Utilizing Principles of Neuroplasticity to Guide Language Rehabilitation Peter Meulenbroek, MA CCC-SLP University of Wisconsin-Madison
1. Outline Assumptions Outline of Talk 2. Outline Principles of Neurological Recovery 3. Discuss Limitations of Research Presented 4. Introduce a framework for future investigation of Aphasia treatment and recovery
Assumptions Behavior = Brain Functions Behavior = Complex Processes Processes = Internal & External I believe that rehabilitation is potent Gonzalez-Rothi (2001)
Mechanisms of Behavioral Change
Principles of Neuroplasticity Use It or lose It Use It and Improve It Specificity Repetition Matters Intensity Matters Time Matters Age Matters Salience Matters Transference Interference Kleim & Jones, 2008
Use It or Loose It Learned disuse If the patient isn t using certain functions those skills will decline Neurological effect include number of neurons number of synapses cortical representation
Use it and improve it Neurons that fire together, wire together
The Nature of Experience Influences the Nature of Change Very important stimuli may be learned in a single trial In animals, an enriched environment = Better learning - particularly complex tasks
The Nature of Recovery Includes Socialization Craft et al., 2005
Experience Changes the Brain in Specific Ways Plasticity = Change in response to internal or external factors Change occurs in both normal and pathological conditions Performance on one task may generalize, depending on the underlying substrate changes that occur Change requires a LOT of repetitions Pre-morbid connections have developed over a lifetime of genetic programming and experience: may be resistant to change Without carefully-planned intervention, change may not occur spontaneously and learned non-use may occur
Timing is Everything Effects of experience in the developing nervous system may be substantially different than in a mature or aged nervous system Intensive behavioral therapy in the acute stage postinjury may not be effective and may be detrimental to recovery Intervention in the chronic stage post-injury may be most effective if delivered with high intensity over a relatively brief period
The Recovered Brain Remains Sensitive to Drug and Other Effects Neurotransmitter systems and physiological properties of neurons may be altered postinjury, despite normal-appearing behavior Drugs that affect damaged systems may impair performance Behavioral impairments may be associated with underlying functional damage
Limitations in the application of animal research to humans...monkeys don t talk!
US vs. THEM Sincich et al., 2003
Inter-Species Differences Behaviors are performed for different functions
Behavioral Measures might not represent the type of memory humans use
Modeling the young male construction worker Lateral Fluid Percussion Virginia Commonwealth University Electric Cortical Contusion Impactor
Experimental paradigms in animals human rehabilitation Differences between animal and clinical contexts: Hundreds to thousands of repetitions Tightly controlled environment and pre-morbid experience Genetic control Pre-treatment Women Secondary complications Language, declarative memory, executive function Rehabilitation
What can we take from this? The ideal rehabilitation environment would consider these factors: Plasticity at any age, internally vs. externally driven Generalization to the extent that behaviors are similar Frequency of repetitions required Meaning of stimuli to patient Opportunity for interactions with enriched environment Age at injury and age of injury Intervention timing: acute vs. chronic Pre-injury skills Sensitivity of recovered system to drugs and other effects Secondary Injury, coma and various injury mechanisms Surgical interventions and Intensive Care factors
From Principles to Treatment Use It or lose It Use It and Improve It Specificity Repetition Matters Intensity Matters Time Matters Salience Matters Age Matters Transference Interference Kleim & Jones, 2008
Lyn Turkstra, PhD Thank You Anastasia Raymer, PhD Lisa Edmonds, PhD Laura Murray, PhD My colleagues from The University of Wisconsin - Madison & Spaulding Rehabilitation Hospital, Boston
Sources Kleim, J. A., & Jones, T. A. (2008). Principles of experience-dependent neural plasticity: Implications for rehabilitation after brain damage. JSLHR, 51(1), S225- SS239. Raymer AM et al. (2008) Translational research in aphasia: From neuroscience to neurorehabilitation. JSLHR, 51(1), S259-s275. Turkstra, L. S., Holland, A. L., & Bays, G. A. (2003). The neuroscience of recovery and rehabilitation: What have we learned from animal research? Archives of Physical Medicine and Rehabilitation, 84(4), 604-612. Gonzalez-Rothi, L. J. (2001). Neurophysiologic basis of rehabilitation. [Article]. Journal of Medical Speech- Language Pathology, 9(2), 117-127.