Biomedical subjects

Lorie G Richards

Publications and source records attributed to Lorie G Richards.

6 recordsLinked to original sources

PubMed2006

Task switching after stroke.

BACKGROUND AND PURPOSE: Task switching is a cognitive skill that may be compromised after brain damage. The purposes of this study were to examine task-switching abilities in the subacute phase after stroke, to determine whether a switching task under endogenous or internal control is more difficult than a switching task under exogenous or cued control, and to determine whether deficits in switching attenuate in the first few months after stroke. SUBJECTS: The participants in this study were 46 adults with stroke and 38 adults without stroke. METHODS: Subjects performed 2 computer-based switching tasks, an alternating task that relied on endogenous control and a cued task that relied on exogenous control. Testing was done in subjects' homes at 1 and 3 months after stroke and at a 2-month interval for control subjects. Switch costs, or the difference between the no-switch condition and the switch condition, were calculated for accuracy and response time. RESULTS: Subjects in the stroke group had higher switch costs for accuracy than did subjects in the control group. The alternating task was more difficult than the cued task, with higher switch costs for accuracy and response time. The alternating task was particularly difficult for subjects in the stroke group, with high switch costs for accuracy. Both groups showed decreased response time switch costs at the second testing session. DISCUSSION AND CONCLUSION: Task switching, particularly if under endogenous control, is impaired in adults in the subacute phase after stroke. Clinicians should be aware of performance deficits that may relate to task switching.

Aged↗

PubMed2005

Characterizing occupational therapy practice in stroke rehabilitation.

UNLABELLED: Richards LG, Latham NK, Jette DU, Rosenberg L, Smout RJ, DeJong G. Characterizing occupational therapy practice in stroke rehabilitation. OBJECTIVES: To describe how occupational therapy (OT) activities during stroke inpatient rehabilitation vary by admission functional status and over time and how time spent in these various activities relates to functional status at discharge. DESIGN: Observational cohort study. SETTING: Six inpatient rehabilitation hospitals in the United States. PARTICIPANTS: People (N=713) receiving 4 to 19 hours of post-stroke OT. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Patients were categorized by number of 4-hour blocks of OT received and by admission upper-extremity (UE) dressing score on the FIM instrument. In each group, the percentage of time spent in 16 activities and the percentage of patients who received each activity were calculated. The amount of time in activities was compared for those patients scoring 1 or 2 at admission who achieved at least a level of supervision for UE dressing (a score of >or=5) using Wilcoxon 2-sample tests. RESULTS: The majority of OT time was spent in impairment-focused activities (37.5%) or training basic activities of daily living (31.9%). Treatment progressed to more advanced activities over time (eg, less bed mobility, more home management), yet little time was spent on community integration or leisure activities and with very few patients. Successful patients received more higher-level activities, whereas unsuccessful patients received larger amounts of basic-level activities. CONCLUSIONS: OT activities focused on a combination of remediating impairments and retraining specific functional tasks, at the ability level of each individual patient, and provided higher-level activities as patients improved their function. More time in higher-level activities was related to greater success in rehabilitation. However, higher-level activities remain the least common activities provided during inpatient rehabilitation.

Activities of Daily Living↗

PubMed2005

Physical therapy during stroke rehabilitation for people with different walking abilities.

UNLABELLED: Latham NK, Jette DU, Slavin M, Richards LG, Procino A, Smout RJ, Horn SD. Physical therapy during stroke rehabilitation for people with different walking abilities. OBJECTIVE: To describe how physical therapy (PT) activities during post-stroke inpatient rehabilitation vary by admission walking ability and over time. DESIGN: Observational cohort study. SETTING: Six inpatient rehabilitation hospitals in the United States. PARTICIPANTS: People receiving post-stroke PT (N=715) who were classified as walking at admission. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Percentage of time spent in 11 activities, percentage of patients who participated in each activity, and the FIM instrument scores. RESULTS: The majority of PT time was spent in gait activities. Even people with the most limited mobility spent 25% to 38% of PT time in gait activities during the first 6-hour treatment block. Treatment progression was evident, and a shift to more advanced activities occurred over time (eg, less bed mobility and more advanced gait). However, even in the final 6-hour block, a small proportion of time was spent on community mobility activities (1.2%-5.2%), and most people received no community mobility training. CONCLUSIONS: PT activities focused on specific functional tasks at the ability level of each individual patient and provided higher-level activities as patients improved their function. However, although there is increasing recognition that the environment influences task performance, little time was spent in community mobility activities before discharge.

