neuroanatomy Neuroanatomy is the study of the structure and organization of the nervous system. In contrast to animals with radial symmetry, whose nervous system consists of a distributed network of cells, animals with bilateral symmetry have segregated, defin ...

, the cingulum is a

nerve tract A nerve tract is a bundle of nerve fibers (axons) connecting nuclei of the central nervous system. In the peripheral nervous system this is known as a nerve, and has associated connective tissue. The main nerve tracts in the central nervous syste ...

– a collection of

axons An axon (from Greek ἄξων ''áxōn'', axis), or nerve fiber (or nerve fibre: see American and British English spelling differences#-re, -er, spelling differences), is a long, slender projection of a nerve cell, or neuron, in vertebrates, th ...

– projecting from the

cingulate gyrus The cingulate cortex is a part of the brain situated in the medial aspect of the cerebral cortex. The cingulate cortex includes the entire cingulate gyrus, which lies immediately above the corpus callosum, and the continuation of this in the ci ...

to the

entorhinal cortex The entorhinal cortex (EC) is an area of the brain's allocortex, located in the medial temporal lobe, whose functions include being a widespread network hub for memory, navigation, and the perception of time.Integrating time from experience in the ...

in the

brain A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a v ...

, allowing for communication between components of the

limbic system The limbic system, also known as the paleomammalian cortex, is a set of brain structures located on both sides of the thalamus, immediately beneath the medial temporal lobe of the cerebrum primarily in the forebrain.Schacter, Daniel L. 2012. ''Ps ...

. It forms the

white matter White matter refers to areas of the central nervous system (CNS) that are mainly made up of myelinated axons, also called tracts. Long thought to be passive tissue, white matter affects learning and brain functions, modulating the distribution ...

core of the cingulate gyrus, following it from the

subcallosal gyrus The subcallosal gyrus (paraterminal gyrus, peduncle of the corpus callosum) is a narrow lamina on the medial surface of the hemisphere in front of the lamina terminalis, behind the parolfactory area, and below the rostrum of the corpus callosum. I ...

of the

frontal lobe The frontal lobe is the largest of the four major lobes of the brain in mammals, and is located at the front of each cerebral hemisphere (in front of the parietal lobe and the temporal lobe). It is parted from the parietal lobe by a groove betwe ...

beneath the

rostrum of corpus callosum The corpus callosum (Latin for "tough body"), also callosal commissure, is a wide, thick nerve tract, consisting of a flat bundle of commissural fibers, beneath the cerebral cortex in the brain. The corpus callosum is only found in placental ma ...

to the

parahippocampal gyrus The parahippocampal gyrus (or hippocampal gyrus') is a grey matter cortical region of the brain that surrounds the hippocampus and is part of the limbic system. The region plays an important role in memory encoding and retrieval. It has been inv ...

and

uncus The uncus is an anterior extremity of the parahippocampal gyrus. It is separated from the apex of the temporal lobe by a slight fissure called the incisura temporalis (also called rhinal sulcus). Although superficially continuous with the hippo ...

of the

temporal lobe The temporal lobe is one of the four Lobes of the brain, major lobes of the cerebral cortex in the brain of mammals. The temporal lobe is located beneath the lateral fissure on both cerebral hemispheres of the mammalian brain. The temporal lobe ...

Neuron A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. N ...

s of the cingulum receive

afferent fibers Afferent nerve fibers are the axons (nerve fibers) carried by a sensory nerve that relay sensory information from sensory receptors to regions of the brain. Afferent projections ''arrive'' at a particular brain region. Efferent nerve fibers a ...

from the parts of the

thalamus The thalamus (from Greek θάλαμος, "chamber") is a large mass of gray matter located in the dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all directions, ...

that are associated with the

spinothalamic tract The spinothalamic tract is a part of the anterolateral system or the ventrolateral system, a sensory pathway to the thalamus. From the ventral posterolateral nucleus in the thalamus, sensory information is relayed upward to the somatosensory cor ...

. This, in addition to the fact that the cingulum is a central structure in learning to correct mistakes, indicates that the cingulum is involved in appraisal of pain and reinforcement of behavior that reduces it.

Cingulotomy Bilateral cingulotomy is a form of psychosurgery, introduced in 1948 as an alternative to lobotomy. Today, it is mainly used in the treatment of depression and obsessive-compulsive disorder. In the early years of the twenty-first century, it was ...

, the surgical severing of the anterior cingulum, is a form of

psychosurgery Psychosurgery, also called neurosurgery for mental disorder (NMD), is the neurosurgical treatment of mental disorder. Psychosurgery has always been a controversial medical field. The modern history of psychosurgery begins in the 1880s under th ...

used to treat depression and OCD. The cingulum was one of the earliest identified brain structures.

