CNS and PNS
The Central Nervous System consists of
The brain and spinal cord (Zelenke, n.d.)
What is considered the oldest part of the brain?
The brainstem (Zelenke, n.d.)
What is the function of ascending tracts? What are the major tracts?
Ascending tracts use sensory (afferent) pathways to bring the information our body senses to our brains (Hoit et al., 2022) (Zelenke, n.d.). This allows us to process sensations such as touch, pain, and proprioception. The major tracts include the Dorsal Column-Medial Lemniscal Pathway (transfers vibration, fine touch, and proprioception to the cerebral cortex), spinothalamic tract (transfers heavy touch, temperature, and pain), and spinocerebellar tracts (allows us to maintain our balance and muscle tone by transmitting proprioceptive stimuli to the cerebellum).
What is the function of the cerebrum?
This part of the brain is responsible for higher-level mental tasks, which includes problem-solving, memory, language, and cognition (Hoit et al., 2022) (Zelenke, n.d.) . Regarding speech-language pathology, this is where motor and sensory information meet to help us produce movements and create perceptions about our environments, thus allowing us to communicate with others. The right and left hemispheres send information through the corpus callosum to transmit information from one side to the other. People who have damage in this area may experience aphasia, cognitive-communication disorders, or apraxia of speech, thus impacting their ability to produce and comprehend language.
Which are the two hemispheres of the brain?
The left and right hemispheres (Zelenke, n.d.)
How many divisions does the brainstem have?
Three (Zelenke, n.d.)
What is the function of descending tracts? What are the two major tracts called?
The descending tracts help us create movement in our body by transmitting motor (or efferent) directions from our brain to the rest of our body (Hoit et al., 2022) (Zelenke, n.d.). These tracts send signals to the muscles responsible for controlling out voice, speech, and ability to swallow. The pyramidal and extrapyramidal tracts are its two major divisions.
What is the function of the limbic system?
The limbic system controls our ability to feel emotions and motivation, as well as process memories (Hoit et al., 2022) (Zelenke, n.d.). This region ascribes emotions to behaviors, thus impacting the way in which we react to our environment. The cingulate gyrus, amygdala, and hippocampus in particular are key structures within this area that influence our personality and emotions. Damage to this system may cause clients to experience irregularities in the way they experience emotions, memory, and motivation, thus impacting how they navigate treatment and cope with their communication disorder.
How many cranial nerves are there?
12 (Zelenke, n.d.)
What are the three divisions of the brainstem?
Midbrain, pons, and medulla oblongata (Zelenke, n.d.)
What do the pyramidal tracts do?
The pyramidal, or direct, tracts contain the corticospinal and corticobulbar tract. This tract originates from our brain cortex (Hoit et al., 2022) (Zelenke, n.d.). The corticospinal tract manages the minor voluntary movements our limbs must perform (as well as the trunk), while the corticobulbar tract manages the movements performed by our head, face, and neck by transferring signals to our cranial nerves. To summarize, these movements are voluntary and finely coordinated.
What is the function of the basal ganglia?
The basal ganglia manage our motor movements and muscle tone (Hoit et al., 2022) (Zelenke, n.d.). It is comprised of numerous nuclei bundled together. The ganglia ensures that our movements are smooth and precisely- coordinated, as opposed to creating the movements themselves. Difficulties related to this include illnesses that modify a person’s ability to speak with the appropriate, prosody, rate, and rhythm, such as Parkinson’s disorder and Huntington’s disease.
How many spinal nerves are there?
31 (Zelenke, n.d.)
What does the brainstem connect?
The brain and spinal cord (Zelenke, n.d.)
What do extrapyramidal tracts do?
The extrapyramidal, or indirect, tracts originate from our brainstem and control involuntary movements (Hoit et al., 2022) (Zelenke, n.d.). These movements include regulating posture, muscle tone, and automatic movements. The tracts do not initiate these movements but rather maintain them as we are moving.
What is the function of the thalamus?
The thalamus, a cluster of nuclei that has been coined as the “relay center” of the brain, organizes sensory information our body receives and directs it to the region of the cerebral cortex it belongs to (Hoit et al., 2022) (Zelenke, n.d.). It is also integral in managing attention, consciousness, and awareness. Thalamic dysfunction can bring about ataxic speech or a deficiency in sensory information, as dysfunction can inhibit a client’s ability to process sensory feedback needed for speech, swallowing, or articulation.
How many systems does the Peripheral Nervous System have?
Three (Zelenke, n.d.)
Which part of the brain connects the brainstem to the spinal cord?
The medulla oblongata (Zelenke, n.d.)
What clinical relevance does this have for us in speech-language pathology?
Clients with spastic dysarthria experience weakness and spastic muscles due to damaged pyramidal tracts (Hoit et al., 2022) (Zelenke, n.d.). Clients with hypokinetic or hyperkinetic have damaged extrapyramidal tracts, which causes involuntary or stiff movements, alongside tremors.
What is the function of the hypothalamus?
The hypothalamus, which resides under the thalamus, manages homeostasis by modulating body temperature, libido, water balance, hunger, satiation, and emotions (Hoit et al., 2022) (Zelenke, n.d.). It also manages the hormones our pituitary gland releases. Clients with a damaged hypothalamus may experience abnormal sleep cycles, appetite, and stress responses. These factors may also impact how a client navigates treatment, as their energy levels or vocal quality may be diminished, plus their ability to recover may be compromised.