The Cerebrum Flashcards
What are the 5 Limbic structures?
1.) Hippocampus
2.) Amygdala
3.) Mammilary Bodies
4.) Anterior Thalamic Nucleus
5.) Subcallosal, Cingulate, Parahippocampal Gyri
Main role of the Hippocampus
Involved in memory
Why is fear the best emotion to study?
It is the least easy emotion to disguise
Main role of the Amygdala
Key center for control of the fear of emotion
What are the 4 structures of the Basal Ganglia?
1.) Caudate nucleus
2.) Lentiform nucleus
3.) Claustrum
4.) Amygdala
What structures are related to the basal ganglia, but not truly part of the BG?
1.) Subthalamic nuclei
2.) Substantia nigra
3.) Red nucleus
What is the Corpus Striatum?
The Caudate and Lentiform Nuclei
What are the 2 portions of the Lentiform nucleus?
1.) Putamen
2.) Globus Pallidus
How are the caudate and lentiform nuclei separated?
By the fibers of the internal capsule
The putamen is the more _______ portion of the lentiform nucleus
lateral
The globus pallidus is the more _____ portion of the nucleus
medial
What is the role of the substantia nigra?
Involved in muscle tone
Why muscle tone important?
It is the baseline level of muscle contraction; it is important in maintaining posture and it is going to have manifestations in their ability to make and control movements
A lack of muscle tone is an indication of what?
A nervous system disorder
What disease is associated with a degeneration of substantia nigra?
Parkinson’s disease
What does substantia nigra translate to?
Black substance
What is the basal ganglia involved in?
Motor planning
What is motor planning?
Making and inhibiting movements
What is the role of the Thalamus?
Relay and integration center for the cortex, basal ganglia, hypothalamus, and brainstem
Why is the thalamus important to audiology?
It is the first location where we combine/integrate auditory input and sensory input (seeing and hearing)
What is the role of the anterior section of the thalamus?
Related to limbic system and contributes to emotional tone
What is emotional tone?
How we drive and express our emotions (someone is happy and expresses they are happy)
What is the role of the medial section of the thalamus?
Integration of various sensory inputs; ties sensory input to emotion
What is the role of the lateral section of the thalamus?
Outputs to and influences sensory and motor cortex
Where does the thalamus output to?
Courses through the Caudate and Putamen of the Basal Ganglia to reach the cortex
What are the 4 functions of the thalamus?
1.) Sensory integration
2.) Sensory perception
3.) Part of the circuit between BG, cerebellum, and cortex
4.) Connections with reticular formation
What is neural arborization?
As you ascend any tract in the brain, the number of neurons expands
The lower the tract, the more redundancy in the system; the higher the tract, the less redundancy
What is the goal of the insular cortex?
To maximize the amount of cortical tissue to maximize the amount of cortex we can fit into the brainspace
Sulci
In-folding of the tissue; forms the grooves/canals of the cortex surface
Gyru
Out-folding of the tissue
What are the 4 lobes of the brain?
Frontal, parietal, temporal, occipital
What are Brodmann’s areas?
Areas of discrete populations of neurons; they have anatomical designations but are not functional designations
What is the Corpus Callosum?
Large fiber tract that connects the two hemispheres of the brain
How many fibers are in the Corpus Callosum?
200-350 million fibers
What is the Splenium of the CC?
Primarily visual fibers of the occipital cortex and some auditory fibers as well; most posterior portion
What is the Sulcus of the CC?
Site where most of the auditory fibers cross; primary and secondary auditory cortex, anterior to the splenium
What is the Trunk of the CC?
Site where the somatosensory and motor fibers of the parietal cortex cross
What is the Genu of the CC?
Site where the fibers of the frontal cortex cross; motor information and high-level information criss-cross back and forth; most anterior section
What is the Rostrum of the CC?
Site where olfactory fibers cross
What is dichotic listening?
Different signals are presented simultaneously to the two ears
Why is the the left hemisphere preferentially activated in dichotic listening tasks?
Left hemisphere is the crucial site for speech processing in most listeners
What is the right ear advantage?
Speech perception ability is better for sounds going into the right ear
Why does the right ear advantage work?
Contralateral crossover of the auditory nervous system
What is the transcallosal pathway?
Connects auditory cortex and association cortex areas between the two hemispheres
What could the right ear advantage be due to anatomically?
Deterioration of the transcollosal pathway
