Cerebrum Flashcards
What does the cerebrum consist of?
the diencephalon and the cerebral hemispheres
What is the cerebrum involved in?
- perception
- voluntary movements
- using language and nonverbal communication
- understanding spatial relationship
- using visual information
- making decisions
- consciousness
- emotions
- mind-body interactions
- memory
What is the laymen’s definition of cognition?
the process of knowing
What is the neurobiological definition of cognition?
the neural processes by which the brain integrates meaningful stimuli, memory, and internal motivations producing perceptional awareness and appropriate behavior
What are the 4 structures of the diencephalon?
- Thalamus
- Hypothalamus
- Epithalamus
- Subthalamus
*all structures with the term thalamus in their names
Where does the hypothalamus sit in reference to the thalamus?
inferior and anterior to it
Where does the epithalamus sit in reference to the thalamus?
superior and posterior to it
Where does the subthalamus sit in reference to the thalamus?
inferolateral to it
What is the thalamus?
A large egg-shaped collection of nuclei above the brainstem bilaterally
What are the 3 major anatomical groups of nuclei in the thalamus?
anterior
medial
lateral
The lateral group of nuclei is further divided into ____ and _____ tiers
dorsal and ventral
What are the 3 main functional groups of thalamic nuclei?
- Relay
- Association
- Nonspecific
What do relay nuclei do?
convey information from the sensory systems (except olfactory), the basal ganglia, or the cerebellum to the cerebral cortex
Where are all relay nuclei found?
in the ventral tier of the lateral group
What do association nuclei do?
process emotional and some memory information or integrate different types of sensation
What do nonspecific nuclei do?
regulate consciousness, arousal, and attention
What does the hypothalamus do?
it integrates behaviors with visceral functions
What are 5 functions that are orchestrated by the hypothalamus?
- Maintaining homeostasis
- Eating, reproductive, and defensive behaviors
- Emotional expression of pleasure, rage, fear, and aversion
- Regulation of circadian rhythms in concert with other brain regions
- Endocrine regulation of growth, metabolism, and reproductive organs
What is the major gland in the epithalamus?
the pineal gland
What is the pineal gland involved in?
regulating the circadian rhythms and influencing the secretions of the pituitary gland, adrenal and parathyroid glands, and the islets of Langerhans
The subthalamus is located ______ to the substantia nigra of the midbrain
superior
What is the subthalamus part of?
The basal ganglia
What is the subthalamus involved in?
regulating movement
What does the subthalamus facilitate?
basal ganglia output nuclei
What does the cerebral hemisphere consist of?
- subcortical structures
- cerebral cortex
What do the subcortical structures consist of?
subcortical white matters
- basal ganglia
- amygdala
What are the 3 categories of subcortical white matter?
- Projection fibers
- Commissural fibers
- Association fibers
Where do the projection fibers extend to and from?
Extend from subcortical structures to the cerebral cortex and from the cerebral cortex to the spinal cord, brainstem, brainstem and thalamus.
What are 3 examples of projection fibers?
- thalamocortical
- corticospinal
- corticobrainstem
What do commissural fibers do?
Connect homologous areas of the cerebral hemispheres
What is the largest group of commissural fibers?
Corpus callosum
What do association fibers do?
Connect cortical regions within one hemisphere
What do short association fibers connect?
adjacent gyri
What do long association fibers connect?
lobes within one hemisphere
What do the basal ganglia do?
They sequence movements, regulate muscle tone and muscle force, select and inhibit specific motor synergies, and are involved with cognitive functions
The cerebral cortex is a vast collection of what?
cell bodies, axons and dendrites covering the surface of the cerebral hemispheres
What are the 3 most common types of cortical neurons?
- Pyramidal
- Fusiform
- Stellate cells
What are the 6 layers of the cerebral cortex?
- molecular layer
- external granular layer
- external pyramidal layer
- internal granular layer
- internal pyramidal layer
- multiform layer
There are how many distinctive histological areas (cytoarchitectonic) in the cortex?
52
What are the 5 categories of the cerebral cortex that are identified based on functions?
- Primary sensory cortex
- Secondary sensory cortex
- Primary motor cortex
- Motor planning areas
- Association cortex
What does the primary sensory cortex do?
Discriminates among different intensities and qualities of sensory information
What does the secondary sensory cortex do?
Performs more complex analysis of sensation.
What does the primary motor cortex do?
Provides descending control of motor output.
What do motor planning areas do?
Organize movements
What does the association cortex do?
Controls behavior, interprets sensation, and processes emotions and memories
What are the 4 primary sensory areas of the cerebral cortex?
- primary somatosensory
- primary auditory
- primary visual
- primary vestibular
What does the primary somatosensory cortex do?
Discriminates shape, texture, or size of objects
The primary somatosensory cortex receives information from tactile and proprioceptive receptors via a three-neuron pathway. What are these 3 neurons?
