The brain receives info through our 5 senses: sight, smell, touch, taste, and hearing – often several at one time. It assembles the messages in an exceedingly way that has which means for us and can store that info in our memory. The brain can control our thoughts, memory, speech, movement of the arms and legs, and also operate of many organs inside our body.

The central nervous system (CNS) comprises the brain and spinal cord. The peripheral nervous system (PNS) comprises spinal nerves that branch from the spinal cord and cranial nerves that branch from the brain.

Different Parts of the Brain

• Cerebellum: Anatomy, Location & Function
• Brain Stem: Anatomy, Location & Function
• Frontal Lobe: Anatomy, Location & Function
• Temporal Lobe: Anatomy, Location & Function
• Occipital Lobe: Anatomy, Location & Function
• Pons: Anatomy, Location & Function
• Medulla: Anatomy, Location & Function
• Cerebrum: Anatomy, Location & Function
• Spinal Cord: Anatomy, Location & Function

Deep structures of the Brain

Pathways called white matter tracts to connect areas of the cortex. Messages can proceed from one gyrus to another, from one lobe to another, from one side of the brain to the other, and structures deep in the brain.

• Thalamus: Anatomy, Location & Function
• Hypothalamus: Anatomy, Location & Function
• Pineal Gland: Anatomy, Location & Function
• Pituitary Gland: Parts, Location & Function
• Corpus Callosum: Anatomy, Location & Function
• Amygdala: Anatomy, Location & Function
• Basal ganglia: Anatomy, Location & Function
• Limbic system: Anatomy, Location & Function

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Purkinje fibers provide the heart’s conduction system to perform synchronized contractions of its ventricles, and are, consequently, necessary for keeping a steady heart rhythm. It is committed to a systematic rhythm of the heart. They extend from the interventricular septum, through the papillary muscles and laterally up the walls of the ventricles. A Czech anatomist and physiologist, who discovered the fibers in 1839.

Purkinje Fibers Histology

Purkinje fibers are networks of fibers that are a unique cardiac end-organ. Histologic examination exhibits that these fibers are split in ventricles walls. The electrical origin of atrial Purkinje fibers enters from the sinoatrial(SA) node. The Purkinje fibers are precisely shielded from each other by collagen or the cardiac skeleton.

The Purkinje fibers are different from the surrounding muscle cells because of comparatively fewer myofibrils than other cardiac cells and the carriage of glycogen throughout the nucleus, causes Purkinje fibers to appear, on a slide, lighter and bigger than their neighbors, arrayed along the longitudinal orientation (parallel to the cardiac vector). They are usually binucleated cells.

Purkinje Fibers Function

Purkinje fibers are an indispensable part of the functioning of the heart and are vital for our survival. They play a role of the relaying system of electrical signals in the heart, which manages the rate while the cardiac muscles contract and relax, or the rate at which the heart ‘beats’. Definitely, Purkinje fibers cause the ventricles, the lower two chambers of the heart, to create synchronized contractions of its ventricles.

The Purkinje fibers allow for a coordinated and controlled rhythm of blood circulation. Purkinje fibers comprise a distinct type of cardiac muscles that secure them the numerous efficient and quickest conductors of impulses in the cardiac system. The histology of Purkinje fibers reveals that they have thinner muscle tissues with fewer muscle strands than standard cardiac cells, which gives them appear lighter than different cells in a stained slide.

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Thalamus Anatomy

The thalamus a paired structure walnut-sized shaped of grey matter found in the forebrain that is superior to the midbrain, roughly the middle of the brain. The thalamus has four surfaces – Medial, lateral, superior and inferior surface and it has two ends or Poles -Anterior and posterior.

• Medial Surface: The medial surface of the thalamus forms the upper part of the lateral wall of the 3rd ventricle and is lined by ependyma. The medial surface is usually attached to the opposite thalamus by an interthalamic adhesion/bond. Inferiorly it is linked to the hypothalamus separated by an indistinct hypothalamic sulcus – this sulcus elongates from the upper end of cerebral aqueduct posteriorly to the interventricular foramen anteriorly. Through the junction of medial and superior surfaces, the ependyma of the third ventricle is revealed (from the lateral wall) to the roof. The line of reflection is indicated by a line designated taenia thalami, underlying which, there is a small bundle of fibers named stria medullaris thalami.
• Lateral Surface: The lateral surface of the thalamus is coated by a layer of myelinated fibers named external medullary lamina. The lamina divides lateral surface with the reticular nuclei.
• Superior surface: The superior surface of the thalamus is coated by a band of white matter designated stratum zonale.The medial part of this surface is separated from the overlying body of the fornix by the choroid fissure with the tela choroidea within it. More laterally it forms part of the floor of the lateral ventricle. The lateral border of the superior surface of the thalamus is signified by the stria terminalis and overlying thalamostriate vein, which divide the thalamus from the body of the caudate nucleus. Laterally, a slender sheet of white matter, the external medullary lamina, divides the main body of the thalamus from the reticular nucleus. Lateral to this, the thick posterior limb of the internal capsule occupies within the thalamus and the lentiform complex.
• Inferior Surface: The inferior surface of the thalamus is linked to the hypothalamus anteriorly and subthalamus posteriorly. The subthalamus divides thalamus from the midbrain tegmentum.
• Anterior end or Pole: It constitutes the posterior boundary of interventricular foramen.
• Posterior end or pole: Posterior end of the thalamus is designated as the Pulvinar. Pulvinar reaches beyond the third ventricle and overhangs the superior colliculus (Superior colliculus is a tiny elevation located on each side on the posterior aspect of the midbrain). Thus, pulvinar occupies just above and lateral to the superior colliculus. Subdivisions of Thalamus Inside, the thalamus is separated by a vertical Y-shaped of white matter, the internal medullary lamina within- Anterior nuclear groups Medial nuclear groups Lateral nuclear groups In extension, Intralaminar nuclei lie enclosed within and surrounded by, the internal medullary lamina. Reticular nuclei occupy laterally to the main nuclear mass, parted from it by the external medullary lamina. Midline nuclei either join the ependyma of the lateral walls of the third ventricle medially, or occupy adjacent to, and to some extent inside, the interthalamic adhesion. Medial and lateral geniculate bodies, previously regarded as Metathalamus, are now included as part of the Thalamus.