Activities of Daily Living↗

PubMed2003

Attentional abilities and functional outcomes following stroke.

Although stroke affects cognitive functioning as well as motor functioning, research on cognitive consequences has lagged behind that focused on motor function. The evidence that is accruing suggests that cognitive function is importantly related to successful rehabilitation. The present study examined two aspects of attentional functioning (divided attention and switching attention) in older adult stroke survivors and healthy older adults. In addition, the authors investigated the relation between attention and functional outcomes following stroke. Results revealed stroke-related deficits in both of the types of attention as well as significant associations between attentional functioning and both physical and social outcome measures. Poorer attentional performance was associated with a more negative impact of stroke on daily functioning. These findings suggest an important role for attention in post-stroke function and provide information that can contribute to improving outcomes following stroke.

Aged↗

PubMed2002

The effects of age and feedback on isometric knee extensor force control abilities.

OBJECTIVE: To investigate the effects of age and feedback on submaximal isometric force control abilities in the knee extensors. DESIGN: Analysis of a force control task in a quasi-experimental design. BACKGROUND: The ability to control submaximal strength is important to accomplish activities of daily living. The purpose of this study was to investigate the effects of age, feedback, and force level on force control ability in knee extension, which is often used to accomplish daily activities. METHODS: The performance of an isometric force control task was measured in young (mean age 26, SD 2.7 yrs) and older (mean age 72, SD 2.0 yrs) adult healthy male participants. Each participant maintained a steady force in knee extension at two levels of force (20% and 60% MVC) with and without visual bandwidth feedback. Age, force level, and feedback effects were examined on the dependent variables of force variability, bias, and time in bandwidth. RESULTS: Both groups were fairly accurate at accomplishing the task, particularly at the lower force level. The higher force was harder to control, particularly when feedback was absent. The absence of feedback did not affect variability during force control. Older adults performed with less variability and a higher safety margin. Both groups performed better in time spent in bandwidth and safety margin with visual feedback, compared to the no-feedback condition. CONCLUSIONS: Healthy older and younger adults performed quite similarly regardless of feedback being provided or not. The intermittent feedback condition may have been more closely aligned with a no feedback condition rather than a continuous feedback condition. RELEVANCE: Clinical evaluation of submaximal force control ability may be useful for delineating impairments in motor skill and measuring outcomes of intervention programs. To be useful in the clinic, force control assessments must be both sensitive and specific to underlying impairments. The current study investigated the normal range of force control variability to allow the detection of true impairments.

Adult↗

PubMed2002

Effects of age, step direction, and reaction condition on the ability to step quickly.

BACKGROUND: The ability to take a step quickly is important for balance maintenance during activities of daily living. The purpose of this study was to investigate the effects of age, reaction condition, and step direction on the ability to take a volitional step as fast as possible. METHODS: The performance of a voluntary step task was measured in young adult (mean age 20, SD 0.9 years), young-old adult (mean age 67, SD 3.7 years), and old adult (mean age 78, SD 2.3 years) healthy female participants. Each participant stepped as fast as possible in eight directions in response to a visual cue in a simple or choice reaction time condition. The effects of age, reaction condition, and step direction and their interactions on the primary outcome variables of response time, step liftoff, and step landing time were examined. RESULTS: The normal aging process progressively increased the response, liftoff, and landing times. The choice reaction time condition, compared to the simple, had significantly increased response, liftoff, and landing times. Step direction significantly affected the liftoff and landing times, with lateral, diagonal, and anterior and posterioir (A-P) times increasing, respectively. CONCLUSIONS: We found substantial declines in the ability to step rapidly in healthy adults as age increased. When a decision was required regarding the step direction, the step performance also declined. Step direction also significantly affected step performance. The assessment of voluntary step performance, which may be an indicator of balance ability, should include dimensions of both direction and the choice condition.

Adult↗