Chapter 13; LO 8

Where is CSF produced and what is its function?

-CSF is produced by the four brain ventricles -Functions: buoyancy, protection, and environmental stability

What are the primary functions of the cerebellum?

-Cerebellum coordinates and "fine-tunes" movements. Ensure muscle activity follows correct pattern; adjusts movements initiated by cerebrum, ensuring smoothness; helps maintain equilibrium and posture

What are the basal nuclei and what is its function?

-gray matter deep in cerebrum -Function: helps regulate motor output; helps produce pattern and rhythm of walking movements -Putamen: helps control movements at subconscious level -Globus pallidus: influences thalamus to adjust muscle tone

Name the components of the limbic system and name the major functions of each

-Cingulate: receives input from the other components of the limbic system -Parahippocampal gyrus: associated with the hippocampus; helps form long-term memories -Amygdaloid body: involved in several aspects of emotion, especially fear. Can also help store and code memories based on how a person emotionally perceives them. -Olfactory bulbs/tract/cortex: help in experiencing how particular odors can provoke certain emotions or be associated with certain memories -Fornix: connects the hippocampus with other diencephalon limbic system structures -Anterior thalamic nucleus/ habenular nuclei/septal nucleus/mammillary bodies: interconnects with other parts of the limbic system and contribute to its overall function which is collectively process and experience emotions.

Compare and contrast coma, syncope, stupor, and vegetative state.

-Coma: a deep and profound state of unconsciousness from which the person cannot be aroused, even by repeated or painful stimuli. -Syncope: a brief loss of consciousness; often signals inadequate cerebral blood flow due to low blood pressure -Stupor: a moderately deep level of unconsciousness from which the person can be aroused only by extreme or painful stimuli -Vegetative state: a condition in which the person has lost his or her thinking ability as well as awareness of their surroundings.

What is disconnect syndrome?

-Condition where the transfer of information between the cerebral hemispheres through the corpus callosum is impaired.

List the functions of the hypothalamus

-Control of autonomic nervous system (influences heart rate; blood pressure; digestive activities; respiration) -Control of endocrine system (produces antidiuretic hormone and oxytocin -Regulation of body temperature; emotional behavior; food intake; and water intake

Briefly define the following structures and their function: Corpora quadrigemina, Substantia nigra, Cerebral peduncles

-Corpora quadrigemina: the four colliculi; reflex centers involving vision and hearing. -Substantia nigra: consists of bilaterally symmetrical nuclei within the midbrain. Houses clusters of neurons that produce the neurotransmitter dopamine which affects brain processes to control movement, emotional response, and ability to experience pleasure and pain. -Cerebral peduncles: the motor tracts located on the anterolateral surfaces of the midbrain. Descending axon bundles of the pyramidal system project through the cerebral peduncles and carry voluntary motor commands from the primary motor cortex of each cerebral hemisphere.

Define the following: Epidural Hematoma, Subdural hematoma, and Spina bifida

-Epidural hematoma:a pool of blood forming in the epidural space of the brain, usually due to a sever blow to the head. The adjacent brain tissue becomes distorted and compressed as a result of the hematoma continuing to increase in size. -Subdural hematoma: a hemorrhage that occurs in the subdural space between the dura mater and arachnoid mater. These hematoma's typically result from ruptured veins caused by either fast or violent rotational motion of the head. -Spini bifida: results when the caudal portion of the neural tube fails to close. There are two forms where one results in a large cystic structure in the back filled with CSF, covered by a thin layer of skin or meninges. More sever form is the partial defect of the vertebral arch, typically involving the vertebral lamina and spinous process.

What are the structures of the diencephalon? What are their functions?

-Epithalamus: forms posterior part of the roof of diencephalon,; covers third ventricle -Thalamus: receives signals from all conscious senses except olfaction; relays some signals to appropriate part of cortex and filters. -Hypothalamus: control of autonomic nervous system; influences heart rate, blood pressure, digestive activities, respiration, etc.

Name the major lobes of the brain, and briefly describe their functions

-Frontal lobe: pre-central gyrus controls voluntary movement; motor control, concentration, verbal communication, decision making, planning, personality -Parietal lobe: serves general sensory functions (e.g. evaluating shape and texture of objects) -Temporal lobe: hearing and smell -Occipital lobe: functions in vision and visual memories

How are the following cranial nerves tested: III, IV, VIII, IX, and XI.

-III (Oculomotor): examine if pupil constricts in response to light, examine eye movement -IV (Trochlear): examine eye movement -VIII: (Vestitbulocochlear): test hearing -IX (Glossopharyngeal): have patient open mouth and go "ahh" the soft palate should elevate, and the uvula should remain in the midline under normal conditions -XI (Accessory): have patient elevate or shrug shoulders or turn head to opposite side

What is the function of the Pineal gland?

-It is an endocrine gland that secretes the hormone melatonin which helps regulate day-night cycles (Circadian rhythm).

What are the mammillary bodies and where are they found?

-Mammillary bodies are paired peak-like nuclei that bulge anteriorly from the hypothalamus and function as relay stations in the olfactory pathways.

