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NMDA Receptors in Motor Learning in Humans

NMDA Receptors in Motor Learning in Humans

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02082912
Enrollment
14
Registered
2014-03-10
Start date
2010-06-30
Completion date
2012-04-30
Last updated
2018-11-07

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Stroke

Brief summary

The purpose of this study is to focus on enhancing upper limb recovery in patients post-stroke by using robotic-assisted therapy in combination with a drug to improve learning new motor skills.

Detailed description

Disability after a stroke is common, leaving 65% of patients unable to use their affected hand in daily activities after 6 months. Frequently, these limitations can cause a decreased quality of life. The current standard for intense physical therapy most commonly consists of neurofacilitation techniques and/or task-specific training. Labor-intensive and costly therapy methods are critical barriers to achieving optimal functional outcomes in stroke survivors with motor impairments. Thus, there is a great need to find new ways to enhance the effectiveness of upper limb rehabilitation in patients following stroke. A promising approach to improving upper extremity motor function utilizing repetitive task practice (RTP) and behavioral shaping along with constraint of the less affected limb is constraint-induced movement therapy (CIMT). Two fundamental limitations of CIMT are the time necessary to deliver and oversee training and the excessive time in which the less affected limb must be constrained. RTP, in the context of CIMT appears to be effective in improving upper extremity motor function of patients with stroke. Alternative approaches such as robotic assisted therapy have been investigated. Recent evidence suggests that improvements in upper-extremity motor function, functional performance in daily tasks and quality of life are seen during a robotic-assisted physical therapy regimen. Activation of N-methyl-D-aspartate (NMDA) receptors is important for inducing various forms of synaptic plasticity. Application of D-cycloserine (a antibiotic for treating tuberculosis) can enhance certain models of plasticity, such as long-term potentiation. Pharmacologic strategies that enhance NMDA neurotransmission and working memory represent a promising adjuvant therapy in motor rehabilitation of patients after stroke. The researchers for this study have brought these observations together to generate a working hypothesis that D-cycloserine will enhance certain features of motor learning, information processing speed, episodic and working memory and that this effect can be coupled with physical therapy to facilitate retraining of patients to use impaired limbs to a greater extent and faster than they otherwise might be able to do. The researchers specifically hypothesize that motor (re)learning and cognition can be improved in people with post-stroke hemiparesis by increasing the excitability and synaptic activity of the motor cortex by combining D-cycloserine and robotic-assisted physical therapy. The purpose of this study is to understand the important factors in rehabilitation therapy that help improve arm function after stroke. This information may help to ultimately reduce disability and improve quality of life in patients with stroke.

Interventions

DRUGD-cycloserine

D-cycloserine 100mg PO twice weekly (Monday and Wednesday) for three weeks

OTHERPlacebo

Placebo pill PO twice weekly (Monday and Wednesday) for three weeks

DEVICEHandMentor Pro

The HandMentor Pro (Kinetic Muscles Inc.) is a robotic device that has recording electrodes. The device gives feedback during various activities requiring varying levels of wrist control. The main goal of the hand robot is to improve active range of motion about the wrist and fingers and wrist control. The robotic therapy will be done over 3 consecutive weeks for 2 hours each session (days 1, 3, 5, 8, 10, 12, 15, 17 and 19, for 18 hours total).

Sponsors

Emory University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender
ALL
Age
18 Years to 95 Years
Healthy volunteers
No

Inclusion criteria

* between the ages of 18 and 95 years * of either sex * of diverse ethnic background * have experienced a single unilateral hemispheric or brainstem stroke 3 or more months prior * if have experienced more than one stroke, will be accepted only if all strokes are on the same side of the brain, there is no history of a clinical ischemic or hemorrhagic event affecting the other hemisphere, and there is no CT or MRI evidence of more than one a lacune or minor ischemic demyelination affecting the other hemisphere. * active motions of the wrist and hand: 10 of wrist extension from a relaxed flexed position; 10 of extension of any two digits at any joint, and 10 of thumb extension at either joint. All active motions must be repeated 3 times within one minute. * passive range of motion: 90 of flexion and abduction and 45 external and internal rotation at the shoulder; 45 elbow supination and pronation; elbow extension limited by no more than 30; wrist extension to at least neutral; and digit extension limited by no more than 30. * participants will not be required to exhibit any active shoulder or elbow motion * ability to sit independently for at least 2 minutes * Mini Mental Status Examination score greater than 24 * Motor Activity Log score less than 3 * Prospective participants who qualify but who have profound postural instability will undergo the intervention while walking with contact guarding or, when feasible, using their leg and more involved arm to propel a wheelchair. * must have a score below 16 on the Center for Epidemiologic Studies Depression Scale * must receive a score greater than 25 on the Folstein Mini Mental State Exam.