Connection of Thalamus The thalamus has multiple attachments to the hippocampus via the mammillothalamic tract, this tract holds the mammillary bodies and the fornix. The thalamus is linked to the cerebral cortex within the thalamocortical radiations.

The spinothalamic tract is a sensory pathway arising in the spinal cord. It sends information to the thalamus about temperature, pain, itch, and crude touch. There are two principal parts: the anterior (or ventral) spinothalamic tract, which carries crude touch and pressure and the lateral spinothalamic tract, which carries pain and temperature.

Thalamus Blood Supply

The thalamus receives its blood supply from plenty of arteries: paramedian thalamic-subthalamic arteries, the polar artery (posterior communicating artery), posterior (medial and lateral) choroidal arteries and inferolateral (thalamogeniculate) arteries. These are all derivatives of the posterior cerebral artery.

Thalamus Function

The thalamus is composed up of numerous collections of nerve cells that are centrally placed in the brain and are interconnected. Thalamus act as the relay station and integrate information into different subcortical areas of the brain and the cerebral cortex. There are thalamic nuclei concerning every sensory signal among the exception of the olfactory system. It takes sensory signals and sends them to the associated cortical area.

The medial geniculate nucleus of the thalamus transmits information connecting the inferior colliculus of the midbrain and the primary auditory cortex.

The lateral geniculate nucleus of the thalamus is associated with the visual system. It receives sensory inputs from the retina and acts rely upon station and process sensory information to the visual cortex. The medial geniculate nucleus acts as the relay station for the auditory system. The ventral posterior nucleus within the thalamus plays an important somatosensory relay that is liable for sending information relating to touch and proprioception to the primary somatosensory cortex.

Thalamus play a role in regulating sleep, wakefulness, and consciousness. The ventrolateral and the ventroanterior nuclei of the thalamus form part of the basal nuclei circuit and thus are committed in the performance of voluntary movements.

• Ventroanterior: It is concerned with the planning and initiation of movement.
• Ventrolateral: It is effective for the coordination and modulation of movement.
• Ventrointermedial: It supports coordinate different movements.

Thalamus Clinical Significance

The thalamic pain syndrome is caused by A cerebrovascular accident (stroke), which involves a one-sided burning or aching sensation often characterized by mood swings. Bilateral ischemia of the thalamus is supplied by the paramedian artery can produce serious difficulties including akinetic mutism, and be characterized by oculomotor problems. The occlusion of the Percheron artery can commence to a bilateral thalamus infarction.

Fatal familial insomnia is an inherited prion condition that is caused by the degeneration of thalamus, producing the patient to progressively lose his ability to sleep and advancing to a state of total insomnia, which habitually commences to death. In contrast, injury to the thalamus can occur in the coma.

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Cerebellum Location

The cerebellum is positioned at the posterior part of the brain, directly under the occipital and temporal lobes, and inside the posterior cranial fossa. It is isolated from those lobes through the tentorium cerebelli, a tough layer of dura mater.

The cerebellum prevails at the alike level and posterior to the pons, from which it is divided by the fourth ventricle.

Cerebellum Anatomy

The cerebellum is divided into two hemispheres.which are connected by the vermis, a narrow midline area. Similar to the other structures of the central nervous system, the cerebellum consists of grey matter and white matter:
Grey matter found on the surface of the cerebellum. It is tightly folded, making the cerebellar cortex.
White matter found under the cerebellar cortex. Set in the white matter are the four cerebellar nuclei (emboliform, the dentate, globose, and fastigi nuclei).

The cerebellum comprises innumerable neurons than the total from the rest of the brain but takes up just 10% of the total brain volume. The number of neurons in the cerebellum is linked to the number of neurons in the neocortex. There are approximately 3.6 times as many neurons in the cerebellum as in the neocortex.
Anatomical Lobes of the cerebellum
There are three anatomical lobes in the cerebellum; the anterior lobe, the posterior lobe and the flocculonodular lobe. These lobes divide the cerebellum from rostral to caudal. These lobes are separated by the primary fissure and posterolateral fissure. The flocculonodular lobe is often called the vestibulocerebellum.

