Delaina Walker-Batson

Amphetamine paired with physical therapy accelerates motor recovery after stroke : further evidence

BACKGROUND AND PURPOSE In animal models of brain injury, administration of numerous pharmaceuticals is reported to facilitate functional recovery. However, only drugs that increase the release of norepinephrine have been shown to promote recovery when administered late (days to weeks) after injury. To determine whether these findings were applicable to humans, we administered the norepinephrine stimulant dextroamphetamine, paired with physical therapy, to hemiplegic stroke patients. METHODS Ten hemiplegic patients who suffered an acute ischemic infarction were entered between days 16 and 30 after onset and randomly assigned to receive either 10 mg of dextroamphetamine or a placebo orally every fourth day for 10 sessions paired with physical therapy. The Fugl-Meyer Motor Scale was used at baseline, within each session, and for 12 months after onset as the dependent measure. Confounding medications such as alpha-adrenergic antagonists or agonists were excluded in all subjects. RESULTS Although there were no differences between the groups at baseline (P = .599), there was a significant (P = .047) difference between the groups when the drug had been discontinued for 1 week and at the 12-month follow-up visit (P = .047). CONCLUSIONS Administration of dextroamphetamine paired with physical therapy increased the rate and extent of motor recovery in a small group of hemiplegic stroke patients. These data support and extend previous findings of the facilitatory aspects of certain types of drugs on recovery from brain injury. The use of neuromodulation may allow the nervous system to adapt previously unused or alternative pathways to relevant external input.

Use of amphetamine in the treatment of aphasia

The effects of d-amphetamine on the recovery of aphasia following stroke was examined in 6 patients. Patients entered the study between 10 and 30 days post onset and were followed for 3 months. The Porch Index of Communicative Ability was used to project a 6 month recovery score. By 3 months post onset, 5 of the 6 patients obtained scores in excess of 100% of the 6 month projections.

Effects of Repetitive Electrical Stimulation to Treat Sensory Loss in Persons Poststroke

UNLABELLED Smith PS, Dinse HR, Kalisch T, Johnson M, Walker-Batson D. Effects of repetitive electrical stimulation to treat sensory loss in persons poststroke. OBJECTIVE To explore the effectiveness of repetitive electrical stimulation referred to here as tactile coactivation and to improve sensory discrimination and function in the most involved hand of a person recovering from stroke. DESIGN Pre-experimental 1-group (n=4) design with multiple measures. SETTING Outpatient stroke treatment center. PARTICIPANTS Subjects with 6 months or longer poststroke with self-reported sensory loss and a mild motor impairment in the most involved hand. INTERVENTION Electrical stimulation (coactivation) of the fingers of the involved hand for 90 minutes 4 days a week for 6 weeks. MAIN OUTCOME MEASURES Primary-dependent measures included touch threshold, tactile acuity, haptic object recognition, motor tapping task, pegboard activities, and functional tasks from the Wolf Motor Function Test. RESULTS Posttreatment assessments revealed improvements in sensory discrimination and motor task performance in all subjects in varying degrees; these results held 4 weeks posttreatment. CONCLUSIONS The type of repetitive electrical stimulation or tactile coactivation used in this study has not been explored previously in subjects with sensory loss caused by stroke. The results of this pilot study suggest that coactivation may have the potential to be a useful therapeutic modality for this population.

Functional Imaging and Related Techniques: An Introduction for Rehabilitation Researchers

Over the past 25 years, techniques to image brain structure and function have offered investigators in the cognitive neurosciences and related fields unprecedented opportunities to study how human brain systems work and are connected. Indeed, the number of peer-reviewed research articles using these techniques has grown at an exponential rate during this period. Inevitably, investigators have become interested in mapping neuroplastic changes that support learning and memory using functional neuroimaging, and concomitantly, rehabilitation researchers have become interested in mapping changes in brain systems responsible for treatment effects during the rehabilitation of patients with stroke, traumatic brain injury, and other brain injury or disease. This new rehabilitation research and development arena is important because a greater understanding of how and why brain systems remap in the service of rehabilitation will lead to the development of better treatments. At the same time that functional neuroimaging methods have been developed, new structural neuroimaging techniques also have been added to the tool box of rehabilitation researchers. For example, diffusion tensor imaging (DTI) and related magnetic resonance (MR) techniques offer the ability to assess human white matter pathways in vivo. Not only can these techniques be used to estimate the integrity of a given volume of white matter, but they also can be used to trace fiber tracts within the brain. This latter development is exciting because most of what we know (or at least thought we knew) about the connections of the human cortex has actually come from research on nonhuman primates, leaving questions especially about the phylogenetically newer portions of the cortex. In the rehabilitation arena, a better understanding of how the brain’s connections are damaged could help us to predict what treatments are best for different research subjects and, eventually, might be useful in selecting the best treatment strategies for individual patients. Because the newer functional and structural neuroimaging techniques have enormous implications for rehabilitation research and development, it is highly desirable that rehabilitation researchers be able to evaluate the usefulness of the techniques for rehabilitation research and that the consumers of rehabilitation research (i.e., clinicians and researchers) be able to evaluate research findings that have applied the techniques. The purpose of this article is to discuss functional and structural imaging techniques used in rehabilitation research. We will not cover routine clinical MR or x-ray computerized tomography (CT) images. Rather, we will concentrate on a variety of techniques used most frequently, though not necessarily exclusively, in research settings. The article will consist of two main sections: (1) Because of the extraordinary versatility or MR techniques, the large number of MR techniques will be discussed first. (2) Subsequently, other functional neuroimaging techniques will be discussed, including: Positron Emission Tomography (PET), Magnetoencephalography/Magnetic Source Imaging (MEG/MSI), Near Infrared Spectroscopy (NIRS), Transcranial Magnetic Stimulation (TMS), and Electroencephalography/Evoked Potentials (EEG/EPs). For each imaging modality, we will give a brief explanation of the modality, its uses/potential uses in rehabilitation research, its strengths and limitations, and an example of research in the area.

