processes and other autonomic activities. ... The mammillary bodies (Latin: corpus mamillare) are a pair of small round bodies in the brain forming part of the limbic system. ... The nucleus accumbens (also known as the accumbens nucleus or nucleus accumbens septi) is a collection of neurons located where the head of the caudate and the anterior portion of the putamen meet just lateral to the septum pellucidum. ... . ... The telencephalon (te-len-seff-a-lon) is the technical name for a large region within the brain which is attributed many functions, which some groups would class as unique features which make humans stand out from other species. ... Location of the cerebral cortex Slice of the cerebral cortex, ca. ... Human brain viewed from above, showing cerebral hemispheres. ... A sulcus (pl. ... The medial longitudinal fissure is the deep groove which separates the two hemispheres of the vertebrate brain. ... Lateral sulcus The lateral sulcus (also called Sylvian fissure or lateral fissure) is one of the most prominent structures of the human brain. ... Central sulcus of the human brain. ... Only a small part of the Parietoöccipital Fissure (or parieto-occipital sulcus) is seen on the lateral surface of the hemisphere, its chief part being on the medial surface. ... The calcarine fissure (or calcarine sulcus) is on the medial surface of the hemisphere. ... Categories: Stub | Cerebrum ...


frontal lobe: precentral gyrus (primary motor cortex, 4), precentral sulcus, superior frontal gyrus (6, 8), middle frontal gyrus (46), inferior frontal gyrus (Broca's area, 44-pars opercularis, 45-pars triangularis), prefrontal cortex (orbitofrontal cortex, 9, 10, 11, 12, 47) The frontal lobe is an area in the brain of vertebrates. ... The precentral gyrus (a. ... The primary motor area is a group of networked cells in mammalian brains that controls movements of specific body parts associated with cell groups in that area of the brain. ... Brodmann area 4 of human brain. ... Precentral sulcus of the human brain. ... Superior frontal gyrus of the human brain. ... Categories: Stub | Cerebrum ... // Human Brodmann area 8, or BA8, is part of the frontal cortex in the human brain. ... Middle frontal gyrus of the human brain. ... // Where is it? Brodmann area 46, or BA46, is part of the frontal cortex in the human brain. ... Inferior frontal gyrus of the human brain. ... Brocas area is the section of the human brain (in the opercular and triangular sections of the inferior frontal gyrus of the frontal lobe of the cortex) that is involved in language processing, speech production and comprehension. ... Categories: Stub | Cerebrum ... The Pars Opercularis is part of the inferior frontal gyrus and is part of the mirror neurons. ... Categories: Stub | Cerebrum ... The Pars triangularis is a portion of the inferior frontal gyrus. ... The prefrontal cortex is the anterior part of the frontal lobes of the brain, lying in front of the motor and premotor areas. ... Categories: Stub | Cerebrum ... Categories: Stub | Cerebrum ... Categories: Stub | Cerebrum ... The term Brodmann area 12 refers to a subdivision of the cerebral cortex of the guenon defined on the basis of cytoarchitecture. ... Where is it? Brodmann area 47, or BA47, is part of the frontal cortex in the human brain. ...


parietal lobe: postcentral sulcus, postcentral gyrus (1, 2, 3, 43), superior parietal lobule (5), inferior parietal lobule (39-angular gyrus, 40), precuneus (7), intraparietal sulcus The parietal lobe is a lobe in the brain. ... Postcentral sulcus of the human brain. ... The lateral postcentral gyrus is a prominent structure in the parietal lobe of the human brain and an important landmark. ... This page may meet Wikipedias criteria for speedy deletion. ... The superior parietal lobule is bounded in front by the upper part of the postcentral sulcus, but is usually connected with the posterior central gyrus above the end of the sulcus; behind it is the lateral part of the parietoöccipital fissure, around the end of which it is joined... Brodmann area 5 is part of the parietal cortex in the human brain. ... The inferior parietal lobule (subparietal district or lobule) lies below the horizontal portion of the intraparietal sulcus, and behind the lower part of the postcentral sulcus. ... Categories: Stub | Cerebrum ... The angular gyrus is a region of the brain that lies near the superior edge of the temporal lobe, and immediately posterior to the supramarginal gyrus; it is involved in the recognition of visual symbols. ... Brodmann area 40, or BA40, is part of the parietal cortex in the human brain. ... The precuneus is a structure in the brain positioned above the cuneus and located in the parietal lobe. ... Categories: Stub | Cerebrum ... The lateral surface of the parietal lobe is cleft by a well-marked furrow, the intraparietal sulcus of Turner, which consists of an oblique and a horizontal portion. ...


