Week 7 - Chapter 14: The Brain
The major parts of the brain are:
Cerebellum, diencephalon, and cerebrum.
The brain is protected by:
Cranial cavity bones and the cranial meninges
From superficial to deep: Dura mater, arachnoid mater, and pia mater
Cranial meninges
Blood flow to the brain is mainly via:
Internal carotid and vertebral arteries.
Any interruption of the oxygen or glucose supply to the brain can result in:
Weakening of, permanent damage to, or death of brain cells.
The blood–brain barrier:
- Causes different substances to move between the blood and the brain tissue at different rates
- Prevents the movement of some substances from blood into the brain
Cerebrospinal fluid is formed in the:
Choroid plexuses
Cerebrospinal fluid:
Circulates through the lateral ventricles, third ventricle, fourth ventricle, subarachnoid space, and central canal
Mechanical protection, chemical protection, and circulation of nutrients.
Cerebrospinal fluid functions
Nuclei of the medulla are associated with what nerves:
Vestibulocochlear (VIII), glossopharyngeal (IX), vagus (X), accessory (XI), and hypoglossal (XII) nerves.
The medulla oblongata is continuous with:
Superior part of the spinal cord
Nuclei of the medulla:
Gracile nucleus
Cuneate nucleus
Gustatory nucleus
Cochlear nuclei,
Vestibular nuclei
Olivary nucleus
The olivary nucleus:
Provides instructions that the cerebellum uses to adjust muscle activity when you learn new motor skills
Nuclei of the medulla coordinate:
Vomiting, swallowing, sneezing, coughing, and hiccupping
The pons is ______ to the medulla.
Superior
Contain both sensory and motor tracts:
Medulla, pons, midbrain
Pontine nuclei relay ______ related to voluntary skeletal movements from the cerebral cortex to the cerebellum.
Nerve impulses
__________ nuclei, which are present in the pons and medulla, are part of the equilibrium pathway to the brain.
Vestibular nuclei
Nuclei of the pons are associated with what nerves:
Trigeminal (V), abducens (VI), and facial (VII) nerves and the vestibular branch of the vestibulocochlear (VIII) nerve.
The _______ connects the pons and diencephalon
Midbrain
The _______ colliculi of the midbrain coordinate movements of the head, eye, and trunk in response to visual stimuli
Superior colliculi
The ______ colliculi of the midbrain coordinate movements of the head, eyes, and trunk in response to auditory stimuli.
Inferior
A large part of the _______ consists of small areas of gray matter and white matter called the reticular formation
Brainstem
Helps maintain consciousness, causes awakening from sleep, and contributes to regulating muscle tone
Functions of the reticular formation
It connects to the brainstem by three pairs of cerebellar peduncles.
The Cerebellum
Smooths and coordinates the contractions of skeletal muscles. It also maintains posture and balance.
Functions of the Cerebellum
Consists of two lateral hemispheres and a medial, constricted vermis
The Cerebellum
Surrounds the third ventricle and consists of the thalamus, hypothalamus, and epithalamus.
The diencephalon
The ______ is superior to the midbrain and contains nuclei that serve as relay stations for most sensory input to the cerebral cortex.
thalamus
Contributes to motor functions and plays a role in maintenance of consciousness
Thalamus
________ is inferior to the thalamus. It controls the autonomic nervous system, produces hormones, and regulates emotional and behavioral patterns
Hypothalamus
The body's internal clock:
Suprachiasmatic nucleus
The _______ regulates eating and drinking
Hypothalamus
The _______ consists of the pineal gland and the habenular nuclei.
Epithalamus
The pineal gland secretes _______
melatonin
The ______ is the largest part of the brain.
Cerebrum
Its cortex contains cerebral gyri, cerebral and interlobar sulci, and cerebral fissures.
Cerebrum
The cerebral hemispheres are divided into four lobes:
Frontal, parietal, temporal, and occipital
The white matter of the _____ consists primarily of myelinated axons extending to other regions as association, commissural, and projection fibers.
Cerebrum
The corpus striatum in the cerebrum functions:
Help initiate and terminate movements, suppress unwanted movements, and regulate muscle tone.
It functions in emotional aspects of behavior and memory.
The limbic system
The sensory areas of the cerebral cortex allow perception of:
Sensory information
The motor areas of cerebral cortex control the execution of:
Voluntary movements
This cortex processes sensations like touch and pain from specific body areas
The primary somatosensory cortex
The cortexes handle visual, sound, taste, and smell perceptions
The primary visual, auditory, gustatory, and olfactory cortices
The _______ cortex is involved in personality, intellect, judgment, and abstract thinking.
Prefrontal
This cortex identifies and discriminates odors
Orbitofrontal cortex
______ area interprets speech meaning
Wernicke’s
_______ area synthesizes sensory inputs for coherent thought.
Common integrative area
________ area connects present visual inputs with past experiences for recognition
The visual association
The _______ area helps identify object shape and texture through touch and maintains memories of sensory experiences.
Somatosensory associaton area
Motor areas include the ______ motor cortex for muscle control, _______ cortex for movement planning
Primary, Premotor
______ area controls speech production.
Broca's
Each brain hemisphere has distinct functions:
The _____ specializes in language and reasoning, while the ____ focuses on artistic awareness and spatial perception, controlling opposite body sides.
Left, right
____ pairs of cranial nerves originate from the nose, eyes, inner ear, brainstem, and spinal cord.
12
The _______ nerve is entirely sensory. It contains axons that conduct nerve impulses for olfaction (sense of smell).
Olfactory (I)
The ______ nerve is purely sensory. It contains axons that conduct nerve impulses for vision.
Optic (II)
These 3 nerves are the cranial nerves that control the muscles that move the eyeballs
- They are all motor nerves.
The oculomotor (III), trochlear (IV), and abducens (VI)
The ______ nerve is a mixed cranial nerve and the largest of the cranial nerves.
- It conveys touch, pain, and thermal sensations, and controls chewing muscles/middle ear muscle.
Trigeminal (V)
The _______ nerve is a mixed cranial nerve. It conveys taste from the front two-thirds of the tongue, processes touch and pain from the external ear, controls facial expression muscles, regulates middle ear muscle activity, and stimulates tear and saliva production.
Facial (VII)
The _______ nerve is a sensory cranial nerve.
- It conveys sensory information for audition (hearing) and equilibrium (balance)
Vestibulocochlear (VIII)
The ______ nerve is a mixed cranial nerve.
- It conveys taste from the back third of the tongue, processes proprioception from swallowing muscles, and touch, pain, and thermal sensations from the external ear and upper pharynx; monitors blood pressure and gas levels, aids in swallowing, and stimulates saliva secretion.
Glossopharyngeal (IX)
The ______ nerve is a mixed cranial nerve.
- It conveys taste from the epiglottis, proprioception from throat and voice box muscles, and sensations from the external ear and organs; monitors blood pressure and gas levels, and regulates swallowing, vocalization, coughing, digestive motility, respiratory constriction, and heart rate.
Vagus (X)
The ______ nerve is a motor cranial nerve. It controls movements of the head.
Accessory (XI)
The _________ nerve is a motor cranial nerve. It promotes speech and swallowing.
Hypoglossal (XII)
The nervous system develops from the ______ plate
Neural plate
A cranial meninges is a:
Protective layer of tissues that covers and surrounds the brain and spinal cord.