The effect of fast speech rate on stuttering frequency during delayed auditory feedback

UNLABELLED Delayed auditory feedback (DAF) has been documented to improve fluency in those who stutter. The increased fluency has been attributed to the slowed speech rate induced by DAF, but recent experiments have suggested that increasing the speech rate may also decrease stuttering under DAF. This investigation described the effect of combining a fast speech rate and DAF on the fluency of four people who stutter. Fluency of the two mildly dysfluent subjects was the same for both no DAF and DAF conditions at normal and at fast oral reading rates. In contrast, the two severely dysfluent subjects improved in fluency from the no DAF to the DAF conditions. They were found to be dysfluent at both normal and fast oral reading rates without DAF. The results of the study point to the need for further research on the relationship between speech rate and stuttering frequency under conditions of DAF and no DAF. EDUCATIONAL OBJECTIVES Readers will learn about and be able to describe how the frequency of stuttering is affected by: (1) speech rates; (2) DAF; and (3) how stuttering severity influences such effects.

A long-term follow-up case study of crossed aphasia assessed by single-photon emission tomography (SPECT), language, and neuropsychological testing

A 65-year-old man with well-defined crossed aphasia secondary to right cerebral infarction 10 years previously was studied for current language and cognitive abilities and regional cerebral blood flow (rCBF) during cognitive activation measured by single-photon emission tomography (SPECT). Reversed hemispheric lateralization was demonstrated by qualitative aspects of the patients constructional deficits, dominant parietal lobe signs, and absence of the neglect syndrome. Language activation procedures during SPECT produced focal increases in rCBF to both frontal lobes with a phoneme detection task and to right temporal and parietal lobes with a math task. The authors stress the complexities of assessing brain/language mechanisms in vivo and demonstrate variabilities in rCBF during language activation dependent on task selection.

Amphetamine and other pharmacological agents in human and animal studies of recovery from stroke.

Neuromodulation with pharmacological agents, including drugs of abuse such as amphetamine, when paired with behavioral experience, has been shown to positively modify outcomes in animal models of stroke. A number of clinical studies have tested the efficacy of a variety of drugs to enhance recovery of language deficit post-stroke. The purpose of this paper is to: (1) present pertinent animal studies supporting the use of dextro-amphetamine sulfate (AMPH) to enhance recovery after experimental lesions with emphasis on the importance of learning dependent activity for lasting recovery; (2) briefly review neuropharmacological explorations in the treatment of aphasia; (3) present a pilot study in aphasia exploring a drug combination of AMPH and donepezil hydrochloride paired with behavioral treatment to facilitate recovery; and (4) conclude with comments regarding the role of adjunctive pharmacotherapy in the rehabilitation of aphasia, particularly AMPH.

Evidence from Basic Neuroscience and Human Studies of Pharmacologic Therapy

Publisher Summary Aphasia is a major symptom of stroke and shares common neurophysiological and neurochemical features with other stroke consequences. Physiologic events following brain injury complicate the timing for administration of various agents. Drugs that are effective in the very acute or subacute period following injury may be ineffective or even detrimental at later recovery periods. Treatment approaches can be either adaptive or maladaptive. Pharmacological treatment as an adjunct to traditional approaches to the treatment of stroke is not a new idea. Enhanced recovery from hemiplegia after occlusive stroke has been reported using noradrenergic agonists paired with physical therapy. Small pilot studies have explored drugs, such as amphetamine; recovery from hemiplegia after occlusive stroke has been reported using noradrenergic agonists paired with physical therapy. Several laboratories are exploring post-stroke manipulations of brain plasticity following experimental injury in terms of the timing and type of intervention. This chapter reviews theories of neuroplasticity thought to underlie behavioral recovery, animal recovery studies that may have importance in the design of rehabilitation practice, and data from humans on pharmacologic therapy in the treatment of hemiplegia and aphasia.

Symbolic and affective non-verbal deficits in left- and right-hemisphere injured adults

Abstract Two groups of unilaterally brain-damaged adults and a normal control group were compared on tasks of symbolic (pantomime) and affective (gesture) non-verbal communicative abilities in an attempt to correlate non-verbal communicative abilities with site of lesion. Data analysis revealed that left-hemisphere damaged subjects exhibited greater deficits in symbolic non-verbal behaviour compared to those with right-hemisphere damage and normal controls. The right-hemisphere damaged subjects demonstrated greater affective non-verbal impairment than those with left-hemisphere damage and normals, but the differences between right-hemisphere damaged subjects and left-hemisphere damaged subjects on affective mean rank scores were small. Lesion location either anterior or posterior to the Rolandic fissure did not differentiate between receptive versus expressive non-verbal abilities.