Brain Anatomy Flashcards
What does the midbrain connect?
Connects:
- Pons to cerebrum
- Superior peduncles connect midbrain to cerebellum
What does the Motor Loop (putamen loop) do?
Location:
- Originates in precentral motor & postcentral somatosensory areas
- Projects to and excites putamen neurons
Functions:
- Reinforce selected movement patterns
- Anticipatory movements
What lobe is Broca’s Area located in?
Frontal Lobe (typically LEFT hemisphere)
What does the Epithalamus do?
- Habenular Nuceli: integrate olfactory, visceral & somatic afferent pathways
- Pineal Gland:
- Secretes hormones that influence the pituitary gland and several other organs
- influences circadian rhythm
What do Association Fibers do?
Connect different portions of the cerebral hemispheres, allowing cortex to function as an integrated whole
What do Projection Fibers do?
Connect cerebral hemispheres with other portions of the brain and spinal cord
What does the Visual Association Cortex do?
Process visual stimuli
What are the basic functions of the Limbic System?
Instincts and emotions to preserve the individual:
- Feeding
- Aggression
- Endocrine aspects of sexual response
What important structure is located in the Parietal Lobe?
Postcentral gyrus
What are the 3 types of white matter?
- Transverse (commissural) fibers
- Projection fibers
- Association fibers
What 4 structures make up the Diencephalon?
- Thalamus
- Subthalamus
- Hypothalamus
- Epithalamus
What are the 3 components of the Brainstem?
- Midbrain
- Pons
- Medulla Oblongata
What does the Primary Visual Cortex do?
Receives/processes visual stimuli
Where is the Postcentral Gyrus located?
Parietal Lobes
What do the Superior and Inferior Colliculus do?
- Superior Colliculus: relay station for vision and visual reflexes
- Inferior Colliculus: relay station for hearing and auditory reflexes
What lobe is the Primary Auditory Cortex located in?
Temporal Lobe
What does the Medulla Oblongata do?
- Connects spinal cord with pons
- Corticospinal tracts cross in pyramids
- Cranial nerve nuclei: hypoglossal, dorsal nucleus or vagus & vestibulocochlear
- Important centers for: cardiac, respiratory, and vasomotor centers
What does the Subthalamus do?
Involved in control of several functional pathways for sensory, motor, & reticular function
The Temporal Lobe is made up of these three main structures/areas
- Primary Auditory Cortex
- Associative Auditory Cortex
- Wernicke’s Area
What does the Primary Auditory Cortex do?
Receives/processes auditory stimuli
What is white matter?
myelinated nerve fibers located centrally
What main structures are in the Midbrain?
- Cerebral Peduncles
- anterior: substania nigra
- posterior: tegmentum
- Superior & Inferior Colliculus
- Periaqueductal Gray
What do Transverse Fibers do?
Interconnect 2 hemispheres
(corpus callosum, anterior commissure, & hippocampal commissure
What lobe is Wernicke’s Area located in?
Temporal Lobe (typically LEFT hemisphere)
What does the Periaqueductal Gray do?
Contains endorphin-producing cells & descending autonomic tracts
What does the Limbic Circuit do?
- Originates in prefrontal and limbic areas of cortex
- Organize behaviors and for procedural learning
What does the Pons do?
- Connects medulla oblongata to midbrain, allowing passage of important ascending & descending tracts
- Anterior basal part acts as a bridge to cerebellum (middle cerebellar peduncle)
- Midline raphe nuclei projects widely and are important for modulating pain and controlling arousal
- Tegmentum contains several important cranial nerve nuclei: abducens, trigeminal, facial, vestiobulocochlear
What does the Thalamus do?
- Sensory Nuclei:
- Integrate & relay sensory info from body, face, retina, cochlea, and taste receptors to cerebral cortex & subcortical regions (smell is the exception)
- Motor Nuclei
- Relay motor info from cerebellum and globus pallidus to precentral motor cortex
- Other Nuclei
- Assist in integration of visceral and somatic functions
What is the Basal Ganglia and what does it do?
- Masses of gray matter deep within the cerebral hemispheres
- striatum, globus pallidus, subthalamic nucleus & substantia nigra
- Forms an associated motor system with other nuclei in the subthalamus and midbrain
What lobe is the Precentral Gyrus located in?
Frontal Lobe
What does the Associative Auditory Cortex do?
Process auditory stimuli
What does the Prefrontal Cortex do?
Controls emotions and judgements
What is the purpose of the Cerebellum?
- Connects with vestibular system
- Equilibrium
- Maintenance of posture and voluntary movement
- Smooth coordination of movement
- Accurate force, direction, and extent of movement
- Motor learning
- Sequencing of movements
What does the Oculomotor Circuit (caudate loop) do?
- Originates in frontal and supplementary motor eye fields
- Projects to caudate
- Functions with saccadic eye movements
What does the Lateral Central Fissure separate?
Separates temporal lobe from frontal and parietal
What are two main cortexes in the Occipital Lobe?
- Primary Visual Cortex
- Visual Association Cortex
What does the Longitudinal Cerebral Fissure separate?
the two hemispheres
What does the Substantia Nigra do?
- Large motor nucleus connecting with basal ganglia and cortex
- Important in motor control and muscle tone
The Frontal Lobe is made up of these three main structures/areas
- Precentral Gyrus
- Prefrontal Cortex
- Broca’s Area
What lobe is the Visual Association Cortex located in?
Occipital Lobe
What are the 3 circuits/loops in the Basal Ganglia?
- Oculomotor Circuit (caudate loop)
- Motor Loop (putamen loop)
- Limbic Circuit
What lobe is the Associative Auditory Cortex located in?
Temporal Lobe
What does the Central Sulcus separate?
frontal lobe from parietal lobes
What lobe is the Prefrontal Cortex located in?
Frontal Lobe
What does the Hypothalamus do?
- Integrates/controls functions of autonomic nervous system & neuroendocrine system
- Maintains body homeostasis (water, body temp, eating, water balance)
What is the main role of the Parietal Lobe?
Receives fibers conveying touch, proprioception, pain & temperature
(from opposite side of body)
What are Gyri?
Crests in grey matter
What are sulci?
Fissures in grey matter
What does the Tegmentum do?
- Contains all ascending tracts and some descending tracts
- Important for coordination
- Contains cranial nerve nuclei: oculomotor & trochlear
What does the Precentral Gyrus do?
Primary motor cortex for voluntary muscle activation
What does the Postcentral Gyrus do?
Primary sensory cortex for integration of sensation
What is the Insula?
- Deep within the lateral sulcus
- Associated with visceral function
What does Broca’s Area do?
Controls motor aspects of speech.
What lobe is the Primary Visual Cortex located in?
Occipital Lobe
What does Wernicke’s Area do?
Language Comprehension