Anatomy and function

The cingulum is described from various brain images as a C shaped structure within the

that wraps around the

to the

right above the

corpus callosum The corpus callosum (Latin for "tough body"), also callosal commissure, is a wide, thick nerve tract, consisting of a flat bundle of commissural fibers, beneath the cerebral cortex in the brain. The corpus callosum is only found in placental mam ...

. It is located beneath the

within the medial surface of the brain therefore encircling the entire brain. There are two primary parts of the

cingulate cortex The cingulate cortex is a part of the brain situated in the medial aspect of the cerebral cortex. The cingulate cortex includes the entire cingulate gyrus, which lies immediately above the corpus callosum, and the continuation of this in the ci ...

: the

posterior cingulate cortex The posterior cingulate cortex (PCC) is the caudal part of the cingulate cortex, located posterior to the anterior cingulate cortex. This is the upper part of the "limbic lobe". The cingulate cortex is made up of an area around the midline of the ...

and the

anterior cingulate cortex In the human brain, the anterior cingulate cortex (ACC) is the frontal part of the cingulate cortex that resembles a "collar" surrounding the frontal part of the corpus callosum. It consists of Brodmann areas 24, 32, and 33. It is involved ...

. The anterior is linked to emotion, especially

apathy Apathy is a lack of feeling, emotion, interest, or concern about something. It is a state of indifference, or the suppression of emotions such as concern, excitement, motivation, or passion. An apathetic individual has an absence of intere ...

and depression. Here function and structure changes are related meaning any change within this structure would lead to a function change, particularly behavioral because of its function involving emotions. Damage to this area can have various effects on mental disorders and

mental health Mental health encompasses emotional, psychological, and social well-being, influencing cognition, perception, and behavior. It likewise determines how an individual handles stress, interpersonal relationships, and decision-making. Mental health ...

. The posterior section is more related to

cognitive Cognition refers to "the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception, attention, thought, ...

functions. This can include attention, visual and spatial skills,

working memory Working memory is a cognitive system with a limited capacity that can hold information temporarily. It is important for reasoning and the guidance of decision-making and behavior. Working memory is often used synonymously with short-term memory, ...

and general

memory Memory is the faculty of the mind by which data or information is encoded, stored, and retrieved when needed. It is the retention of information over time for the purpose of influencing future action. If past events could not be remembered, ...

. Because of its location, the cingulum is very important to brain structure connectivity and the integration of information that it receives.

Relation to cognitive impairment

In recent years the cingulum has been associated with various brain disorders and diseases. One such area of interest is the disruption of

in the posterior cingulum causing

mild cognitive impairment Mild cognitive impairment (MCI) is a neurocognitive disorder which involves cognitive impairments beyond those expected based on an individual's age and education but which are not significant enough to interfere with instrumental activities o ...

. Using diffusion

MRI Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves ...

techniques, researchers have associated mild cognitive impairment with damage to the cingulum. The cingulum is a frontal association tract that could play a critical role because it connects sites repeatedly implicated in cognitive control. The middle segment of the cingulum contains connections with premotor and motor cortical areas. Another place of importance that explains the cingulum and its relation to mild cognitive impairment is the fact that the cingulum connects to the

hippocampus The hippocampus (via Latin from Greek , 'seahorse') is a major component of the brain of humans and other vertebrates. Humans and other mammals have two hippocampi, one in each side of the brain. The hippocampus is part of the limbic system, a ...

. The cingulum takes memory information and integrates this to other parts of the brain. Damage to the cingulum also simultaneously damages the hippocampus. This is vital because the hippocampus is pivotal in memory storage. Damage to

gray matter Grey matter is a major component of the central nervous system, consisting of neuronal cell bodies, neuropil (dendrites and unmyelinated axons), glial cells (astrocytes and oligodendrocytes), synapses, and capillaries. Grey matter is distinguis ...

, bodies of neurons, or white matter of axons in the cingulum therefore can affect humans cognitively because of this damage. Also variations in microstructure of a group of fibers in the rostral cingulum have been shown to be extremely sensitive to performance of cognitive control tasks. White matter pathology of the cingulum represents one of the earliest changes in development of age-related dementia and is currently aiding researchers worldwide to discover more about this relationship.

Additional images

File:Hippocampal Limbic Connections Functions - Sanjoy Sanyal (Cropped from 4m03s to 4m57s) Cingulum.webm, Human brain dissection video (54 sec). Demonstrating the position of the cingulum. File:Tractography - Cingulum - animation 3.gif, One way to subdivide the cingulum. In this animation, the cingulum is divided into the five components. File:Different ways to subdivide the cingulum bundle.png, There are various ways to subdivide cingulum. From figure A to D, dividing the cingulum into 1, 2, 3, and 5 components respectively.

References

External links

Cingulate Gyrus: Introduction and Surface Morphology
{{Authority control Cerebrum Limbic system Articles containing video clips Central nervous system pathways de:Gyrus cinguli es:Giro cingulado nl:Gyrus cinguli pl:Zakręt obręczy pt:Giro do cíngulo sv:Limbiska systemet#Anatomi