The cerebrum , the largest region of the brain, contains motor, sensory and association areas

Three points about the cerebral lobes

1. Each cerebral hemisphere receives sensory information from and sends motor commands to, the opposite side of the body 2. The two hemispheres have different functions, even though they look almost identical 3. The correspondence between a specific function and a specific region of the cerebral cortex is imprecise

Temporal lobe

A region of the cerebral cortex responsible for hearing and language. Auditory association area Auditory cortex - hearing Olfactory cortex - smell

Occipital Lobe

A region of the cerebral cortex that processes visual information Visual association area Visual cortex

Gustatory cortex

Area of the brain that receives and interprets tastes from the tongue receives information from taste receptors of the tongue and pharynx, lies in the anterior portion of the insula and adjacent portions of the frontal lobe

Frontal eye field

Controls voluntary movement of the eyes controls learned eye movements individuals with damage to the frontal eye field can understand written letters and words but cannot read, because their eyes cannot follow the lines on a printed page

Motor and sensory areas of the cortex

Frontal lobe: Primary motor cortex - voluntary control of skeletal muscles Parietal lobe: Primary sensory cortex - conscious perception of touch, pressure, pain, vibration, taste and temperature Occipital lobe: Visual cortex - conscious perception of visual stimuli Temporal lobe: Auditory cortex and olfactory cortex - conscious perception of auditory (hearing) and olfactory (smell) stimuli All lobes: Association areas - integration and processing of sensory data, processing and initiation of motor activities

Projection fibers

Link the cerebral cortex to the diencephalon, brain stem, cerebellum, and spinal cord the entire collection of projection fibers is known as the internal capsule

Frontal lobe

Primary motor cortex (precentral gyrus) - neurons of the primary motor cortex direct voluntary movements by controlling somatic motor neurons in the brain stem and spinal cord - these cortical neurons are called pyramidal cells - they are like the keyboard to the piano - if you stimulate a specific motor neuron in the primary motor cortex, you generate a contraction in a specific skeletal muscle Somatic motor association area (premotor cortex)

Pariteal lobe

Primary sensory cortex (postcentral gyrus) - neurons in this region receive general somatic sensory information from receptors for touch, pressure, pain, vibration or temperature - you are aware of these sensations when nuclei in the thalamus relay the information to the primary sensory cortex Somatic sensory association area

Lateral sulcus

Separates temporal lobe from parietal and frontal lobes

Association fibers

These fibers connect areas within the same hemisphere interconnect areas of cerebral cortex within a single cerebral hemisphere Arcuate fibers - short fibers Longer association fibers are organized into discreet bundles or fasciculi Longitudinal fasciculi connect the frontal lobe to the other lobes of the same hemisphere

Insula

an island of cortex, lies medial to the lateral sulcus

The basal nuclei

are masses of gray matter that lie within each hemisphere deep to the floor of the lateral ventricle embedded in the white matter of the cerebrum part of a larger functional group known as the basal ganglia caudate nucleus - has a massive head and a slender, curving tail that follows the curve of the lateral ventricle lentiform nucleus - consists of a medial globus pallidus and a lateral putamen

Integrative areas

areas that receive information from many association areas and direct extremely complex motor activities these centers also perform complicated analytical functions are located in the lobes and cortical areas of both cerebral hemispheres deal with complex processes such as speech, writing, mathematical computation and understanding spatial relationships are largely restricted to either the left or the right hemisphere these centers include the general interpretive area and the speech center

Commissural fibers

connect one hemisphere to the other interconnect and permit communication between the cerebral hemispheres Corpus callosum and anterior commisure - bands of commissural fibers linking the hemispheres the corpus callosum alone contains more than 200 million axons, carrying some 4 billion impulses per second

Premotor cortex/somatic motor association

coordinates learned movements the neurons in the primary motor cortex must be stimulated by neurons in other parts of the cerebrum

Sensory association areas

cortical regions that monitor and interpret the information that arrives at the sensory areas of the cortex

Central sulcus

deep groove that separates frontal lobe from parietal lobe

Cerebral cortex

dominate the superior and lateral surfaces of the cerebrum the gyri increase the surface area of the cerebral hemispheres, and thus the number of cortical neurons they contain

Functions of the basal nuclei

involved with the subconscious control of skeletal muscle tone and the coordination of learned movement patterns these nuclei do not initiate particular movements, but once a movement is under way, the basal nuclei provide the general pattern and rhythm esp for movements of the trunk and proximal limb muscles the basal nuclei alter the motor commands issued by the cerebral cortex through a feedback loop activity of the basal nuclei is inhibited by neurons in the substantia nigra of the midbrain, which release the neurotransmitter dopamine if the substantia nigra is damaged or the neurons secrete less dopamine, basal nuclei become more active - the result is a gradual generalized increase in muscle tone and the appearance of symptoms characteristic of Parkinson's disease people with Parkinson's disease have difficulty starting voluntary movements, because opposing muscle groups do not relax

Prefrontal cortex of the frontal lobe

it integrates information from sensory association areas and performs abstract intellectual functions, such as predicting the consequences of possible responses

Cerbrum

largest part the brain, senses, learning, remembering, movement, personality conscious thoughts and all intellectual functions originate in the cerebral hemispheres much of the cerebrum is involved in processing somatic sensory and motor information gray matter in the cerebrum is located in the cerebral cortex and in deeper basal nuclei the white matter of the cerebrum lies deep to the cerebral cortex and around the basal nuclei

Somatic sensory association area

monitors activity in the primary sensory cortex - allows you to recognize a touch as light as a mosquito landing on your arm - giving you a chance to swat it before it bites you

Auditory association area

monitors sensory activity in the auditory cortex word recognition takes place in this association area

Visual association area

monitors the patterns of activity in the visual cortex and interprets the results

Corpus straitum

refer to the caudate and lentiform nuclei or to the caudate nucleus and putamen

Accessory Areas

regions of the cortex that interpret incoming data and coordinate a motor response

Longitudinal fissure

separates cerebral hemispheres

Parieto-occipital sulcus

separates the parietal lobe from the occipital lobe

The white matter of the cerebrum

the interior of the cerebrum constists mostly of white matter Association fibers Commissural fibers Projection fibers