Sensory and Motor pathways

• What type of nervous system is being considered in today's study material?

  Somatic NS
• What are the two main components being focused on in today's study material?

  Spinal nerves and spinal cord
• What is the term for sensory information in the context of the somatic nervous system?

  Afferent = Somatosensory
• What are the types of sensations that are typically associated with the skin?

  Touch, temperature, vibration, pain
• What are the body parts that are typically associated with joints and muscles?

  Joints, muscles
• What is the difference between motor and efferent in the context of the nervous system?

  Motor refers to the type of information, efferent refers to the direction of signal transmission
• What is the term for the innervation of skeletal muscles?

  Motor = Efferent
• What happens to reflexes as complexity increases in the evolution of organisms?

  Reflexes are modulated
• How do simple creatures typically respond to stimuli?

  Reflexes only
• What is the importance of independent function in organisms?

  Allows for decision-based activity
• What is the difference between reception and perception in the context of sensory information?

  Reception refers to the detection of stimuli, perception refers to the interpretation of stimuli
• What is the term for the process of assigning meaning to sensory information?

  From info. → meaning
• What is the role of memory in the context of sensory information?

  Allows for the storage and retrieval of information
• What are the two groups of tracts in the motor system?

  Lateral tracts, Ventromedial tracts
• What is the major tract in the lateral group of motor tracts?

  Corticospinal = “pyramidal tract”
• What type of muscle activity is associated with the lateral tracts?

  Conscious muscle activity
• What is the term for the tracts that are associated with subconscious muscle activity?

  Ventromedial tracts
• What is an example of subconscious muscle activity?

  Posture
• Where in the brain does motor information originate?

  Motor cortex, Cerebellum, Brain stem
• How does motor information travel from the brain to the muscles?

  Through a chain of two neurons: upper motor neuron and lower motor neuron
• What are the major sensory tracts in the spinal cord?

  * Dorsal columns

  * Spinothalamic tracts

  * Spinocerebellar tracts
• What is the term for the impairment that occurs as a result of damage to the spinal cord?

  Dependent on site of damage
• How does information travel to the brain in the context of the somatic nervous system?

  Through a chain of three neurons: 1st order, 2nd order, and 3rd order
• What is the term for the area of the brain that receives somatosensory information?

  Somatosensory cortex
• What happens to somatosensory information when it reaches the brain?

  It is integrated with other sensory or stored information
• What is the term for the crossing of nerve fibers from one side of the spinal cord to the other?

  Decussation
• What is the role of the cerebellum in motor control?

  Coordinates and regulates motor activity
• What is the difference between the dorsal columns and the spinothalamic tracts?

  Dorsal columns transmit proprioception and vibration, spinothalamic tracts transmit pain and temperature
• Why is the modulation of reflexes important in the evolution of organisms?

  Allows for the development of more complex behaviors and independent function