Neuroplasticity and Bilateral Cochlear Implantation Blake C. Papsin Karen A. Gordon
Cochlear Implant Clinical Team Blake Papsin Vicky Papaioannou Karen Gordon Sharon Cushing Gina Goulding Naureen Sohail Laurie MacDonald Patt Fuller Adrian James Mary Lynn Feness Pat Di Santos Nancy Greenwald-Hood Susan Druker Valerie Simard Rebecca Malcomson Joelene Huber Gillian Lieberman Stephanie Jewell
Cochlear Implant Research Team DIRECTORS Karen Gordon Blake Papsin Sharon Cushing RESEARCH COORDINATORS Stephanie Jewell Carmen McKnight GRADUATE STUDENTS Salima Jiwani Melissa Polonenko Nikolaus Wolter Morrison Steel Michael Deighton Sara Giannantonio Josh Gnanasegaram FUNDING CIHR SickKids Foundation POST-DOCTORAL FELLOWS Vijayalakshmi Easwar William Parkes Shazia Peer COLLABORATORS Local Sick Kids Bob Harrison Susan Blaser Adrian James Paolo Campisi Sam Doesburg Vicky Papaioannou Local - External Sandra Trehub Frank Russo International Robert Cowen Richard van Hoesel
Introduction evolution/plasticity genetic facultative feature extraction binaurality assembly of the auditory environment effort
Introduction evolution/plasticity genetic facultative feature extraction binaurality John Tyler (1790-1862) Teddy Roosevelt (1858-1919) Chester Arthur (1829-1886) Woodrow Wilson (1856-1924) assembly of the auditory environment effort
Evolution/Plasticity Starlings at Otmoor http://www.youtube.com/watch?v=xh-grocekbe (Dylan Winter)
Human = Communicators olfaction vision motor skill audition linguistic ability executive function
Feature Extraction pattern recognition learn rules fidelity experience consistency
SickKids Bilateral Experience Simultaneous implants n=198 Age at implant = 3.0 ± 3.5 yrs Sequen&al implants n=180 Age at 1st implant = 3.4 ± 3.1 yrs Age at 2 nd implant = 9.6 ± 4.7 yrs Inter- implant delay = 6.1 ± 3.9 yrs
Brainstem Asymmetry Simultaneous Sequential Gordon, et al., 2010
Studying Binaural Perception
Studying Binaural Perception Lateralization Index = (R-L)/(R+L) Wong et al. IEEE (2010)
Reorganization of Auditory Cortex Long Delay (> 2 years) * * * Left cortex Right cortex Short Delay (< 1.5 years) Simultaneous Normal Hearing Lateralization of auditory activity (%) * P<0.05 Gordon et al. Brain (2013)
Reorganization of Auditory Cortex Long Delay (> 2 years) * * * Left cortex Right cortex Short Delay (< 1.5 years) Simultaneous Normal Hearing Lateralization of auditory activity (%) * P<0.05 Gordon et al. Brain (2013)
Spatial Unmasking (noise at 0 ) vs. (noise at 90 )
Spatial Unmasking (noise at 0 ) vs. (noise at 90 )
Spatial Unmasking Spatial unmasking SNR (db) 11 10 9 8 7 6 5 4 3 2 1 0 Noise moved to 1st implanted ear Noise moved to 2nd implanted ear P=0.001 P>0.05 Sequential sequential Simultaneous simultaneous Normal normal Chadha et al., Otol NeuroOtol, 2011
Inter-Aural/Implant Level & Timing Differences Normal Response Rate 100 50 0 LeG +20 db +10 db 0 db - 10 db - 20 db Right 100 50 L 0 R L R Sequential Response Rate 100 50 0 CI2 +20 CU ILD Condi&on +10 CU 0 CU - 10 CU - 20 CU CI1 100 80 60 40 CI1 20 CI2 0 CI2 CI1 Simultaneous Response Rate 1 0.8 0.6 0.4 0.2 0 ILD Condi&on Left +20 CU +14 CU +10 CU +6 CU +2 CU 0-2 CU -6 CU -10 CU -14 CU Right L R 1 0.8 0.6 0.4 0.2 0 L R Intra-Aural/Implant Loudness Difference Condition Intra-Aural/Implant Timing Difference Condition
Inter-Aural/Implant Level & Timing Differences Normal Response Rate 100 50 0 LeG +20 db +10 db 0 db - 10 db - 20 db Right 100 50 L 0 R L R Sequential Response Rate 100 50 0 CI2 +20 CU ILD Condi&on +10 CU 0 CU - 10 CU - 20 CU CI1 100 80 60 40 CI1 20 CI2 0 CI2 CI1 Simultaneous Response Rate 1 0.8 0.6 0.4 0.2 0 ILD Condi&on Left +20 CU +14 CU +10 CU +6 CU +2 CU 0-2 CU -6 CU -10 CU -14 CU Right L R 1 0.8 0.6 0.4 0.2 0 L R Intra-Aural/Implant Loudness Difference Condition Intra-Aural/Implant Timing Difference Condition
Inter-Aural/Implant Level & Timing Differences 100 80 60 40 20 0 Sequential Month 9, n=29 CI2 20 10 0-10 -20 CI1 Rate of Right/CI1 Responses 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 Sequential * +1000 +400 0-400 -1000 Simultaneous Simultaneous (n=20) Sequential R CI1 only (n=10) Normal (n=16) CI2 weighted CI1 weighted left leading right leading Interaural Level Difference (CU) Gordon, Abbasalipour et al., in press Inter-aural/implant Timing Difference (µs)
Binaural Fusion Steel et. al., in press
Inter-Aural/Implant Level & Timing Differences and Fusion 1.0 0.8 0.6 0.4 0.2 0.0 * p<0.0001 Level Cues 0 T T+10 T+20 L/CI- 2 Level Changing (db/cu) Unilateral control NH Group CI Group ITD = 0 ms Electrode = 20 (n=24) (n=25) Propor=on of 1 Response 1.0 0.8 0.6 0.4 0.2 0.0 p<0.0001 * Timing Cues 24 2 1 0.4 0-0.4-1 - 2-24 ITD (ms) p<0.0001 * NH (n=24) Group (n=25) (Mean ILD = - 0.34 ± 0.9 db)
Increased Effort & Increased P2 Amplitude Increased reac=on =me - emo=ons P2 Amplitude in speech aler auditory training Reac=on Time (ms) 4000 3500 3000 2500 2000 1500 1000 500 0 Cochlear Implant Users (n=24) ** ** p<0.01 P1 Normal Hearing Peers N1 (n=23) P2 Auditory Auditory- Visual Hopyan et al. Child Neuropsychology Tremblay (2009) et al. Clinical Neurophysiology (2009)
P2 P2 Jiwani et al. Clinical Neurophysiology (2013) Gordon et al. Fron8ers in Auditory Cogni8ve Neuroscience (2013)
Additional Resources Recruited Right S=mula=on CI Experienced Normal Hearing Dipole Differences P1 - P1 N1 - N1 P2 - P2 Jiwani et al., Submi?ed
Plasticity/Novel Process? the auditory system makes full use of sensory data novel methods of data processing are employed. precisely because assembling correctly promotes survival