Zones of the cerebellum
There are three cerebellar zones. In the midline of the cerebellum is the vermis. Each side of the vermis is the intermediate zone. Lateral to the intermediate zone holds the lateral hemispheres. There is no variation in gross structure among the lateral hemispheres and the intermediate zones

Functional Divisions of the cerebellum
The three functional areas of the cerebellum – the cerebrocerebellum, the spinocerebellum and the vestibulocerebellum.

• Cerebrocerebellum – the largest division of the cerebellum, made by the lateral hemispheres. Cerebrocerebellum is involved in planning movements and motor learning. It takes inputs from the cerebral cortex and pontine nuclei and transmits outputs to the thalamus and red nucleus. The Cerebrocerebellum area also regulates coordination of muscle activation and is essential in visually guided movements.
• Vestibulocerebellum – the functional equivalent to the flocculonodular lobe. Vestibulocerebellum is concerned with controlling balance and ocular reflexes, principally fixation on a target. It gets inputs from the vestibular system and transmits outputs back to the vestibular nuclei.
• Spinocerebellum – including the vermis and intermediate zone of the cerebellar hemispheres. It is implicated in regulating body movements by supporting error correction. It additionally receives proprioceptive information.

Blood Supply of the cerebellum

The cerebellum takes blood supply from three paired arteries:

• Superior cerebellar artery (SCA)
• Anterior inferior cerebellar artery (AICA)
  The SCA and AICA are branches of the basilar artery,
• Posterior inferior cerebellar artery (PICA)
  The PICA is a branch of the vertebral artery.

Venous drainage by the superior and inferior cerebellar veins. They drain toward the superior petrosal, transverse, and straight dural venous sinuses.

Cerebellum Function

The cerebellum gets information from the sensory systems, the spinal cord, and other components of the brain and later coordinates motor movements. While the cerebellum is not considered initiating movement, but it regulates such as posture, coordination, balance, and speech, resulting in a smooth and well-balanced muscular activity.

The cerebellum plays a significant role in this motor learning behavior.

Cerebellar Disorder

Damage to the cerebellum, while not producing paralysis or intellectual impairment, might commence to a lack of balance, tremors (shaking) and slower movements. Complex physical tasks would become unsteady and halting.

Patients with cerebellar disturbance from a variety of abnormal eye movements occur.

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The brain stem performs the motor and sensory innervation to the face and neck through the cranial nerves. Regarding the twelve pairs of cranial nerves, the ten pairs come from the brainstem. This is an extremely valuable part of the brain as the nerve connections of the motor and sensory systems from the central part of the brain to the rest of the body reach through the brainstem. This comprises the corticospinal tract (motor), the dorsal column-medial lemniscus pathway ( vibration sensation, fine touch, and proprioception), including the spinothalamic tract ( temperature, pain, itch, and crude touch).

The brainstem further performs an important role in the regulation of cardiac and respiratory function. The brainstem additionally regulates the central nervous system and is crucial in maintaining consciousness and controlling the sleep cycle. The brainstem provides multiple fundamental functions including heart rate, breathing, sleeping, and eating.

Brain Stem Parts

Midbrain: Midbrain also called mesencephalon, that is composed of the tectum, tegmentum, and the ventral tegmentum. The midbrain serves important functions in motor movement, particularly movements of the eye, and in auditory and visual processing. It is positioned within the brainstem and between the forebrain, and the hindbrain. The midbrain is the tiniest of the three areas of the brainstem, averaging around 2cm in length.

The tectum comprises the inferior and superior colliculi and dorsal covering of the cerebral aqueduct. The inferior colliculus is the main midbrain nucleus concerning the auditory pathway and gets input from several peripheral brainstem nuclei, as thoroughly as inputs from the auditory cortex. Superior to the inferior colliculus, the superior colliculus signifies the rostral midbrain. The superior colliculus is committed in the special sense of vision and transmits its superior brachium to the lateral geniculate body of the diencephalon. The tegmentum of the brain stem which makes the floor of the midbrain and this part is ventral to the cerebral aqueduct. Numerous nuclei, tracts, and the reticular formation are carried here. The ventral tegmentum is included in paired cerebral peduncles. These transmit axons of upper motor neurons.

Pons: The pons is the part of a brainstem and lies inferior to the midbrain, superior to the medulla oblongata and anterior to the cerebellum. This the region of the brainstem comprises neural pathways and tracts that transfer signals from the brain down to the cerebellum and medulla and tracts that transmit the sensory signals up into the thalamus.
The pons measures about 2.5 centimeters (0.98 in) in length in humans. Most of it resembles a wide anterior bulge rostral to the medulla. Posteriorly, pons consists chiefly of two pairs of thick stalks designated the cerebellar peduncles. They attach the cerebellum to the pons and the midbrain.
The pons comprises nuclei that transmit signals from the forebrain to the cerebellum, accompanying with nuclei that deal principally with sleep, respiration, swallowing, bladder control, hearing, taste, equilibrium, eye movement, facial expressions, facial sensation, and posture.
Inside the pons is the pneumotaxic center consisting of the subparabrachial and the medial parabrachial nuclei. This center controls the change from inhalation to exhalation.
The pons is connected to sleep paralysis, and may likewise play a role in generating dream.

