Motor Imagery Deficits in High-Functioning Older Adults and its Impact on Fear of Falling and Falls

Overestimation associated with walking and balance function in individuals diagnosed with a stroke

BACKGROUND

An estimation error is the difference between motor imagery and actual motor time. Previous studies have reported that overestimation (motor imagery time < actual motor time) is related to physical functions in healthy individuals. However, this finding is unclear among individuals diagnosed with a stroke.

OBJECTIVE

We investigated whether overestimation is related to physical function in individuals diagnosed with a stroke.

METHODS

This study included 71 individuals diagnosed with a stroke (mean age, 67.2 ± 13.4 years; mean time since stroke, 68.4 ± 44.7 days). Imagined timed up and go test (iTUGT) was performed to assess the estimation error. First, the iTUGT was performed; subsequently, the TUGT was performed. The estimation error was calculated by subtracting the TUGT from the iTUGT, with two standard deviations (2 SDs) being calculated. Furthermore, patients were classified into appropriate estimation (AE, within ±2 SD) and overestimation (OE, over -2 SD) groups. Both groups were tested using the estimation error, iTUGT, TUGT, Berg Balance Scale (BBS), and Brunnstrom Recovery Stage (BRS). Subsequently, a correlation analysis was performed.

RESULTS

The OE group had a significantly higher estimation error than the AE group (OE: -7.08 ± 6.87 s, AE: -0.29 ± 1.53 s, P < .001). Moreover, the OE group had significantly lower TUGT and BBS than the AE group. The estimation error was correlated with the TUGT, BBS, and lower-limb BRS (ρ = -0.454, 0.431, 0.291, respectively; P < .05).

CONCLUSIONS

Overestimation was associated with TUGT and balance function in individuals diagnosed with a stroke.

The global prevalence of and risk factors for fear of falling among older adults: a systematic review and meta-analysis

BACKGROUND

As a common psychological problem among older adults, fear of falling was found to have a wide range prevalence in different studies. However, the global prevalence of it was unknown and a lack of the large sample confirmed its risk factors.

OBJECTIVES

To report the global prevalence of fear of falling and to explore its risk factors among older adults for further developing precise interventions to systematically manage FOF.

DESIGN

A systematic review and meta-analysis was conducted by PRISMA guidelines.

METHODS

Searches were conducted in PubMed, Web of Science, EMBASE, the Cochrane Library and the manual search in August 20, 2022, updated to September 2, 2023. Observational studies published in English were included and two researchers independently screened and extracted the data. Fixed or random effects mode was used to estimate the pooled prevalence of and risk factors for fear of falling. Heterogeneity resources were analyzed by subgroup and sensitivity analysis. Publication bias was assessed through funnel plots, Egger's test and Begg's test.

RESULTS

A total of the 153 studies with 200,033 participants from 38 countries worldwide were identified. The global prevalence of fear of falling was 49.60%, ranging from 6.96-90.34%. Subgroup analysis found the estimates pooled prevalence of it was higher in developing countries (53.40%) than in developed countries (46.7%), and higher in patients (52.20%) than in community residents (48.40%). In addition, twenty-eight risk factors were found a significant associations with fear of falling, mainly including demographic characteristics, physical function, chronic diseases and mental problems.

CONCLUSION

The global prevalence of FOF was high, especially in developing countries and in patients. Demographic characteristics, Physical function, chronic diseases and mental problems were a significant association with FOF. Policy-makers, health care providers and government officials should comprehensively evaluate these risk factors and formulate precise intervention measures to reduce FOF.

TRIAL REGISTRATION

The study was registered in the International Database of Prospectively Registered Systematic Reviews (PROSPERO): CRD42022358031.

Longitudinal Changes in Motor Estimation Error and Motor Function in Patients with Parkinson's Disease: A Case Report

BACKGROUND AND OBJECTIVES

This report described two cases with clear longitudinal changes in motor estimation error (difference between the motor imagery and motor execution) and their progression and motor and activities of daily living (ADL) function changes in patients with PD.

MATERIALS AND METHODS

Patient 1 was a 68-year-old man (Hoehn and Yahr [H and Y] stage: IV, diagnosed with PD for 11.8 years) and patient 2 was a 68-year-old woman (H and Y stage: II, diagnosed with PD for 9.6 years). Imagined two-step test (iTST), two-step test (TST), and PD-related assessments (Unified Parkinson's Disease Rating Scale [UPDRS], and Freezing of Gait Questionnaire [FOGQ]) were assessed at baseline and after 6 months. Motor estimation error was calculated as the iTST distance minus TST distance.

RESULTS

In patient 1, motor estimation error was greater after 6 months (baseline: 5.7 [4.8%]/after 6 months: 25.7 cm [26.1%]). Moreover, UPDRS and FOGQ total scores deteriorated after 6 months (UPDRS total: 29/34 point, and FOGQ: 9/16 point). Conversely, in patient 2, motor estimation error did not change notably (-3.6 [7.6%]/-2.5 cm [7.0%]), while UPDRS and FOGQ total scores improved after 6 months (UPDRS total: 17/12 point, and FOGQ: 6/1 point).

CONCLUSIONS

This report indicated that greater motor estimation error may be associated with declining motor and ADL function and disease progression in patients with PD.

Estimation Error Consisting of Motor Imagery and Motor Execution in Patients with Stroke

Previous studies demonstrate that the difference between motor imagery and actual tasks (estimation error) is related to cognitive and physical functions and that a large estimation error (LE) is related to motor imagery ability, including cognitive and physical functions in healthy subjects. The purpose of this study investigated whether estimation error is related to physical and cognitive function in patients with stroke. The study included 60 patients with stroke. The Timed Up and Go Test (TUGT) was employed to assess estimation error. First, the imagined TUGT (iTUGT) was performed; thereafter, the actual TUGT was performed. The estimation error was calculated by subtracting TUGT from iTUGT, with conversion to the absolute value. The patients were classified into the small estimation error (SE) and LE groups, with comparisons of various clinical scores (Mini-Mental State Examination, Berg Balance Scale, 10-m walking speed, Brunnstrom Recovery Stage, and Functional Independence Measure). As a result, the estimation error was significantly larger in the LE group than in the SE group. Cognitive function and balance ability were significantly lower in the LE group than in the SE group. In conclusion, the estimation error was related to physical and cognitive functions in patients with stroke.

Relationship between the vividness of motor imagery and physical function in patients with subacute hemiplegic stroke: a cross-sectional preliminary study

PURPOSE

The study aimed to clarify whether the vividness of motor imagery is related to lower limb function and walking ability in patients with hemiplegic stroke.

MATERIALS AND METHODS

The study was a cross-sectional preliminary study. The subjects were 15 patients with hemiplegic stroke. The vividness of motor imagery was assessed using the kinesthetic and visual imagery questionnaire. The kinesthetic imagery (KI) involves the sensation of one's own movement, whereas the visual imagery (VI) involves the imagination of a third-person performing the self-movement. Their physical functions were assessed using the Brunnstrom recovery stage, stroke impairment assessment set, 10-m maximum walking speed test, and functional independence measure. KI and VI were compared using the t test. Correlation analysis was performed between KI or VI and various variables as well as between the motor imagery gap (difference between KI and VI) and various variables.

RESULTS

KI was significantly lower than VI (p < .01). KI was correlated not only with lower limb function (r = 0.68) but also with walking speed (r = -0.64). The motor imagery gap was correlated with hip joint function (r = -0.53).

CONCLUSIONS

KI and motor imagery gap were associated with lower limb function and walking ability.