• Cutaneous Sensation • Basic modalities include touch, pressure, heat, cold, and pain. • Free receptors and encapsulated receptors near the surface of the skin • Proprioception: • Sensations from the musculoskeletal system (i.e., muscles, tendons, joint capsules and ligaments) • Proprioceptors are low threshold mechanoreceptors that inform CNS about movement and position by detecting the stretch of the tissue in which they lie.
EXPLAIN THIS! COM Displacement (cm) 0.75 0.5 0.25 1 no light heavy 0 eyes closed eyes open
• In the patellar tendon reflex (or knee-jerk; as an example of stretch reflex), explain the temporal procession of the following four neuronal activities, as discussed in the class: (1) sensory neuron, (2) motor neuron (the elongated extensor), (3) interneuron, and (4) motor neuron (the antagonist of the elongated extensor, or flexor).
Tendon Reflex… …is an example of the stretch reflex MS / GTO
Motor Development II • What was the experimental set up of Barela et al. (1999)? What were the measures? • Babies standing while using a block for posture. Center of Mass movement and Force applied to the block were measured. • At what stage did the infants use cutaneous sensation to enhance posture control? • Post Walking. • What is feedback and feedforward control? Which stage of development used feedback control? Feedforward control? Why?
Sensory info and types of control • Feedforward control: does not rely on sensory information to create movement • Fast reaching • Feedback control: relies on sensory information about performance and specific sensory input from the environment in which the movement is carried out • Driving a car
Vision • Describe the cortical processing in vision (1) when a person is unable to recognize objects, but could reach and grasp the object and (2) when a person has a reduced ability to locate objects but can recognize the object. Explain the two cortical pathways that are responsible for object recognition, object location, and movement.
information in the left visual field is processed by the left visual cortex. • (2) In the peripheral retina, the convergence (the ratio of photoreceptors to the retinal ganglion cells) is 100:1, indicating that due to the more convergence, the receptive field in peripheral retina is larger and the acuity is smaller.
• Are the following statements correct? If not, why incorrect? (1) The information in the left visual field is processed by the left visual cortex.
- Fall '11