CSD 2230 HUMAN COMMUNICATION DISORDERS Topic 6 Language Disorders Adult Disorders Central Nervous System Anatomy, Physiology, and Damage

Neurons Basic building block of the nervous system Landmarks Cell body Nucleus Dendrites Axons

Neurons Functions Efferent neurons-carry information away from the brain to the periphery Motor neurons Afferent neurons-carry information from the periphery to the brain Sensory neurons Interneurons

Neural Communication Neurotransmitters Excitatory Inhibitory Action Potential

Central Nervous System Major landmarks Cerebrum Brainstem Cerebellum Spinal cord Meninges Cerebrospinal fluid

Cerebrum Left and right hemispheres four lobes frontal temporal parietal occipital gyri sulci

Cerebrum Longitudinal fissure Corpus callosum CD ROM Ch 9.01 & Ch 9.02 Lateral fissure Central fissure

Brainstem Center of the Cerebrum Basal Nuclei Thalamus Brainstem midbrain pons medulla

Cerebellum Connects to the brainstem by three pathways that allow for 1. Input of sensory info from the body 2. Output of signals for motor execution to the muscles 3. Input from the cerebrum for control of cerebellar function The cerebellum is important for balance and for coordinating various body movements.

Spinal Cord Peripheral Nervous System Cranial Nerves 12 pair Specialized for sensory and/or motor functions Spinal Nerves 31 pair Sensory and motor functions

Hemispheric Specialization Left hemisphere sequential functioning Speech and language Broca’s area is important for the programming and movements for speech production. Damage results in problems in the planning and execution of speech movements Wernicke’s area is critical for processing and understanding auditory information. Damage results in marked problems in auditory comprehension Right hemisphere holistic functioning Facial recognition, comprehending and expressing emotion, musical ability

Four Major Causes of Brain Damage 1. Stroke 2. Head injury 3. Infections and growths 4. Progressive degenerative diseases

Stroke Cerebrovascular accident Embolus Thrombosis Hemorrage Effects are immediate but there is a period of recovery

Head Injury Open head injuries Closed head injuries Severity and type of damage is variable

Tumors Space occupying lesions Malignant Benign Interior or exterior surface of the brain Symptoms usually include dizziness, headache, memory deficits, and generalized sensory and/or motor problems

Progressive Degeneration Multiple sclerosis Parkinson’s disease Amyotrophic lateral sclerosis (ALS) Alzheimer’s disease