Exclusion criteria

* any history of more than minor head trauma, subarachnoid hemorrhage, dementia or any other neurodegenerative disease, multiple sclerosis, HIV infection, drug or alcohol abuse, serious medical illness, schizophrenia, major refractory depression * insufficient cardiopulmonary function to participate in low-intensity sustained upper extremity exercise * severe visual impairment * pregnancy * breast feeding * participation in intensive physical therapy within the prior 12 months * inability to understand the potential risks and benefits of the study, personally provide informed consent, and understand and cooperate with treatment * participating in other upper extremity rehabilitation, clinical or experimental, during the course of this trial. * a score of less than 24 on the Folstein Mini-Mental State Exam * a score of less than10 on the Boston Naming Test * a first stroke less than 3 months or more than 48 months prior to the initiation of therapeutic intervention * less than 18 years old * clinical judgment of excessive frailty or lack of stamina * serious uncontrolled medical conditions * excessive pain in any joint of the more affected extremity that could limit ability to cooperate with the intervention * passive range of motion less than 45 degrees for: abduction, flexion or external rotation at shoulder, or pronation of forearm * greater than 30 degrees flexion contracture at any finger joint * unable to stand independently for 2 min., transfer independently to and from the toilet or perform sit-to-stand * current participation in other pharmacological or physical intervention studies, or have received injections of anti-spasticity drugs into upper extremity musculature within the past 3 months, or wish to have drugs injected in the foreseeable future * receiving any anti-spasticity drugs orally at the time of expected participation * received phenol injections less than 12 months prior to receiving therapy * contemplating a move from proximity to the treatment site in less than 6 months from the randomization date.

Design outcomes

Primary

MeasureTime frameDescription
Grip Strength of Affected HandBaseline, Day 30Hand-grip strength was assessed using the whole hand and was defined as the average of 3 trials using a calibrated Jamar dynamometer (Jamar Dynamometer, Asimow Engineering Co., Santa Monica, CA), with the elbow flexed to 90º and the forearm in a neutral position. This is the standardized method for measuring hand-grip strength with a Jamar dynamometer recommended by the American Society of Hand Therapists. An increase in values means that grip strength is improving.

Secondary

MeasureTime frameDescription
Percentage of Stroke Impact Scale (SIS) Categories Meeting Change CriteriaBaseline, Day 30The percentages of Stroke Impact Scale (SIS) physical domain categories meeting criteria for Minimal Clinically Important Difference (MCID) are presented here. The SIS has 59 items in 8 domains of function where respondents rate their degree of difficulty on a 5-point scale, plus a 9th category for stroke recovery (one item, scored from 0 to 100). Scores for each domain are generated so that total scores for each domain range from 0 - 100, where higher scores indicate less difficulty and more recovery. A change of more than 4.5 to 17.8 for the domains was considered a MCID. A higher percentage of SIS categories meeting the MCID criteria indicates increased improvement in that study arm.
Center for Epidemiologic Studies Depression (CES-D) Scale ScoreBaseline, Day 30Depressive symptoms were assessed with the Center for Epidemiologic Studies Depression (CES-D) Scale. The CES-S has 20 items rated on a scale of 0 to 3. Total scores range from 0 to 60 with higher scores indicating more depressive symptoms, and a score of 16 or above indicates depression. Baseline scores are presented in the Outcome Measure Data Table and the impact of the study arm at Day 30 is presented in the statistical analysis section.
Display Enhanced Testing for Concussions and Mild Traumatic Brain Injury (mTBI) (DETECT) System ScoreBaseline, Day 30Using a computer, helmet with heads-up-display, headphones with audio inputs, and an input unit with two buttons (Yes and No), the DETECT system combines an immersive environment with neuropsychological tests to assess mTBI. The DETECT software consists of a series of tests evaluating information processing speed, episodic memory, and working memory. Performance is scored based on response type (correct, incorrect, and missing) and response time. Test results are displayed using an internal algorithm that is based on the probability of impairment. Mean baseline z-scores are presented in the Outcome Measure Data Table and the impact of the study arm at Day 30 is presented in the statistical analysis section. A z-score of 0 represents a healthy individual; scores above 0 are the number of standard deviations above the mean, indicating more errors, taking more time, and thus having a higher probability of mild cognitive impairment.
Number of Blocks Moved During the Box and Block Test (BBT) of Affected ArmBaseline, Day 30Change in functional motor task performance of the arm affected by the stroke was assessed with the Box and Block Test (BBT). The BBT involves dexterous manipulation of objects and voluntary motor control, which improves with upper limb recovery following stroke. The number of blocks moved within 60 seconds are counted. Baseline scores of the mean number of blocks moved are presented in the Outcome Measure Data Table and the impact of the study arm at Day 30 is presented in the statistical analysis section.