Medula: The medulla also has known as the medulla oblongata is placed in the brainstem, anterior and somewhat lower to the cerebellum. The medulla is a cone-shaped neuronal mass adapted for autonomic functions ranging from vomiting to sneezing. The medulla oblongata comprises the cardiac, respiratory, vomiting and vasomotor centers and consequently deals with the autonomic functions of breathing, heart rate, and blood pressure.
Throughout embryonic development, the medulla oblongata develops from the myelencephalon. The myelencephalon is a secondary vesicle which makes during the maturation of the rhombencephalon, likewise suggested to as the hindbrain.
The bulb is an archaic term for the medulla oblongata, can refer to the nerves and tracts attached to the medulla, and also by association with those muscles innervated, such as the tongue, pharynx, and larynx.

Brain Stem Function

There are three main functions of the brainstem:
The brainstem performs a function in conduction. All information transferred from the body to the cerebrum and cerebellum and vice versa must traverse the brainstem. The ascending pathways becoming from the body to the brain are the sensory pathways and include the spinothalamic tract for pain and temperature sensation and the cuneate fasciculus for touch, proprioception, and the dorsal column-medial lemniscus pathway including the gracile fasciculus pressure sensation.

The cranial nerves III-XII emerge from the brainstem. These cranial nerves supply the head, face, and viscera. The first two pairs of cranial nerves originate from the cerebrum.
The brainstem functions being involved in respiratory control, cardiovascular system control, pain sensitivity control, alertness, awareness, and consciousness. The brain stem damage is really serious and usually life-threatening problem.

In a summation, the brainstem controls numerous important functions of the body including:

• Breathing
• Blood Pressure Control
• Alertness
• Arousal
• Digestion
• Heart Rate
• Additional Autonomic Functions

The brain stem carries information among the peripheral nerves and spinal cord to the upper portions of the brain.

Brain Stem Injury

Brainstem injury caused by trauma or stroke can commence to troubles with mobility and movement coordination, such as walking, writing, and eating become difficult and the individual may need life-long treatment. Stroke that happens in the brainstem causes the destruction of brain tissue that is needed for the direction of vital body roles such as respiration, heart rhythm, and swallowing. A stroke transpires while blood flow to the brain is disrupted, most usually by a blood clot. While the brainstem is damaged, signals among the brain and the rest of body are interrupted.

• Brainstem stroke can cause breathing, heart rate, hearing, and speech problem. It may further induce paralysis of the arms and legs, as thoroughly as dullness in the body or on one side of the body.
• Brain stem stroke can further cause double vision, slurred speech and diminished the level of consciousness.

Risk factors for brain stem stroke are high blood pressure, diabetes, heart disease, atrial fibrillation, and smoking.

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Pineal Gland Anatomy

The pineal gland is a pine-cone shape located midline the brain structure that is unpaired and lies between the laterally positioned thalamic bodies and behind the habenular commissure. The pineal gland is placed in the quadrigeminal cistern adjacent to the corpora quadrigemina. It is also found behind the third ventricle and is immersed in cerebrospinal fluid supplied within a small pineal recess of the third ventricle which projects into the stalk of the gland.
The pineal gland is reddish-gray and regarding the size of a grain of rice (5–8 mm) in humans brain.

Blood Supply of the Pineal Gland
The pineal gland is not separated from the body by the blood-brain barrier system, it becomes profuse blood flow, satisfied from the choroidal branches of the posterior cerebral artery.
Nerve supply of the Pineal Gland
The pineal gland gets a sympathetic innervation from the superior cervical ganglion and the parasympathetic innervation from the pterygopalatine and otic ganglia. Some nerve fibers enter into the pineal gland via the pineal stalk. Moreover, neurons in the trigeminal ganglion innervate the gland among nerve fibers containing the neuropeptide PACAP.

