Repetition Priming and Anomia: An Investigation of Stimulus Dosage Catherine A. Off, Ph.C., CCC-SLP 1 ; Holly Kavalier, B.A. 1 ; Margaret A. Rogers, Ph.D. 1, 2 ; CCC-SLP; Kristie Spencer, Ph.D., CCC-SLP 1 Participants 1 Department of Speech & Hearing Sciences, University of Washington, Seattle, Washington; 2 American Speech-Language-Hearing Association, Rockville, MD Design Single Subject ABA Design with Replication across 4 Individuals with Aphasia and 1 Non-Brain-Injured, Age- and Gender-Matched Control Probe Sessions: 40 Trained Items; 20 Untrained Items; Balanced for Syllable Length and Word Frequency Training Sessions: 40 Trained Items; 20 1-Trials/Session; 20 4-Trials/Session; Balanced for Syllable Length and Word Frequency Dependent Variables: Response Accuracy (Live and Audio-Recorded Samples) and Response Time (Measured by E-Prime - milliseconds) Reliability: All Probe Sessions Transcribed and Coded for both Accuracy and Error Type by Independent Judges Blinded to Training Variables Delivery Schedule SESSION # Baseline Probes Training Sessions Training Probes Stimulus Generalization Maintenance Training Sessions Characteristics of Repetition Priming (Healthy Adults) Increases Reaction Time and Improves Accuracy on Subsequent Trials Persistent Across Time (Cave, 1997) Sensitive to # of Repetitions (Brown, Jones, & Mitchell, 1988; Reber, Gitelman, Parrish, & Mesulam, 2004 ) Item Specific (Brown, Jones, & Mitchell, 1996) Generalizes to Alternate Exemplars (Koutstaal, Wagner, Rotte et al., 2001) Repetition Matters A102A103A104A106CONTROL # Training Sessions # Exposures Naming Attempts w/o support 300; ; ; ; ; 720 Naming attempts w/ support 300; ; ; ; ; 720 Total Naming Attempts600; ; ; ; ; 1440 Integrating Principles of Neuroplasticity into clinical practice is necessary to optimize rehabilitative outcomes. Repetition is fundamental to skill learning and re-learning Motor learning, at both behavioral and neural levels, requires hundreds of trials The current investigation examines the application of repetition to improve naming performance in individuals with chronic aphasia. Though repetition is a ubiquitous component of anomia treatment protocols, and may be one of the most potent sources of change, systematic investigation of the influence of stimulus dosage on naming performance has yet to be reported, particularly with respect to the acquisition and maintenance of trained items, generalization to untrained items and generalization to alternate exemplars of trained items. Is Repetition Priming:Independent Variables Persistent across Time? Immediate vs. Delayed probes; Baseline vs. Maintenance Probes (6 weeks after final training session) Sensitive to # of Exposures/Session?1 vs. 4 Trials per Training Session Item Specific?Trained vs. Untrained Stimuli Generalize to Alternate Exemplars?Stimulus Generalization Probes Stimulus Dosage by Participant Experimental Questions and Independent Variables X * X * coffee Response Time Results (ms) Accuracy Results A102A103A104A106Control Baseline Probes Overall Last Two Training Probes Trained Untrained Trial Trials Maintenance Probes Trained pending Untrained pending 1 Trial pending 4 Trials pending Discussion Is Repetition Priming:Individuals with AphasiaAge- & Gender-Matched Control (Matched A103) Persistent across Time? Response Accuracy: Yes – A102 & A103 maintained improved response accuracy for trained items 6 weeks after last training session; awaiting results from A104 & A106; stronger priming effects for immediate post-training probes vs. delayed probes Response Time: Yes for A102; A103 demonstrated a RT for accuracy trade-off Reaction Time: Pending Maintenance Probes Sensitive to # of Exposures/Session? Response Accuracy: Inconclusive – may depend on underlying impairment or time post onset Response Time: Inconclusive Reaction Time: Yes – 7 ms difference between 4 trials per session and 1 trial per sessions Item Specific? Response Accuracy: No evidence of generalization to untrained items presented during experiment; however, note positive changes of BNT and PALPA scores pre/post Response Time: Yes for A102, A104 & A106: trained items were responded to faster than untrained items; A103 demonstrated a RT for accuracy trade-off Reaction Time: Yes – No evidence of generalization from trained to untrained items (143 ms difference between trained and untrained items) Generalize to Alternate Exemplars? Response Accuracy: Inconclusive, but no obvious trends towards stimulus generalization Response Time: Yes for A102, A106; No for A103, A104 Reaction Time: Yes – 165 ms difference between first stimulus generalization probe to the last stimulus generalization probe A102 Trained vs. Untrained 1 vs. 4 Trials Stimulus Generalization A103 A104 A106 d=7.30 d=4.19 pending * d=Busk & Serlin’s d A102 A104A106 Age GenderFemale Time post CVA6 months3.5 yrs1.5 yrs8 months Type of CVAEmbolicHemorrhagic Embolic/Thrombolic Location of CVAL MCA L Temporal lobe L Basal Ganglia L MCA; L frontal lobe, ant. insula region L frontal operculum Cognitive- Linguistic Battery PrePostPrePostPrePostPrePost WAB pending BNT10/6014/605/6010/6027/6024/6012/60pending PALPA25/6043/6026/6038/6050/6052/6035/60pending Cognitive- Linguistic Battery Administered only once at study onset. Data used for inclusionary & descriptive purposes. Pyramids & Palms 38/5248/52 49/52 ABANo apraxia DNT - Complicated by conduction aphasia RCBA29/3030/30 Visual Agnosia10/10 Raven’s18/3636/3620/3618/36 BDI-II3/6310/6318/637/63