Know the name, number, nerve type, and function of each of the 12 nerves (Sensory information, somatic motor function, Parasympathetic motor function)

-Olfactory (I): smell -Optic (II): vision -Oculomotor (III): none -Trochlear (IV): none -Trigeminal (V): general sensory from anterior scalp, nasal cavity, oral cavity, auricle of ear -Abducens (VI): none -Facial (VII): taste from anterior two-thirds of tongue -Vestibulocochlear (VIII): hearing, equilibrium -Glossopharyngeal (IX): general sensory and taste from posterior one-third of tongue -Vagus (X): visceral sensory information from heart, lungs, most abdominal organs -Accessory (XI): none -Hypoglossal (XII): none

What is the function of the following areas of the cerebral cortex: prefrontal cortex, Broca's area, Wernicke's area, somatosensory area, premotor cortex, primary motor cortex?

-Prefrontal cortex: controls learned motor skills, coordinates movements of several muscle groups -Broca's area: It is involved mainly in producing speech, writing, and also in language processing and comprehension. -Wernicke's area: directs the muscles involved in speech production -Somatosensory area: receives information from sensory receptors in the skin, skeletal muscles, joints and tendons -Premotor cortex: controls learned motor skills, coordinates movements of several muscle groups -Primary motor cortex: controls skeletal muscle movement

What is the BBB and what is its function?

-The Blood Brain Barrier is a filtering mechanism of the capillaries that carry blood to the brain and spinal cord tissue. Its function is to regulate which substances can and cannot enter the interstitial fluid of the brain to help prevent exposure of nuerons in the brain to drugs, waste products, and variations in levels of normal substances that could adversely affect the brain.

Many medications introduced into the bloodstream cannot directly affect the neurons of the CNS- why?

-The formation of a Blood-brain barrier helps prevent the entering and exiting of certain substances in order to protect it from toxicity. This is why some medications cannot affect the neurons of the central nervous system. (alcohol is able to cross the BBB)

What is hemispheric lateralization?

-The functional difference between the left and right hemispheres.

What is the hippocampus and what is its function?

-The hippocampus is a small organ located within the brain's medial temporal lobe and forms an important part of the limbic system. Function: It is responsible for converting short term memory into long term memory.

What is the function of the reticular formation?

-The reticular formation is responsible for the sleep-wake cycle which mediates various levels of alertness

What is the general function of the Thalamus?

-The thalamus is the principal and final relay point for incoming sensory information that is processed and then projected to the appropriate lobe of the cerebral cortex. Receives signal from all conscious senses except olfaction. Also relays some signals to the appropriate part of cortex and filters out other information. -it works to correlate several important processes, including consciousness, sleep, and sensory interpretation.

What are the cranial meninges and what is their function?

-The three cranial meninges are the 3 connective tissue layers that separate and support the soft tissue of the brain from the bones of the cranium. -Function: enclose and protect some of the blood vessels that supply the brain and help contain and circulate cerebrospinal fluid. -From deep (closest to the brain) to superficial (farthest from the brain): the pia mater, the arachnoid mater, and the dura mater.

What is second impact syndrome and why is its significant?

-Where an individual experiences a second brain injury prior to the resolution of the first injury and develops severe brain swelling and possible death as a result. -For this reason, it is essential that the original TBI (traumatic brain injury) completely heals before an individual is allowed to resume behavior that may put the individual at risk for another TBI. Both severe TBI and repetitive TBI's may cause long-term cognitive deficits and motor impairment. May need occupational therapy to regain functions.

What is the probable cause of Alzheimer's disease, and what are its symptoms? (p. 522)

-While the underlying cause remains a mystery, genetics and environmental factors both seem to play a role in the development of Alzheimer's disease. The decrease in number of cerebral cortical neurons and a proliferation of two abnormal types of structures amyloid plaques and neurofibrillary tangles are thought to be causes.

What is the primary purpose of the primary motor cortex homunculus?

-Works as a diagram of the distribution of the primary motor cortex innervation to various body parts. The bizzare, distorted proportions of the homunculus body reflect the amount of cortex dedicated to the motor activity of each body part.

Name the Ventricles of the brain, what is their function?

Paired lateral condyles, Third ventricle, Fourth ventricle, and Cerebral aqueduct -Function: interconnect cavities that make CSF

Describe the 4 major structures of the adult brain as depicted on pages 485-87 of the text

The cerebrum: the origin of all complex intellectual functions; has two large hemispheres on superior aspect of brain; center of: intelligence, reasoning, thought, memory, judgement, voluntary motor visual and auditory activities. Diencephalon: made up of for main components including the thalamus, subthalamus, hypothalamus, and the epithalamus. The key function of linking the nervous system to the endocrine system via the pituitary gland. Brainstem: connects cerebrum, diencephalon, and cerebellum to spinal cord; contains ascending and descending tracts; contains autonomic nuclei of cranial nerves and reflex centers consists of: midbrain, pons, and medulla oblongata. Cerebellum: coordinates and fine-tunes movements; ensures muscle activity follows correct pattern; adjusts movements initiated by cerebrum, ensuring smoothness; helps maintain equilibrium and posture; receives proprioceptive information from muscles and joints