Pineal Gland Function

The principal function of the pineal gland is to generate melatonin. Melatonin has numerous functions in the central nervous system, the various important of which is to help accentuate sleep patterns. Melatonin formation is aroused by darkness and repressed by light. Light-sensitive nerve cells in the retina recognize light and transmit this signal to the suprachiasmatic nucleus (SCN), synchronizing the SCN to the day-night cycle.
Regulation of the pituitary gland
The pineal gland regulates the pituitary gland’s secretion of the sex hormones, luteinizing hormone (LH) and follicle-stimulating hormone (FSH).
Drug Metabolism
The pineal gland may influence the actions of recreational drugs, such as cocaine, and antidepressants, such as fluoxetine, that its hormone melatonin can protect against neurodegeneration.
Bone Metabolism
The pineal-derived melatonin which regulates new bone deposition. Pineal-derived melatonin interferes with its action on the bone cells through MT2 receptors. This pathway could be a possible new target for osteoporosis remedy as the study shows the curative effect of oral melatonin treatment in a postmenopausal osteoporosis mouse model.
Stabilization of Mood
The size of the pineal gland may show the jeopardy for certain mood disorders. One research implies that a moderate pineal gland volume may raise the chance of evolving schizophrenia and other mood complications.
Cancer & Pineal Gland
Some study implies that there may be a link among impaired pineal gland function and cancer risk. A recent study on rats showed the indication that lowering pineal gland function through overexposure to light led to cellular degeneration and raised risk for colon cancer.
Cardiovascular Health & Pineal Gland
Studies discovered proof that melatonin generated by the pineal gland can enhance a positive influence on the heart and the blood pressure. They assumed that melatonin may be utilized to treat cardiovascular disease, though more research is required.
Female Hormones & Pineal Gland
In the case of the female hormone, there’s some evidence that reduced amounts of melatonin may perform a role in the development of irregular menstrual cycles.

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Pituitary Gland Function

The hormones of the pituitary gland transmit signals to another endocrine gland to excite or repress their own hormone production. For instance, the anterior pituitary lobe of the pituitary gland will release adrenocorticotropic hormone (ACTH) to stimulate cortisol production in the adrenal glands during you’re stressed.

Anterior Lobe Hormones & Function: The anterior lobe releases hormones upon receiving releasing or inhibiting hormones from the hypothalamus, whether to release more of a specific hormone or stop production of the hormone.

Follicle-stimulating hormone (FSH): Follicle-stimulating hormone accomplishes with Luteinizing hormone to secure normal functioning of the ovaries and testes.

Adrenocorticotropic hormone (ACTH): Adrenocorticotropic hormone stimulates the adrenal glands to produce hormones.

Growth hormone (GH): Growth hormone is necessary for early years to maintaining a healthy body composition and for growth in children. In adults, it supports healthy bone and muscle mass and affects fat distribution.

Thyroid-stimulating hormone (TSH): Thyroid-stimulating hormone stimulates the thyroid gland to produce hormones.

Luteinizing hormone (LH): Luteinizing hormone accomplishes with Follicle-stimulating hormone to secure normal functioning of the ovaries and testes.

Prolactin: Prolactin hormone stimulates the breast milk production.

Intermediate Lobe Hormones & Function: The intermediate lobe synthesizes and secrets –

Melanocyte-stimulating hormone (MSH). This is further produced in the anterior lobe. While Melanocyte-stimulating hormone produced in the intermediate lobe, MSHs are sometimes termed “intermedins”.

Posterior Lobe Hormones & Function: The posterior lobe comprises the ends of nerve cells originating from the hypothalamus. The hypothalamus transmits hormones directly to the posterior lobe through those nerves, and then the pituitary gland releases a specific hormone or stops production of the hormone.

Oxytocin: Oxytocin is involved in contracting the uterus throughout childbirth and stimulating breast milk production.

Anti-diuretic hormone (ADH): The Anti-diuretic hormone arouses the kidneys to enhance water absorption in the blood.

Pituitary Gland Diseases and Disorders

Some of the diseases involving the pituitary gland are:

• Gigantism and acromegaly induced by an overload of growth hormone in childhood and adult individually.
• Central diabetes insipidus induced by an insufficiency of vasopressin.
• Hypothyroidism generated by an insufficiency of thyroid-stimulating hormone.
• Hypopituitarism, the lowered secretion of one or more of the hormones, produced by the pituitary gland.
• Hyperpituitarism, the increased secretion of one or more of the hormones normally produced by the pituitary gland.
• Panhypopituitarism a modified secretion of most of the pituitary hormones.
• Pituitary adenomas, noncancerous tumors that transpire in the pituitary gland.
• Pituitary tumors.

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The precentral gyrus, a part of the frontal lobe immediately anterior to the central sulcus, holds the primary motor cortex, that controls voluntary actions of particular body parts.

The frontal lobe comprises the maximum of the dopamine-sensitive neurons in the cerebral cortex. The dopaminergic system is linked with reward, attention, short-term memory tasks, planning, and motivation. Dopamine serves to limit and pick sensory information reaching from the thalamus to the forebrain.

Frontal Lobe Anatomy

The frontal lobe can be divided into a lateral, polar, orbital) and medial part. Each of these sections consists of a particular gyrus: On the lateral surface of the brain, the central sulcus divides the frontal lobe from the parietal lobe. The lateral sulcus divides the frontal lobe from the temporal lobe.

The lateral part contains the superior frontal gyrus, middle frontal gyrus, inferior frontal gyrus.

Polar part contains the transverse frontopolar gyri, frontomarginal gyrus.

The orbital part contains orbital gyrus, anterior orbital gyrus, posterior orbital gyrus, medial orbital gyrus, gyrus rectus.

The medial part contains superior frontal gyrus, cingulate gyrus.

The gyri are divided by the sulci. The precentral gyrus is in front of the central sulcus and backward the precentral sulcus. The superior and middle frontal gyri are separated by the superior frontal sulcus. The middle and inferior frontal gyri are separated by the inferior frontal sulcus.