Countries

United States

Participant flow

Recruitment details

Participants were recruited from the Center for Rehabilitation Medicine at Emory University in Atlanta, Georgia. Enrollment of participants began in June 2010 and study participation ended in April 2012.

Pre-assignment details

A total of 124 patients were screened and of these 14 met enrollment criteria and consented to participate in the study.

Participants by arm

ArmCount
D-cycloserine
Participants taking D-cycloserine and using the HandMentor Pro for robotic therapy
7
Placebo
Participants taking a placebo pill and using the HandMentor Pro for robotic therapy
6
Total13

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyPhysician Decision01

Baseline characteristics

CharacteristicD-cycloserineTotalPlacebo
Age, Continuous57.7 years
STANDARD_DEVIATION 7.3
55.8 years
STANDARD_DEVIATION 13.1
53.7 years
STANDARD_DEVIATION 18.4
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Black or African American
6 Participants10 Participants4 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
White
1 Participants3 Participants2 Participants
Region of Enrollment
United States
7 Participants13 Participants6 Participants
Sex: Female, Male
Female
7 Participants10 Participants3 Participants
Sex: Female, Male
Male
0 Participants3 Participants3 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 70 / 7
other
Total, other adverse events
0 / 70 / 7
serious
Total, serious adverse events
0 / 70 / 7

Outcome results

Primary

Grip Strength of Affected Hand

Hand-grip strength was assessed using the whole hand and was defined as the average of 3 trials using a calibrated Jamar dynamometer (Jamar Dynamometer, Asimow Engineering Co., Santa Monica, CA), with the elbow flexed to 90º and the forearm in a neutral position. This is the standardized method for measuring hand-grip strength with a Jamar dynamometer recommended by the American Society of Hand Therapists. An increase in values means that grip strength is improving.

Time frame: Baseline, Day 30

Population: Participants completing the study are included in this analysis.

ArmMeasureGroupValue (MEAN)Dispersion
D-cycloserineGrip Strength of Affected HandBaseline3.95 NewtonStandard Deviation 2.96
D-cycloserineGrip Strength of Affected HandDay 304.90 NewtonStandard Deviation 3.56
PlaceboGrip Strength of Affected HandBaseline5.72 NewtonStandard Deviation 3.98
PlaceboGrip Strength of Affected HandDay 308.44 NewtonStandard Deviation 4.9
Secondary

Center for Epidemiologic Studies Depression (CES-D) Scale Score

Depressive symptoms were assessed with the Center for Epidemiologic Studies Depression (CES-D) Scale. The CES-S has 20 items rated on a scale of 0 to 3. Total scores range from 0 to 60 with higher scores indicating more depressive symptoms, and a score of 16 or above indicates depression. Baseline scores are presented in the Outcome Measure Data Table and the impact of the study arm at Day 30 is presented in the statistical analysis section.

