Search databaseBooksAll DatabasesAssemblyBiocollectionsBioProjectBioSampleBioSystemsBooksClinVarConserved DomainsdbGaPdbVarGeneGenomeGEO DataSetsGEO ProfilesGTRHomoloGeneIdentical Protein internet CatalogNucleotideOMIMPMCPopSetProteinProtein ClustersProtein household ModelsPubChem BioAssayPubChem CompoundPubChem SubstancePubMedSNPSRAStructureTaxonomyToolKitToolKitAllToolKitBookgh Bookshelf. A business of the national Library of Medicine, national Institutes that Health.

You are watching: The elevated ridges of the cerebrum are called

StatPearls . Endowment Island (FL): StatPearls Publishing; 2021 Jan-.



The nervous mechanism subdivides right into the central nervous system and also the peripheral nervous system. The central nervous system is the mind and spinal cord, if the peripheral nervous system is composed of every little thing else. The main nervous system"s responsibilities include receiving, processing, and also responding come sensory information.  

The brain is an organ of nervous tissue that is responsible for responses, sensation, movement, emotions, communication, believed processing, and memory. Protection for the human mind comes from the skull, meninges, and also cerebrospinal fluids. The nervous tissue is very delicate and can suffer damage by the the smallest amount the force. In addition, it has actually a blood-brain barrier preventing the mind from any type of harmful substance that might be floating in the blood.

The spinal cord is a an essential aspect that the CNS discovered within the vertebral column. The purpose of the spinal cord is come send motor commands from the mind to the peripheral body as well as to relay sensory info from the sensory organs to the brain. Spinal cord security is by bone, meninges, and also cerebrospinal fluids.

Structure and Function

The brain is broken up into two hemispheres, the left, and also the right. While they are in consistent communication, the left and right hemisphere space responsible for different behaviors, well-known as brain lateralization. The left hemisphere is more dominant v language, logic, and also math abilities. The best hemisphere is an ext creative, being leading in artistic and musical situations, and intuition. 

Cerebral cortex: The cerebral cortex is the outermost layer that surrounds the brain. The is composed of gray matter and also filled v billions of neurons supplied to conduct high-level executive, management functions. The cortex divides into 4 lobes; frontal, parietal, occipital, and also temporal by various sulci.<1> The frontal lobe, situated anteriorly to the main sulcus, is responsible for voluntary motor function, problem-solving, attention, memory, and language. Situated in the frontal lobe space the motor cortex and the Broca area. The motor cortex enables for the an accurate voluntary motions of ours skeletal muscles, while the Broca area controls motor features responsible for developing language. The parietal lobe is separated indigenous the occipital lobe by the parieto-occipital sulcus and is behind the central sulcus. That is responsible for handling sensory information and contains the somatosensory cortex. Neurons in the parietal lobe receive details from sensory and also proprioceptors throughout the body, procedure the can, and kind an understanding about what is gift touched based upon previous knowledge. The occipital lobe, recognized as the visual processing center, consists of the visual cortex. Comparable to the parietal lobe, the occipital lobe receives info from the retina and then provides past intuitive experiences come interpret and also recognize the stimuli. Lastly, the temporal lobe processes auditory stimuli with the hear cortex. Mechanoreceptors situated in the hair cell lining the cochlea are activated by sound energy, which subsequently sends impulses to the hear cortex. The advertise is processed and stored based upon previous experiences. The Wernicke area is in the temporal lobe and functions in speech comprehension. 

Basal nuclei: The basal nuclei, additionally known as basal ganglia, is located deep in ~ the cerebral white matter and also is created of the caudate nucleus, putamen, and globus pallidus. These structures kind the pallidum and also striatum. The basal ganglia are responsible because that muscle movements and also coordination.<2>

Thalamus: The thalamus is the relay facility of the brain. It receives afferent impulses from sensory receptors situated throughout the body and processes the info for circulation to the appropriate cortical area. The is additionally responsible because that regulating consciousness and sleep.

Hypothalamus: While the hypothalamus is one of the smallest components of the brain, that is vital to maintaining homeostasis. The hypothalamus connects the central nervous system to the endocrine system. The is responsible for heart rate, blood pressure, appetite, thirst, temperature, and also the release of miscellaneous hormones. The hypothalamus also communicates with the pituitary gland to release or inhibit antidiuretic hormone, corticotropin-releasing hormone, gonadotropin-releasing hormone, development hormone-releasing hormone, prolactin inhibiting hormone, thyroid releasing hormone, and also oxytocin.<3>

Pons: discovered in the brainstem, the pons connects the medulla oblongata and the thalamus. It is composed of tracts responsible for relaying impulses indigenous the motor cortex to the cerebellum, medulla, and also thalamus.

Medulla oblongata: The medulla oblongata is in ~ the bottom of the mind stem, where the spinal cord meets the foramen magnum that the skull. It is responsible for autonomic functions, few of which are an important for survival. The medulla oblongata monitors the body respiratory device using chemoreceptors. This receptors room able to detect transforms in blood chemistry. Because that example, if the blood is as well acidic, the medulla oblongata will boost the respiratory rate permitting for more oxygen to reach the blood.<4> the is additionally a cardiovascular and vasomotor center. The medulla oblongata can regulate the body"s blood pressure, pulse, and cardiac contractions based upon the body’s needs. Lastly, the controls reflexes prefer vomiting, swallowing, coughing, and sneezing.