occipital lobe: primary visual cortex (17), cuneus, lingual gyrus, 18, 19 (18 and 19 span whole lobe) The occipital lobe is the visual processing center of the mammalian brain. ... Visual cortex is the term applied to both the primary visual cortex (also known as striate cortex or V1) and upstream visual cortical areas also known as extrastriate cortical areas (V2, V3, V4, V5). ... Cuneus (Latin for wedge; plural, cunei), the architectural term applied to the wedge-shaped divisions of the Roman theatre separated by the scalae or stairways; see Vitruvius v. ... The lingual gyrus of the occipital lobe lies between the calcarine fissure and the posterior part of the collateral fissure; behind, it reaches the occipital pole; in front, it is continued on to the tentorial surface of the temporal lobe, and joins the hippocampal gyrus. ... Categories: Stub | Cerebrum ... Brodmann area 19 is shown in yellow in this image which also shows ares 17 (red) and 18 (orange) Brodmann area 19, or BA19, is part of the occipital lobe cortex in the human brain. ...


temporal lobe: transverse temporal gyrus (41-42-primary auditory cortex), superior temporal gyrus (38, 22-Wernicke's area), middle temporal gyrus (21), inferior temporal gyrus (20), fusiform gyrus (36, 37) The temporal lobes are part of the cerebrum. ... The transverse temporal gyri (also called Heschls gyri) are found in the area of primary auditory cortex in the superior temporal gyrus of the human brain. ... The primary auditory cortex is the region of the brain that is responsible for processing of auditory (sound) information. ... Superior temporal gyrus of the human brain. ... Categories: Stub | Cerebrum ... On the left side of the brain is an area called Brodmann’s area 22, that help generate and help the understanding of individual words, and on the right side of the brain it helps tell the difference between melody, pitch, and sound intensity. ... Approximate location of Wernickes area highlighted in gray Wernickes area is a part of the human brain that forms part of the cortex, on the left posterior section of the superior temporal gyrus, posterior to the primary auditory cortex, on the central sulcus (part of the brain where... The location in the brain of the middle temporal gyrus Middle temporal gyrus is a gyrus in the brain on the Temporal lobe. ... Categories: Stub | Cerebrum ... Function of Inferior Temporal Gyrus The Inferior Temporal Gyrus, also known as Brocas area, carries out many tasks, and is mainly responsible for its task in phoenetical analysis for reading. ... Categories: Stub | Cerebrum ... Please observe: the above picture was copied from this fantastic brain atlas The Fusiform gyrus is part of the temporal lobe. ... This area is known as ectorhinal area 36, and it refers to a subdivision of the cytoarchitecturally defined temporal region of cerebral cortex. ... Categories: Stub | Cerebrum ...


limbic lobe/fornicate gyrus: cingulate cortex/cingulate gyrus, anterior cingulate (24, 32, 33), posterior cingulate (23, 31),
isthmus (26, 29, 30), parahippocampal gyrus (piriform cortex, 25, 27, 35), entorhinal cortex (28, 34) The limbic system is a group of brain structures that are involved in various emotions such as aggression, fear, pleasure and also in the formation of memory. ... The Fornicate Gyrus is connected to the amydala, the mid region of the parietal region of the skull. ... The cingulate cortex is part of the brain and situated roughly in the middle of the cortex. ... Cingulate gyrus is a gyrus in the medial part of the brain. ... Grays FIG. 727– Medial surface of left cerebral hemisphere. ... 24 - ventral anterior cingulate (area cingularis anterior ventralis). ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ... This area is known as pregenual area 33, and it refers to a subdivision of the cytoarchitecturally defined cingulate region of cerebral cortex. ... The Cingulum is a collection of nerve fibres following a long, arcuate course superior to and around to posterior to the Corpus callosum. ... Brodmann area 23 (BA23) is a region in the brain corresponding to some portion of the posterior cingulate cortex. ... This area is known as dorsal posterior cingulate area 31, and it refers to a subdivision of the cytoarchitecturally defined cingulate region of cerebral cortex. ... In anatomy, isthmus refers to a constriction between organs. ... This article may be too technical for most readers to understand. ... This area is known as granular retrolimbic area 29, and it refers to a cytoarchitecturally defined portion of the retrosplenial region of the cerebral cortex. ... This area is known as agranular retrolimbic area 30, and it refers to a subdivision of the cytoarchitecturally defined retrosplenial region of the cerebral cortex. ... . ... In anatomy of animals, the piriform cortex, or pyriform cortex is a region in the brain. ... // Human Brodmann area 25 (BA25) is an area in the cerebral cortex of the brain and delineated based on its cytoarchitectonic characteristics. ... The term area 27 of Brodmann-1909 refers to a cytoarchitecturally defined cortical area that is a rostral part of the PARAHIPPOCAMPAL GYRUS of the guenon (Brodmann-1909). ... // Human This area is known as perirhinal area 35, and it refers to a subdivision of the cytoarchitecturally defined hippocampal region of the cerebral cortex. ... The entorhinal cortex (EC) is an important memory center in the brain. ... // Guenon The term Brodmann area 28 refers to a subdivision of the cerebral cortex of the guenon defined on the basis of cytoarchitecture. ... You have new messages. ...