- Peripheral afferent/dorsal column neuron
- Medial lemniscus neuron
- Thalamocortical neuron
What does the primary auditory cortex do?
Conscious discrimination of loudness and pitch of sounds
What does the primary vestibular cortex do?
discriminates among head positions and head movements
What does the primary visual cortex do?
Distinguishes intensity of light, shape, size, and location of objects
Describe the pathway via which visual information travels to the cortex
from the retina to the lateral geniculate body of the thalamus, then to the primary visual cortex
What are the 3 secondary sensory areas of the cerebral cortex?
- secondary somatosensory
- secondary visual
- secondary auditory
What is the function of the secondary somatosensory area?
sterognosis and memory of the tactile and spatial environment
What is the function of the secondary visual area?
analysis of motion and color and control of visual fixation
What is the function of the secondary auditory area?
Classification of sounds
The primary motor cortex is the source of most neurons in the _______ tract
corticospinal
What does the primary motor cortex control?
contralateral voluntary movements, particularly the fine movements of the hand and face
Is a greater proportion of the total area of the primary motor cortex devoted to neurons that control the hands and face or the trunk and proximal limbs?
hands and face
The motor planning areas are part of the cortex _____ to the primary motor cortex
anterior
What are the 3 motor planning areas?
- Supplementary motor area
- Premotor area
- Broca’s area
What is the supplementary motor area important for?
the initiation of movement, orientation of the eyes and head, and planning bimanual and sequential movements
What does the premotor area control?
trunk and girdle muscles via the medial upper motor neurons
What is Broca’s area responsible for?
planning movements of the mouth during speech and the grammatical aspects of language
Broca’s area is usually found in the ___ hemisphere
left
The cortex not directly involved with sensation or movement is called the ______ cortex
association
__% of the cerebral mantle is comprised of primary sensory and motor cortex
__% is termed associational cortex
25
75
What are 3 association areas of the cerebral cortex?
- dorsolateral prefrontal association
- parietotemporal association
- ventral and medial dorsal prefrontal association
What are the functions of the dorsolateral prefrontal cortex?
self-awareness and executive functions
What are the functions of the pareitotemporal prefrontal cortex?
- cognitive intelligence
- sensory integration
- problem solving
- understanding language and special relationships
What are the functions of the ventral and medial dorsal prefrontal association cortex?
- impulse control
- reactions to surroundings
- emotion
- motivation
- personality
_______ prefrontal association area connects with areas that regulate mood and affect.
Ventral
_____ dorsal prefrontal cortex perceives other’s emotions and makes assumptions about what other people believe and their intentions.
Medial
What is emotion?
a short-term subjective experience
What is mood?
a sustained, subjective, ongoing emotional experience
What are the 4 structures that recognize emotional stimuli and generate and perceive emotions?
- Amygdala
- Area 25 + Mediodorsal nucleus of the thalamus
- Ventral striatum
- Anterior insula
What does the amygdala do?
Detects emotional & social cues
Generates feelings of fear and disgust
What does area 25 + mediodorsal nucleus of the thalamus do?
generate sad mood and depression
What does the ventral striatum do?
reward oriented behavior and responses to conditioned stimuli
What does the anterior insula do?
awareness of emotions and of stimuli inside the body
Making decisions depends on what 3 things?
- Stimulus coding system
- Action selection system
- Expected reward system
When making a decision where the outcome is uncertain, the ____ loop is active
limbic
What are the 3 systems that create the stress response?
- Somatic nervous system
- Autonomic nervous system
- Neuroendocrine system
What are the 3 types of memory?
- Working
- Declarative
- Procedural
What does working memory involve?
temporary storage and manipulation of information
Which 2 cortices maintain, manipulate, and update information in working memory?
Prefrontal cortex and the parietotemporal association cortex
What does declarative memory involve?
facts, events, concepts, and locations
What are the 3 stages of declarative memory?
- Encoding
- Consolidation
- Retrieval
What does procedural memory involve?
knowledge of how to do actions and skills
What is required to store procedural memories?
practice
What are the 3 stages of procedural memory for motor learning?
- Cognitive
- Associative
- Automatic
Where does comprehension of the spoken language occur?
Wernicke’s area
Broca’s area is found ______ to Wernicke’s area.
anterior
What is perception?
The interpretation of sensation into meaningful forms
Perception is an active process, requiring interaction among what 3 things?
the brain, the body, and the environment
Wernicke’s area also comprehends what?
Spatial Perception
After visual information is processed by the secondary visual cortex what are the 2 directions in which it flows?
- Dorsally
- Ventrally
The dorsally directed visual stream is an ____ stream to which lobe?
action
frontal
The ventrally directed visual stream is a ____ stream to which lobe?
perceptual
temporal