Time frame: Baseline, Day 30

Population: Participants completing the study are included in this analysis.

ArmMeasureValue (MEAN)Dispersion
D-cycloserineCenter for Epidemiologic Studies Depression (CES-D) Scale Score15.1 units on a scaleStandard Deviation 6.5
PlaceboCenter for Epidemiologic Studies Depression (CES-D) Scale Score9.2 units on a scaleStandard Deviation 8.8
Comparison: Values represent the time x treatment group interaction.p-value: 0.651ANOVA
Secondary

Display Enhanced Testing for Concussions and Mild Traumatic Brain Injury (mTBI) (DETECT) System Score

Using a computer, helmet with heads-up-display, headphones with audio inputs, and an input unit with two buttons (Yes and No), the DETECT system combines an immersive environment with neuropsychological tests to assess mTBI. The DETECT software consists of a series of tests evaluating information processing speed, episodic memory, and working memory. Performance is scored based on response type (correct, incorrect, and missing) and response time. Test results are displayed using an internal algorithm that is based on the probability of impairment. Mean baseline z-scores are presented in the Outcome Measure Data Table and the impact of the study arm at Day 30 is presented in the statistical analysis section. A z-score of 0 represents a healthy individual; scores above 0 are the number of standard deviations above the mean, indicating more errors, taking more time, and thus having a higher probability of mild cognitive impairment.

Time frame: Baseline, Day 30

Population: Participants with complete information for the DETECT measurement are included in this analysis. Two participants had missing values dues to technical issues with the instrument.

ArmMeasureValue (MEAN)Dispersion
D-cycloserineDisplay Enhanced Testing for Concussions and Mild Traumatic Brain Injury (mTBI) (DETECT) System Score10.2 z-scoreStandard Deviation 0
PlaceboDisplay Enhanced Testing for Concussions and Mild Traumatic Brain Injury (mTBI) (DETECT) System Score10.1 z-scoreStandard Deviation 0.1
Comparison: Values represent the time x treatment group interaction.p-value: 0.447ANOVA
Secondary

Number of Blocks Moved During the Box and Block Test (BBT) of Affected Arm

Change in functional motor task performance of the arm affected by the stroke was assessed with the Box and Block Test (BBT). The BBT involves dexterous manipulation of objects and voluntary motor control, which improves with upper limb recovery following stroke. The number of blocks moved within 60 seconds are counted. Baseline scores of the mean number of blocks moved are presented in the Outcome Measure Data Table and the impact of the study arm at Day 30 is presented in the statistical analysis section.

Time frame: Baseline, Day 30

Population: Participants completing the study are included in this analysis.

ArmMeasureValue (MEAN)Dispersion
D-cycloserineNumber of Blocks Moved During the Box and Block Test (BBT) of Affected Arm9.7 blocks per minuteStandard Deviation 7.9
PlaceboNumber of Blocks Moved During the Box and Block Test (BBT) of Affected Arm9.6 blocks per minuteStandard Deviation 6.2
Comparison: Values represent the time x treatment group interaction.p-value: 0.471ANOVA
Secondary

Percentage of Stroke Impact Scale (SIS) Categories Meeting Change Criteria

The percentages of Stroke Impact Scale (SIS) physical domain categories meeting criteria for Minimal Clinically Important Difference (MCID) are presented here. The SIS has 59 items in 8 domains of function where respondents rate their degree of difficulty on a 5-point scale, plus a 9th category for stroke recovery (one item, scored from 0 to 100). Scores for each domain are generated so that total scores for each domain range from 0 - 100, where higher scores indicate less difficulty and more recovery. A change of more than 4.5 to 17.8 for the domains was considered a MCID. A higher percentage of SIS categories meeting the MCID criteria indicates increased improvement in that study arm.

Time frame: Baseline, Day 30

Population: Participants completing the study are included in this analysis.

ArmMeasureValue (NUMBER)
D-cycloserinePercentage of Stroke Impact Scale (SIS) Categories Meeting Change Criteria44.4 percentage of category scores
PlaceboPercentage of Stroke Impact Scale (SIS) Categories Meeting Change Criteria24.1 percentage of category scores

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026