Cortical stimulation improves skilled forelimb use following a focal ischemic infarct in the rat

Teskey, G. Campbell; Flynn, Corey; Goertzen, Crystal D.; Monfils, Marie‐H.; Young, Nicole A.

doi:10.1179/016164103771953871

Cited by 151 publications

(130 citation statements)

References 24 publications

Supporting

Mentioning

120

Contrasting

Unclassified

Order By: Relevance

“…This finding is in agreement with previous data indicating that monopolar or bipolar CS delivered at frequencies between 50 and 100 Hz and at 40 to 70 % of movement thresholds greatly improves reaching performance compared to unstimulated reach trained controls (Adkins-Muir and Jones, 2003;Kleim et al, 2003b;Plautz et al, 2003;Teskey et al, 2003;Adkins et al, 2006b) and rats receiving 250 Hz CS during training (Adkins-Muir and Jones, 2003). CS and motor training was initiated 2 weeks after the infarcts in the present study, but it is also effective when delivered at earlier (Kleim et al, 2003b;Teskey et al, 2003) and later (Plautz et al, 2003) time points. The present results extend the previous behavioral findings by indicating that CS also partially improves abnormalities in the movements used to perform the reaching task.…”

Section: Motor Cortical Stimulation Improves Reaching Function In Thesupporting

confidence: 93%

“…Nevertheless, movement threshold were similar to a previous study using epidural electrodes and between groups. Also consistent with previous findings (Adkins-Muir and Jones, 2003;Teskey et al, 2003), movement thresholds declined over days (F(2,84) = 4.19, p = 0.02). The severely impaired group tended to show less of a decline in movement threshold current levels, but there was no significant difference between groups (p = 0.81) or group by day interaction effect (p = 0.09).…”

Section: Nih-pa Author Manuscriptsupporting

confidence: 92%

“…The neural mechanisms of these functional effects are unknown, but we hypothesize that CS recruits neurons that may otherwise be insufficiently activated during task performance and that this enables activitydependent synaptic plasticity that mediates recovery of skilled movements in the impaired forelimb. Consistent with this possibility, CS-induced improvements in reaching success coincide with neuroplastic changes in the stimulated region of the SMC, including increased surface density of layer V dendritic processes (Adkins-Muir and Jones, 2003), expansion of movement representations detected using intracortical microstimulation mapping (in rats: Kleim et al, 2003b;in monkeys: Plautz et al, 2003) and enlargement of the polysynaptic component of motor cortical evoked potentials (Teskey et al, 2003) compared to animals receiving rehabilitation alone. Because plasticity of synaptic connectivity is thought to underlie motor learning and re-learning (Monfils et al, 2005), a major purpose of the present study was to directly determine whether training combined with CS induces greater structural plasticity of synapses in remaining motor cortex than training alone.…”

mentioning

confidence: 80%

“…Recent studies in humans indicate that stimulation of select cortical regions might be used to improve the efficacy of rehabilitative training (Brown and Pilitsis, 2006;Hummel and Cohen, 2006;Pascual-Leone, 2006). In support of this possibility, recent studies in monkeys (Plautz et al, 2003) and rats (Adkins-Muir and Jones, 2003;Kleim et al, 2003b;Teskey et al, 2003; Adkins et al, 2006b) with infarcts of the sensorimotor cortex (SMC) indicate that the efficacy of rehabilitation can be greatly enhanced by coupling it with cortical stimulation (CS) of the peri-infarct region. In this approach, as animals are undergoing daily training on a skilled reaching task, subthreshold (to evoke movements) current is passed through electrodes positioned over remaining motor cortex.…”

Section: Nih Public Access Author Manuscriptmentioning

confidence: 99%

“…Previously, CS combined with post-lesion rehabilitative training was found to increase periinfarct dendritic density (Adkins-Muir and Jones, 2003) and to induce functional alterations in the motor cortex, as revealed by expanded forelimb motor maps (Kleim et al, 2003b;Plautz et al, 2003) and neural potentiation, revealed as an increase in the late-component of motor evoked potentials (Teskey et al, 2003) compared to unstimulated rehabilitation-only controls. The present finding of CS induced increases in synaptic density provides direct support that CS influences synaptic connectivity in the motor cortex and is consistent with the general hypothesis that positive modulation of synaptic plasticity mediates the behavioral improvements resulting from CS.…”

Section: Cortical Stimulation Promotes Synaptic Changes Which Are Cormentioning

confidence: 99%

See 4 more Smart Citations

Motor cortical stimulation promotes synaptic plasticity and behavioral improvements following sensorimotor cortex lesions

Adkins

Hsu

Jones

2008

Experimental Neurology

120

133

View full text Add to dashboard Cite

Cortical stimulation (CS) as a means to modulate regional activity and excitability in cortex is emerging as a promising approach for facilitating rehabilitative interventions after brain damage, including stroke. In this study, we investigated whether CS-induced functional improvements are linked with synaptic plasticity in peri-infarct cortex and vary with the severity of impairments. Adult rats that were proficient in skilled reaching received subtotal unilateral ischemic sensorimotor cortex (SMC) lesions and implantation of chronic epidural electrodes over remaining motor cortex. Based on the initial magnitude of reaching deficits, rats were divided into severely and moderately impaired subgroups. Beginning two weeks post-surgery, rats received 100 Hz cathodal CS at 50% of movement thresholds or no-stimulation control procedures (NoCS) during 18 days of rehabilitative training on a reaching task. Stereological electron microscopy methods were used to quantify axodendritic synapse subtypes in motor cortical layer V underlying the electrode. In moderately, but not severely impaired rats, CS significantly enhanced recovery of reaching success. Sensitive movement analyses revealed that CS partially normalized reaching movements in both impairment subgroups compared to NoCS. Additionally, both CS subgroups had significantly greater density of axodendritic synapses and moderately impaired CS rats had increases in presumed efficacious synapse subtypes (perforated and multiple synapses) in stimulated cortex compared to NoCS. Synaptic density was positively correlated with postrehabilitation reaching success. In addition to providing further support that CS can promote functional recovery, these findings suggest that CS-induced functional improvements may be mediated by synaptic structural plasticity in stimulated cortex.Keywords motor rehabilitation; skilled reaching; synaptic plasticity; perforated synapses; multisynaptic boutons; stroke Motor impairments are among the most common disabilities caused by stroke (Thom et al., 2006). Motor rehabilitative training can reduce these impairments but it is often insufficient * Corresponding author. The University of Texas, 1 University Station A8000, Austin, TX 78712. Phone: +1 512 475-7763, Fax: +1 512 475-7765, dladkins@mail.utexas.edu. ‡ D.L.A and J.E.H. contributed equally to this work.Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. NIH Public Access Author ManuscriptExp Neurol. Author manuscript; available in PMC 2011 January 10. to restore normal levels of function (Duncan et al., 2000;Dobkin, 2004). Recent studies in ...

show abstract