Y P O C T O N O D E Mar Cortes, MD S Assistant Professor, - - PowerPoint PPT Presentation

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Jan 18, 2023 237 likes •443 views

Y P O C T O N O D E Mar Cortes, MD S Assistant Professor, Rehabilitation & Human Performance Department Co-Director, Abilities Research Center A Icahn School of Medicine at Mount Sinai, New York mar.cortes@mountsinai.org E L P

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Mar Cortes, MD Assistant Professor, Rehabilitation & Human Performance Department Co-Director, Abilities Research Center Icahn School of Medicine at Mount Sinai, New York mar.cortes@mountsinai.org

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How can we induce plastic changes at the brain level? Paired Associative Stimulation (PAS)

Or when the peripheral stimulation meets the MEP

How can we induce plastic changes at the spinal level? Spinal Associative Stimulation (SAS)

Or when the central stimulation meets the H-reflex

Investigating Hebbian principles of neural plasticity in humans "Cells that fire together, wire together"

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How do we measure cortical excitability? The MEP

EMG Instrument Magnetic Stimulator

TMS

STIMULUS

MEP

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PAS protocol

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The increase of cortical excitability (MEP amplitude) was

dependent on the synchronous timing between the afferent and the magnetic stimulation

Plasticity induced by PAS

– 1. evolved rapidly (within 30 min), – 2. was persistent (minimum duration 30-60 min) yet reversible, and – 3. was topographically specific

properties signature of associative long-term potentiation (LTP). PAS summary:

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How do we measure spinal excitability? The H-REFLEX

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SAS protocol

90 paired stimuli PNS TMS 20ms 0.1 Hz 900 10 40 30 20 50 890 sec

PRE POST INTERVENTION (15 min) H-Reflex RC H-Reflex RC

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Peripheral stimulation of somatosensory afferents conditioned by low frequency TMS, increases spinal excitability

Cortes et al, Clin Neurophys, 2011

Electrical Stimulator Magnetic

Stimulator

Ia afferents fibers Efferent motor fibers Dorsal root (sensory) Ventral root (motor)

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SAS experimental set up

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Pharmacology of PAS

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Pharmacology of PAS

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PAS clinical applications

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PAS clinical applications

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Modified PAS protocols

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