Frontal Lobe Location

The frontal lobe is located toward the front of the cerebrum, just back the forehead and below the frontal skull bones. It rests atop the temporal lobe, in front of the parietal lobe, and separated from the occipital lobe, with pieces of the limbic system. The limbic system is sometimes called the limbic lobe, that crossing all four brain lobes, including the frontal lobe.

The central sulcus divides the frontal and parietal lobes, with the lateral sulcus dividing the frontal and temporal lobes.

Frontal Lobe Function

The frontal lobe performs a comprehensive role in the voluntary movement. The frontal lobe is home to the primary motor cortex which regulates activities like walking.

The role of the frontal lobe comprises the ability to project future outcomes occurring from current actions, the choice among good and bad actions, the override and elimination of socially unacceptable responses, and the perception of similarities and differences among things or events. Thus the frontal lobe plays an essential role in impulse control, including decisions regarding while to spend money and eat, and whether a selective decision is morally or socially acceptable.

The frontal lobe further plays a significant part in integrating longer non-task based memories stored across the brain. Creation and preservation of long-term memories, especially emotional memories derived from the limbic system. The frontal lobe transforms those emotions to generally fit socially acceptable norms.

Dopamine, a neurotransmitter that performs a role in reward and motivation, is profoundly active in the frontal lobe because of most of the brain’s dopamine-sensitive neurons found here.

Psychological tests that measure frontal lobe function include finger tapping the Wisconsin Card Sorting Test and tests of language and numeracy skills.

The frontal lobe performs a role in understanding language, semantic memories, and speaking.

Frontal Lobe Damage

The frontal lobe damage can occur in several ways and result in different results. Transient ischemic attacks are also known as mini-strokes, and stroke is a common conditions of frontal lobe damage in older adults after 65 and over. These strokes and mini-strokes can happen due to the blockage of blood flow to the brain or as a result of the bursting of an aneurysm in a cerebral artery. Other processes, in which damage can occur include head injuries such as traumatic brain injuries contracted following accidents,  frontal lobe epilepsy that can occur at any age and Alzheimer’s disease or Parkinson’s disease that causes dementia symptoms.

Some other consequences of frontal lobe damage include:

• Problems with planning, executive functioning, and attention.
• Lack of memory.
• Incompetence to engage in immoral decision-making.
• Sudden and dramatic differences in personality.
• Variations in emotions, including signs of depression and anxiety.
• The trouble with understanding social cues or relating to the emotions of other people.
• Declining intelligence.
• Fluctuations in motor skills and spatial thinking abilities.

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Temporal lobe Anatomy

The temporal lobe consists of edifices that are essential for declarative or long-term memory. Declarative or explicit memory is understanding memory classified into semantic memory (facts) and episodic memory (events). The temporal lobe is important for long-term memory to involve the hippocampus, accompanying the surrounding hippocampal region consisting of the perirhinal, parahippocampal, and the entorhinal neocortical regions. The hippocampus is significant for memory formation, and the encompassing medial temporal cortex is currently theorized to be significant for memory storage. The prefrontal and visual cortices are similarly committed in explicit memory.

Experimentation has revealed that lesions in the hippocampus of monkeys produce in limited impairment of function, whereas extended lesions that involve the hippocampus and the medial temporal cortex result in drastic impairment.

The limbic lobe of the brain truly converges with several lobes but combines directly with the temporal lobe to control the limbic system, including automatic emotional responses such as the fight-or-flight response. The limbic lobe is addressing key memory, learning, and attention processing structures such as the amygdala and the hippocampus. This brain area further manages a number of automatic, unconscious biological functions, as considerably as unconscious emotional states, such as the sexual arousal and the appetite.

Wernicke’s area is associated with the judgment and the processing of speech.

Broca’s area helps in the production of speech, though amazing evidence suggests that, while Broca’s area is damaged, nearby areas may compensate. Coincidentally with Wernicke’s area, Broca’s area assists communication.

Temporal lobe Location-The temporal lobe is positioned toward the base of the center of the cortex, just behind the temples. Though every temporal lobe has an alike structure, the experiences presented in each person’s temporal lobe are uniquely their individual.

Temporal Lobe Function

The temporal lobe performs an important role in auditory processing. This function includes understanding sounds, empowering meaning to those sounds, and recalling sounds. Paramount of the auditory functioning of the temporal lobe is processed within the superior temporal gyrus, a temporal lobe arrangement that takes sound input quickly from the ear. Remarkable of its additional functions comprise:

The generation of visual memories, including long-term memories. In combination with the amygdala and hippocampus, the temporal lobe is important for the formation of conscious memories.

Understanding the meaning of visual stimuli, including identifying objects. It’s not acceptable to just see an object. For vision to be beneficial, you must further understand whatever it is you are seeing. The ventral portion of the temporal lobe aids in the responsibility of meaning to the visions you take in every day. Outwardly the ventral lobe, you would not be capable of identifying faces or reading body language.

Production of speech- Dysfunction in this brain region can commence to difficulties speaking, even when different structures are intact or you can consciously imagine what you want to say.

