exam 1 moved to the 31 of january thebrainmcgill simple to complex neurological level intermediate...
TRANSCRIPT
Exam 1
• Moved to the 31 of January
Thebrainmcgill
• Simple to complex
• Neurological level
• Intermediate level
• Midsagittal view
Slides 5, 6, 8, 9
• Could be on test
• So be ready to label structures and their functions
Brainstem Cerebellum & Deep Structures
• Brainstem: Midbrain, Pons, Medulla
• Thalamus
• Cerebellum
• Basal Ganglia
• Limbic System
Nuclei
Collection of neuronal somas in the deeper brain structures
Nerves
Contain the axons from the neuron cell bodies aka soma
Nuclei is a collection of neuronal cell bodiesNerve is a collection (fascicle) of neuronal axons
Brainstem
• Primitive Part of Brain– Midbrain aka mesencephalon– Pons metencephalon together with cerebellum– Medulla Oblongata myencephalon
MIDBRAIN
• Functions in visual and auditory orientation reflexes, maintaining posture and voluntary movements of body and face
• Contains nuclei for cranial nerves 3, oculomotor; 4, trochlear; 6, abducens
• a thoroughfare for axons entering and leaving brain.
PONS
• Central portion of brainstem• Regulates respiration, thoroughfare for motor and
sensory fibers, controls movement of face & jaw muscles, eye movement & sensation to face
• Contains nuclei for cranial nerves: 5, trigem; 7, facial
• Trigeminal, abducens, facial, vestibulocochlear nerves run through it
Medulla Oblongata
• Caudal portion of brainstem, leads to spinal cord
• Contains nuclei for CN 9-12 involved in speech (tongue & vocal cords), swallowing, move neck & shoulder muscles, salivation, taste
• Thoroughfare for afferent & efferent fibers
Motor Modulation Systems
• Cerebellum
• Basal Ganglia
CEREBELLUM
• derived from hindbrain but not part of brain stem.
• connected to pons and medulla by cerebellar peduncles that are made up of axons entering and leaving the cerebellum
• 4th ventricle separates it from brain stem.
Cerebellum
• Major functions– Coordinate muscle activity– Posture– Equilibrium– Spatial Reasoning
Function• Motor control for muscle coordination and in
planning complicated movements• Cognitive tasks involved in learning and memory
of motor task.• Lesions to humans or animals shows that distinct
areas of the cb are necessary for spatial reasoning, keeping muscle tone during voluntary movement or reflexes
• people can't walk in a coordinated smooth manner after cb lesion ie they appear to walk as if drunk
Cerebellar Lobes
• Rostral or anterior• Caudal or posterior• Vermis• Flocculonodular
• Folia is a term used from gyri in cerebellar cortex that are smaller than in cerebral cortex
Deep Cerebellar Nuclei
• Emboliform
• Dentate
• Globose
• Fastigial
• Are main output neurons from cerebellum
Deep Brain Nuclei• Diencephalon: processing sensory & motor
information & endocrine role
• Basal Ganglia-Striatum: 3 forebrain nuclei involved in motor control
• Limbic System: Involved in regulating emotion, motivation & homeostasis
DIENCEPHALON• Anterior to midbrain and forms the walls of
the third ventricle.
• Consists of two parts, the thalamus and hypothalamus
– Thalamus: processes sensory info & relays motor info
– Hypothalamus: part of limbic system, controls pituitary
THALAMUS• Subdividing into 6 nuclei• Relay station for afferent incoming sensory
information on the way to the appropriate cortical regions.
• Several nuclei in the thalamus receive visual information from the optic nerves
• Other nuclei receive auditory information and motor information.
HYPOTHALAMUS• involved in maintaining homeostasis, controls body
temperature, blood pressure, salt and water levels• initiates and supresses eating, drinking• Activates and inhibits pituitary gland, a
neuroendocrine organ• regulates autonomic function such as blood pressure
& temperature• involved in emotional responses such as changes in
blood pressure/heart rate/respiration, blushing and sweating
BASAL GANGLIA
• Nuclei surrounding thalamus with common function– 3 components
• putamen, globus pallidus, caudate nucleus aka striatum
• Substantia nigra
• Subthalamic nuclei
Deep Brain Nuclei involved in starting and stopping movementDisease to substantia nigra causes parkinson’s disease
Function
• Function in initiation and planning of voluntary movement and tone of antigravity muscles.
Limbic System
• Limbic means “border/edge”
• Function to– Regulate visceral motor function– Emotions , fear irritability depression aggresion– Memory– Olfaction—food aversions
Stop Here
Slides 40-43 have details that will not be included in the test. They will be
covered during the 2nd half of the course.