Cerebellum: The cerebellum, likewise known as the small brain, is responsible for smooth, coordinated voluntary movements. The subdivides right into three lobes: the anterior, posterior, and also flocculonodular lobes. The cerebellum contains a cerebellar circuit, using Purkinje cells and cerebellar peduncles to connect to various other parts the the brain. The exceptional cerebellar peduncle is written of white issue that connect the cerebellum to the midbrain and enables for coordination in the arms and also legs. The inferior cerebellar peduncle associate the medulla and cerebellum making use of proprioceptors to preserve balance and posture. Lastly, the middle cerebellar peduncle is provided as a one-way communication technique from the pons come the cerebellum. The is greatly composed that afferent fibers the alert the cerebellum around voluntary motor actions. The cerebellum is in constant communication through the cerebral cortex, acquisition higher-level instructions around the brain’s intentions, processing them through the cerebellar cortex, then sending out messages come the cerebral motor cortex to do voluntary muscle contractions. This contractions room calculated to determine the force, direction, and momentum crucial to ensure every contraction is smooth and also coordinated.

Limbic System: The limbic system is composed of the piriform cortex, hippocampus, septal nuclei, amygdala, nucleus accumbens, hypothalamus, and also anterior nuclei that the thalamus.<5> The fornix and also fiber tracts connect the limbic device parts permitting them to control emotion, memory, and motivation. The piriform cortex is part of the olfactory system and is in the cortical area that the limbic system. The hypothalamus receives many of the limbic output, which describes psychosomatic illnesses, wherein emotional stressors reason somatic symptoms. For example, a patient who is currently having gaue won struggles might present to his primary care physician with hypertension and also tachycardia. The septal nuclei, amygdala, and also nucleus accumbens are uncovered in the subcortical areas and also are responsible because that pleasure, emotionally processing, and addiction, respectively.

Reticular formation: Reticular development is considerable network of pathways containing neurons that begins in the brainstem and also travels indigenous the optimal of the midbrain come the medulla oblongata. This pathways have actually projecting reticular neurons that affect the cerebral cortex, cerebellum, thalamus, hypothalamus, and also spinal cord. The reticular formation controls the body"s level that consciousness through the reticular activation system, likewise known together RAS. Sensory axons, discovered in visual, auditory, and also sensory impulses, activate RAS neurons in the brain stem. These neurons then relay info to the thalamus and cerebrum. Constant stimulation the the RAS neurons reasons the cerebrum to remain in an aroused state; this gives the feeling of alertness. However, RAS have the right to filter out repetitive, weak stimuli; this stays clear of the brain from responding come unimportant information, and also being sensory overloaded.

Spinal cord: The spinal cord proper extends native the foramen magnum of the skull come the first or 2nd lumbar vertebrae. It creates a two-way pathway in between the brain and the body and divides into 4 regions -  cervical, thoracic, lumbar, and also sacral. These areas are then damaged down into 31 segments v 31 bag of spinal nerves. There room 8 cervical nerves, 12 thoracic nerves, 5 lumbar nerves, 5 sacral nerves, and also 1 coccygeal nerve. Each nerve exit the vertebral tower passing through the intervertebral foramina and to that is designated ar in the body.

Due come cervical and also lumbar enlargements, the spinal cord differs in width throughout the structure. The cervical enlargement occurs at C3 come T1, and also the lumbar enlargement is in ~ L1 to S2. The white matter is current on the external of the spinal cord, through gray matter located in that is core and cerebrospinal liquid in the main canal. The gray commissure, the dorsal, lateral, and ventral horns space all composed of gray matter. The gray commissure surrounds the main canal. The dorsal horns are made that interneurons, when the ventral horns room somatic motor neurons. Afferent neurons in the dorsal roots carry impulses native the body’s sensory receptor to the spinal cord, where the information starts to it is in processed. The ventral horns contain efferent motor neurons, which regulate the body"s periphery. The axons of engine neurons are discovered in the body"s skeletal and also smooth muscle to manage both involuntary and also voluntary reflexes.   

The spinal cord end in a cone-shaped structure dubbed conus medullaris and also is supported to the finish of the coccyx by the filum terminale. Ligaments are uncovered throughout the spinal column, securing the spinal cord from optimal to bottom.

See more: What Is A Short E Sound : Sight Words For Junior Primary And Special Education

Ascending pathway to the brain: Sensory information travels native the human body to the spinal cord prior to reaching the brain. This information ascends upwards using first, second, and also third-order neurons. First-order neurons obtain impulses native skin and also proprioceptors and send them to the spinal cord. They climate synapse through second-order neurons. Second-order neurons live in the dorsal horn and send impulses come the thalamus and cerebellum. Lastly, third-order neurons choose up these impulses in the thalamus and also relay it come the somatosensory part of the cerebrum. Somatosensory sensations room pressure, pain, temperature, and also the body"s senses. 

Descending pathway: Descending tracts send engine signals from the brain to reduced motor neurons. These efferents neurons then produce muscle movement.<6>