Recognition of language-The auditory cortex within the temporal lobe is important for hearing and judgment speech, but a range of other arrangements in the temporal lobe improve your understand and give meaning to language. If the temporal lobe damaged, you could not remember verbal exchanges or recognize the language.

Regulating unconscious and seemingly automatic reactions, before-mentioned as appetite, thirst, hunger.

Temporal lobe maintaining body control homeostasis. This important role is shared by many regions of the brain.

Temporal Lobe Damage

The effects of temporal lobe damage are myriad, and can include:

• Temporal lobe epilepsy cause seizures that produce uncontrolled electrical activity in the brain that can lead to seizures.
• Damage to Broca’s region does prevent the ability to speak, while injury to Wernicke’s area can prevent the ability to understand speech.
• Impaired memory skills depend on the location of the damage, but common problems involve difficulty recognizing people, faces, or objects; inadequate long-term memory; disorders in autobiographical memory, and weak auditory memory.

• Changes in personality regarding emotional regulation and interpersonal communications.
• Changes in self-regulating behaviors, such as hunger, thirst, appetite, and sexual desire.
• Changes in spatial navigation and spatial reasoning. People with temporal lobe damage may encounter challenges driving, paying attention to physical directions, or navigating their way around the world.

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The parietal lobe integrates sensory information with numerous modalities, including spatial sense and proprioception, the main sensory receptive region for the sense of touch in the somatosensory cortex, that is exactly posterior to the central sulcus and the dorsal stream of the visual system. The major sensory inputs from the skin such as temperature, touch and pain receptors relay throughout the thalamus to the parietal lobe.

Numerous areas of the parietal lobe are necessary for language processing. The superior and inferior parietal lobule are the primary areas of the body or spacial awareness. A lesion usually in the right superior or inferior parietal lobule commences to hemineglect.

Parietal Lobe Anatomy

The parietal lobe is described by the three anatomical landmarks: The central sulcus divides the parietal lobe from the frontal lobe; the parieto-occipital sulcus divides the parietal and occipital lobes; the lateral sulcus is the most lateral boundary, dividing it from the temporal lobe. The medial longitudinal fissure separates the two hemispheres. Inside each hemisphere, the somatosensory cortex serves the skin area on the contralateral surface of the body.

Being divided into the left and right hemisphere, some definite structures playing important roles in brain functioning. These comprise the following:

Posterior Parietal Cortex coordinates movements and spatial reasoning play a vital role in attention to the new stimulus.

Postcentral Gyrus area is the primary somatosensory cortex, which obtains sensory information and loads it on a sensory homunculus. This area is also designated to as Brodmann Area 3.

Inferior Parietal Lobule is capable of assessing facial expressions to judge emotions. It also assists in processing language, mathematical operations, and body language.

Superior Parietal Lobule assists in the determination of one’s own spacial orientation as well as of different objects such as addresses and roads. It gains significant input by hand, that is, it supports the coordination of fine motor skills.

Primary Sensory Area where the impulse from the skin is obtained and interpreted, such as cold, warmth, touch, and pain.

The parietal lobe is known for sensory perception and integration, including the taste, hearing, sight, touch, and smell. The parietal lobe is home to the brain’s primary sensory area, an area where the brain interprets input from other areas of the body.

Parietal Lobe Function

Differentiating between two points, even outwardly visual input.

Graphesthesia – recognizing the writing on the skin by touch alone.

Localizing touch: During you touch an object with any part of your body, your parietal lobe empowers you to feel the sensation at the site of the touch.

Integrating sensory information from maximum areas of the body.

Visuospatial navigation and reasoning-during you see a map, follow directions or check yourself from tripping over an unexpected obstacle, your parietal lobe is concerned. The parietal lobe is also necessary for proprioception—the ability to determine where your body is in space, including in relation to itself. For example, touching your finger to your nose without the assistance of a mirror is a function of the parietal lobe.

• Assessing numerical relationships, including the number of objects you see.
• Some visual functions, in conjunction with the occipital lobe.
• Assessing shape, size, and orientation in space of both visible stimuli and objects you remember encountering.
• Mapping the visual world-specific regions in the parietal lobe serves as maps to the visual world.
• Coordinating hand, arm, and eye motions.
• Coordinating attention.
• Processing language.

Parietal Lobe Damage

The parietal lobe damage can lead to irreversible consequences. The prognosis depends on the site of damage, how severe the injury is and if treatment is possible or not. The care may include occupational, speech and physical therapy. Individual diagnosis and treatment support other regions of the brain to compensate. The 3 specific syndromes commonly found in patients fighting parietal lobe damage.

Gerstmann’s Syndrome is a collection of symptoms that occur as a result of a damaged parietal lobe prevailing in the left hemisphere. The patient is marked struggling with writing, arithmetics, language, perception logics.

Balint’s Syndrome has occurred on both sides of the parietal lobes. It diminishes motor skills simultaneously with visual attention. Voluntary eye movements may grow weak in the patient. These type of patients is not able to integrate all the attributes of a visual picture and may similarly be inadequate to manipulate an object in the inadequacy of a visual stimulus.

