How many lobes in the brain

The fluid is cerebrospinal fluid CSF , which also circulates over the outside of the brain and spinal cord. The brain stem is the part of the brain continuous with the spinal cord and comprising the medulla oblongata , pons, midbrain , and parts of the hypothalamus. The occipital lobe is the major visual processing centre in the brain.

The primary visual cortex , also known as V1, receives visual information from the eyes. This information is relayed to several secondary visual processing areas, which interpret depth, distance, location and the identity of seen objects. Help QBI research Give now. Skip to menu Skip to content Skip to footer. Site search Search. Site search Search Menu.

Lobes of the brain. Home The Brain Brain anatomy. Wikimedia Although we now know that most brain functions rely on many different regions across the entire brain working in conjunction, it is still true that each lobe carries out the bulk of certain functions. QBI Bumps and grooves of the brain In humans, the lobes of the brain are divided by a number of bumps and grooves.

Lesions of the anterior parietal lobe can cause difficulty recognizing objects by touch astereognosis. Areas posterolateral to the postcentral gyrus generate visual-spatial relationships and integrate these perceptions with other sensations to create awareness of trajectories of moving objects. These areas also mediate proprioception awareness of the position of body parts in space. Parts of the midparietal lobe of the dominant hemisphere are involved in abilities such as calculation, writing, left-right orientation, and finger recognition.

Lesions in the angular gyrus can cause deficits in writing, calculating, left-right disorientation, and finger-naming Gerstmann syndrome. The nondominant parietal lobe integrates the contralateral side of the body with its environment, enabling people to be aware of this environmental space, and is important for abilities such as drawing. Acute injury to the nondominant parietal lobe may cause neglect of the contralateral side usually the left , resulting in decreased awareness of that part of the body, its environment, and any associated injury to that side anosognosia.

For example, patients with large right parietal lesions may deny the existence of left-sided paralysis. Patients with smaller lesions may lose the ability to do learned motor tasks eg, dressing, other well-learned activities —a spatial-manual deficit called apraxia.

The temporal lobes are integral to auditory perception, receptive components of language, visual memory, declarative factual memory, and emotion. Patients with right temporal lobe lesions commonly lose the ability to interpret nonverbal auditory stimuli eg, music. Left temporal lobe lesions interfere greatly with the recognition, memory, and formation of language. Lesions in the primary visual cortex lead to a form of cortical blindness; in one form, called Anton syndrome, patients become unable to recognize objects by sight and are generally unaware of their deficits, often confabulating descriptions of what they see.

Seizures involving the occipital lobe can cause visual hallucinations, often consisting of lines or meshes of color superimposed on the contralateral visual field. The insula integrates sensory and autonomic information from the viscera. It plays a role in certain language functions, as evidenced by aphasia in patients with some insular lesions.

The insula processes aspects of pain and temperature sensation and possibly taste. The limbic lobe limbic system includes structures that receive inputs from diverse areas of the brain and that participate in complicated, interrelated behaviors eg, memory, learning, emotion.

Lesions that affect the limbic system usually result in a variety of deficits. Patients with epileptogenic foci in the medial limbic-emotional parts of the temporal lobe commonly have complex partial seizures, characterized by uncontrollable feelings and autonomic, cognitive, or emotional dysfunction. Occasionally, such patients have personality changes, characterized by humorlessness, philosophic religiosity, and obsessiveness.

Patients may have olfactory hallucinations and hypergraphia an overwhelming urge to write. Cerebral dysfunction may be focal or global. Focal and global processes can manifest as deficits or become foci for seizure activity. These processes may also affect subcortical systems, altering arousal eg, causing stupor or coma or integration of thought eg, causing delirium.

Structural abnormalities eg, tumors Overview of Intracranial Tumors Intracranial tumors may involve the brain or other structures eg, cranial nerves, meninges. The tumors usually develop during early or middle adulthood but may develop at any age; they are Symptoms may include headache, lethargy, fever, and focal neurologic deficits. Treatment is Diagnosis is suspected clinically and confirmed by imaging primarily Disorders that affect myelin interrupt nerve transmission Lesions that are 2 cm in diameter or that develop very slowly may be asymptomatic.

Larger lesions, rapidly developing lesions over weeks or months rather than years , and lesions that simultaneously affect both hemispheres are more likely to become symptomatic. Get the Shockwave plug-in. Lobes of the Brain The average human brain weighs about 1, grams 3 lb.

Concerned with reasoning, planning, parts of speech and movement motor cortex , emotions, and problem-solving. Concerned with perception of stimuli such as touch, pressure, temperature and pain.

Concerned with perception and recognition of auditory stimuli hearing and memory hippocampus. Concerned with many aspects of vision.