Notes: Assignment 4 due Fri December, 10 th Extra Credit – answer questions on the form

22 “Plasticity, Recovery, and Rehabilitation of the Adult Brain” Human Neuropsychology (486 / 686) Lecture Chapter 25.

Cortical Plasticity and the Intact Adult Brain Neural Plasticity can be studied through: Neural Plasticity can be studied through: Observable behavior Cerebral maps Synaptic organization Physiological organization Molecular structure Mitosis

Inferring Plasticity from Changes in Behavior Prism Adaptation Prism Adaptation Subjects fitted with prisms can adapt to the shifted visual world Neural changes occur in the premotor cortex and visual cortex Changes disappear after prism removal

Plasticity in Cortical Maps Motor and sensory maps are altered by experience Motor and sensory maps are altered by experience

Plasticity in Synaptic Organization Computational challenge is associated with structural complexity Computational challenge is associated with structural complexity

Plasticity in Physiological Organization Long-term Long-termpotentiation

Plasticity in Molecular Structure and Mitosis: Plasticity in Molecular Structure and Mitosis: - Changes in gene expression - Neurogenesis – olfactory bulb and hippocampus Both occur in response to experience / injury Experience dependent changes: Experience dependent changes: - Drugs change neural morphology - Environment and drug interactions

Plasticity and Recovery from Injury Physiological Events Physiological Events Compensation vs Recovery Compensation vs Recovery

Examples of Function Restitution Recovery from Motor-Cortex Damage Recovery from Motor-Cortex Damage Recovery from hemiplegia Return of reflexes Rigidity Facilitated Grasping Voluntary grasping Complete recovery occurs in about 30% of patients

Examples of Function Restitution Recovery from Aphasia Recovery from Aphasia

Examples of Function Restitution Recovery from Traumatic Lesion Recovery from Traumatic Lesion 50% no recovery at all 50% no recovery at all Recovery from Surgical Lesions Recovery from Surgical Lesions no recovery in most cases recovery of some memory abilities

Plasticity in the Injured Brain Functional Imaging after Cerebral Injury Functional Imaging after Cerebral Injury Post-stroke changes : 1. Functional improvement is associated with activation of remaining sensorimotor cortex 2. Movement of the limbs activates motor cortex along the rim of the injury and often activates regions of the face area 3. Larger regions of activation in the parietal and premotor areas during language and motor functions 3. Reorganization takes place bilaterally 4. Capacity for reorganization declines with increases in stroke size and age Considerable variability exists between patients

Physiological Mapping after Cerebral Injury Remapping: loss of the hand area from the cortex Therapy after removal of the hand area facilitates recovery

Therapeutic Approaches to Brain Damage Rehabilitation Rehabilitation Movement Therapy Cognitive Rehabilitation Pharmacological Therapies Pharmacological Therapies Brain Stimulation Brain Stimulation Brain-Tissue Transplants and Stem-Cell Induction Brain-Tissue Transplants and Stem-Cell Induction

1. Memory impairment associated with retrograde amnesia following traumatic brain injury are: a. more pronounced for older memories than for newer memories b. more pronounced for newer memories than for older memories c. the same regardless of the age of the memory d. greater for information learned after the point of injury

2. One of the proposed differences between implicit and explicit memory is that explicit memory depends on __________ processing to a greater extent than does implicit memory. a. “top-down” b. “bottom-up” c. neutral d. temporal lobe

3. The fundamental sounds in language are called: a. morphemes b. lexicals c. phonemes d. vowels

4. Cases of brain damage in deaf individuals who use sign language suggest that the organization of gestural language: a. has its focus in the right parietal cortex along with other spatial functions b. is very similar to that of spoken language with the left hemisphere dominant for both c. is inconclusive as no particular pattern has emerged d. is predominantly controlled by subcortical structures

5. Our ability to use information outside of our conscious awareness to guide our behavior is known as: 1. selective attention b. gist c. unconscious deduction d. unconscious inference

6. A patient who experiences no difficulties finding her way around the home where she lived for most of her adult life but becomes spatially disoriented in her most recent home is suffering from __________ disorientation a. retrograde b. egocentric c. anterograde d. allocentric

7. What is autonoetic awareness? 8. What are the three main parts of the Wernecke-Geswind model? 9. Compare and contrast Damasio’s somatic marker theory of emotion with Ledoux’s cognitive emotional interactions theory.