If the right parietal lobe damaged, the strength to care for one’s own body is diminished as the patient is incapable to notice for at least one side of the body. The ability to draw is similarly diminished.

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Injury to the occipital lobe can induce visual difficulties such as trouble with recognizing objects, an inadequacy to identify colors, and difficulty recognizing words.

Occipital Lobe Anatomy

The two occipital lobes are the tiniest of four paired lobes in the cerebral cortex. The occipital lobes are positioned in the rearmost portion of the skull, the occipital lobes are part of the forebrain. The occipital lobe is marked as the component of the cerebral cortex that lies underneath the occipital bone.
The lobes of the occipital rest on the tentorium cerebelli, a part of dura mater that divides the cerebrum from the cerebellum. They are structurally separated in their respective cerebral territories by the separation of the cerebral fissure. At the front edge of occipital lobes are numerous lateral occipital gyri, which are divided by the lateral occipital sulcus.
The occipital viewpoints along the inner face of each hemisphere are separated by the calcarine sulcus. Beyond the medial, Y-shaped sulcus rests the cuneus, and the place under the sulcus is the lingual gyrus.

Occipital Lobe Location: Bottom, back part of the cortex.

Occipital Lobe Function

The occipital lobe is a visual processing station of the individual mammalian brain comprising most of the anatomical area of the visual cortex. The second cranial nerve is the optic nerve, fibers arise from the retina to make the optic nerve. Thalamic fibers run to the occipital cortex, where visual interpretation happens.
• Its primary occipital lobe function is processing, integration, interpretation, vision and visual stimuli.
• The primary visual cortex is the primary area of the brain capacity for the sight recognition of size, motion, color, dimension, etc.
• Controls visual perception is also a chief occipital lobe function.

Occipital Lobe Clinical Significance

If one occipital lobe is injured, the outcome can be homonymous hemianopsia vision loss from similarly put “field cuts” in each eye. Occipital lesions can induce visual hallucinations. Lesions in the parietal-temporal-occipital are correlated with movement agnosia, color agnosia, and agraphia. Injury to the primary visual cortex can create blindness due to the holes in the visual projection on the surface of the visual cortex that occurred from the lesions.

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Pons Anatomy

Internal Anatomy

The pons is composed of two significant segments – ventral pons and the tegmentum.
The ventral pons comprises the pontine nuclei, which are capable of coordinating movement. Fibers of the pontine nuclei cross the midline and develop the middle cerebellar peduncles on their move to the cerebellum.
The tegmentum part of the pons which forms a set of nuclei found throughout the brainstem that are liable for arousal and attentiveness. Injury to this part of the pons may happen in anosognosia for hemiplegia, where victims are ignorant of their paralysis.

The pons is made up of tracts crossing through the pons, comprises:
Descending corticobulbar tracts – responsible for voluntary motor control of face, head, and neck.
Descending corticospinal tracts – responsible for voluntary motor control of the body.
Ascending spinothalamic tracts – responsible for pain and temperature sensation.
Ascending medial lemniscus tracts – responsible for fine touch, vibration, and proprioception.

Anterior Surface

The anterior surface of the pons is a bulging formed by the transverse pontocerebellar fibers.
The basilar groove separates the midline of the anterior surface and is where the basilar artery is positioned.
Numerous cranial nerves arise from the anterior surface of the pons:
Cranial nerve VIII: vestibulocochlear – arises laterally to the facial nerve.
Cranial nerve VII: facial – arises from the cerebellopontine angle, the more lateral aspect of the pontomedullary junction.
Cranial nerve VI: abducens – arises from the pontomedullary junction, close to the midline.
Cranial nerve V: trigeminal – arises from the lateral aspect of mid pons.

Posterior Surface

The floor of the fourth ventricle is comprised of the posterior surface of the pons and the medulla. There are some significant anatomical marks here:
The facial colliculus of pons is a bulging formed fiber of the facial nerve connecting throughout the abducens nucleus.
The medial eminence signifies the midline of the floor.
The stria medullaris is a bundle of nerve fibers crisscrossing transversely of the lateral aspect into the midline. They identify the posterior border within the pons and the medulla.

The angle formed at the junction of the pons, cerebellum, and medulla, is another anatomical landmark and is identified at the cerebellopontine angle. Here, the ventricular choroid plexus, cerebellar flocculus, and emerging CNs VII and VIII enclose the lateral apertures the foramen of Luschka, of the fourth ventricle.

Pons Blood Supply

The blood supply of the pons is by branches regarding the vertebrobasilar system:
Maximum of the pons is fulfilled by the pontine arteries, parts of the basilar artery
A tinier part of its blood supply becomes from an anterior inferior cerebellar artery and the superior cerebral artery.

Vein‎: ‎Transverse and lateral pontine veins

Pons Function

The functions of the pons include sensory roles in the hearing, equilibrium, taste, facial sensations such as touch and pain, roles in eye movement, chewing, facial expressions, swallowing, and the discharge of saliva and tears.

Pons Clinical Significance

Center pontine myelinolysis is a demyelination condition that makes difficulty with a sense of balance, swallowing, walking, a sense of touch, and speaking.

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