subcortical/insular cortex: rhinencephalon, olfactory bulb, corpus callosum, lateral ventricles, septum pellucidum, ependyma, internal capsule, corona radiata, external capsule The insular cortex (also often referred to as just the insula) is a structure of the human brain. ... In animal anatomy, the rhinencephalon is a part of the brain involved with olfaction. ... Vesalius Fabrica, 1543. ... Grays FIG. 733– Corpus callosum from above. ... The ventricular system is a fluid conducting system within the brain. ... The septum pellucidum, also called the septum lucidum, is a thin, triangular, vertical membrane that separates the lateral ventricles of the brain. ... Ependyma is the thin epithelial membrane lining the ventricular system of the brain and the spinal cord canal Categories: Anatomy stubs | Physiology ... The internal capsule is an area of white matter in the brain that separates the caudate nucleus and the thalamus from the lenticular nucleus. ... The corona radiata surround an ovum or unfertilized egg cell, and consist of two or three strata (layers) of follicular cells. ... The external capsule is a series of white matter fiber tracts in the brain. ...


hippocampal formation: dentate gyrus, hippocampus, subiculum The location of the hippocampus in the human brain. ... The dentate gyrus is part of the hippocampal formation. ... The hippocampus is located in the medial temporal lobe of the brain. ... The subiculum (Latin: support) forms the most inferior portion of the human hippocampus. ...


basal ganglia: striatum (caudate nucleus, putamen), lentiform nucleus (putamen, globus pallidus), claustrum, extreme capsule, amygdala, nucleus accumbens To meet Wikipedias quality standards, this article or section may require cleanup. ... Coronal slices of human brain showing the basal ganglia, globus pallidus: external segment (GPe), subthalamic nucleus (STN), globus pallidus: internal segment (GPi), and substantia nigra (SN). ... Grays Fig. ... The putamen is a structure in the middle of the brain, forming the striatum together with the caudate nucleus. ... The lentiform nucleus or lenticular nucleus describes the putamen and the globus pallidus within the basal ganglia. ... The putamen is a structure in the middle of the brain, forming the striatum together with the caudate nucleus. ... The globus pallidus (Latin for pale body) is a sub-cortical structure in the brain. ... The claustrum is a thin layer of grey matter lying between the extreme capsule and external capsule in the brain. ... The extremem capsule is a series of white matter fiber tracts in the brain. ... Location of the amygdala in the human brain The amygdala (Latin, corpus amygdaloideum) is an almond-shaped set of neurons located deep in the brains medial temporal lobe. ... The nucleus accumbens (also known as the accumbens nucleus or nucleus accumbens septi) is a collection of neurons located where the head of the caudate and the anterior portion of the putamen meet just lateral to the septum pellucidum. ...


Some categorizations are approximations, and some Brodmann areas span gyri.

  Results from FactBites:
 
Prefrontal cortex - Wikipedia, the free encyclopedia (775 words)
The prefrontal cortex is the anterior part of the frontal lobes of the brain, lying in front of the motor and premotor areas.
Cytoarchitectonically, it is defined by the presence of an internal granular layer IV (in contrast to the agranular premotor cortex).
The classic case of earlier studies of prefrontal cortex function involved a railroad supervisor of construction - one Phineas Gage - who in 1848, despite a metal rod piercing his left cheek and exiting the top of his head, survived the incident and healed.
BioMed Central | Full text | Serial pathways from primate prefrontal cortex to autonomic areas may influence emotional ... (5272 words)
Orbitofrontal and medial prefrontal cortices are in a strategic position to influence the expression of emotions through their robust and bidirectional connections with the amygdala (e.g., [23-25],[30-36]).
The pathways from orbitofrontal cortex to the amygdala are equally robust and specific, terminating heavily on presumed inhibitory neurons in the intercalated masses [24] (Fig.
The nomenclature for the prefrontal cortex is according to the map of Barbas and Pandya [62], as modified from the map of Walker [63].
  More results at FactBites »

 

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