Karen P. Y. Liu

Prof. Karen P. Y. Liu

orcid

Research Focus & Metrics

Academic Career Length

28Years (1999-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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24 April 2018 in Neural Plasticity
Verified
Journal Article
Open access
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JZJack Jiaqi ZHANG
Jack Jiaqi ZHANG
KFKenneth N. K. Fong
Kenneth N. K. Fong
NWNandana Welage
Nandana Welage
KLKaren P. Y. Liu
Karen P. Y. Liu
Objective. To evaluate the concurrent and training effects of action observation (AO) and action execution with mirror visual feedback (MVF) on the activation of the mirror neuron system (MNS) and its relationship with the activation of the motor cortex in stroke individuals. Methods. A literature search using CINAHL, PubMed, PsycINFO, Medline, Web of Science, and SCOPUS to find relevant studies was performed. Results. A total of 19 articles were included. Two functional magnetic resonance imaging (fMRI) studies reported that MVF could activate the ipsilesional primary motor cortex as well as the MNS in stroke individuals, whereas two other fMRI studies found that the MNS was not activated by MVF in stroke individuals. Two clinical trials reported that long-term action execution with MVF induced a shift of activation toward the ipsilesional hemisphere. Five fMRI studies showed that AO activated the MNS, of which, three found the activation of movement-related areas. Five electroencephalography (EEG) studies demonstrated that AO or MVF enhanced mu suppression over the sensorimotor cortex. Conclusions. MVF may contribute to stroke recovery by revising the interhemispheric imbalance caused by stroke due to the activation of the MNS. AO may also promote motor relearning in stroke individuals by activating the MNS and motor cortex.

2 July 2020 in BMC Geriatrics
Verified
Journal Article
Open access
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MIMonisha Ingold
Monisha Ingold
NTNikki Tulliani
Nikki Tulliani
CCChetwyn C. H. Chan
Chetwyn C. H. Chan
KLKaren P. Y. Liu
Karen P. Y. Liu
Background: Physical activity can be classified as open-skilled or closed-skilled. Open-skilled physical activity, such as tennis, require participants to perform within a dynamic setting and respond to unpredictable and frequent environmental changes throughout the activity. Closed-skilled types of physical activity, such as swimming, are predictable and self-directed. However, the benefits of cognitive function in these two types of physical activities to older adults are unknown. This study examined the effects of participation in open- and closed-skilled physical activity on the cognitive function of older adults. Methods: The study recruited a total of 61 participants aged 65 years and over. Participant recruitment was achieved by distributing flyers asking for volunteers in various sports venues. Participants self-reported to be without medical conditions affecting their physical and cognitive function. All participants underwent a two-hour assessment session involving the completion of seven standardised cognitive function assessments, which were used to assess a range of cognitive function. Results: Overall mean scores across all of the assessments showed superior performance for the open- or closed-skilled participants when compared with the no-physical-activity group. The results of 61 adults who participated in this study showed that closed-skilled physical activity was associated with better selective attention and visuospatial function while open-skilled physical activity was associated with better inhibition and cognitive flexibility function. No significant difference in self-regulation ability was found between the open- or closed-skilled groups. Conclusions: Open-skilled physical activity was associated with better inhibition, visual tracking, and cognitive flexibility while closed-skilled physical activity was associated with better selective attention and visuospatial perception. The findings have important practical implications for the health and quality of life of ageing populations, knowing which particular types of physical activity might affect the cognitive function.

20 October 2013 in Australian Occupational Therapy Journal
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Journal Article
Closed access
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AKAdeline Y. Kho
Adeline Y. Kho
KLKaren P. Y. Liu
Karen P. Y. Liu
RCRaymond C. K. Chung
Raymond C. K. Chung

1 January 2019 in Medicine
Verified
Journal Article
Open access
TWTowel K.K. Wong
Towel K.K. Wong
AMAda W.W. Ma
Ada W.W. Ma
KLKaren P. Y. Liu
Karen P. Y. Liu
Louisa Ming Yan ChungLouisa Ming Yan Chung
Louisa Ming Yan Chung
YBYoung-Hyeon Bae
Young-Hyeon Bae
HWHsing-Kuo Wang
Hsing-Kuo Wang
In this study, balance performance, agility, eye–hand coordination, and sports performance were compared between amateur badminton players and active controls. Thirty young adult badminton players and 33 active controls participated in the study. Static single-leg standing balance (with eyes closed) was measured using a force platform, and dynamic balance was measured using the Y Balance Test (lower quarter). Agility was measured using a hexagon agility test, and eye–hand coordination was measured using a computerized finger-pointing task. Sports performance was quantified by the number of times a shuttlecock fell in a designated area following a badminton serve. The badminton players had superior accuracy in badminton serving (P < .001) relative to the active controls. However, no significant between-group differences were noted in all other outcome variables (P > .05). Amateur badminton players had more favorable sports performance, but not balance performance, agility, or eye–hand coordination, than controls.

1 January 1999 in The Journals of Gerontology, Series A: Biological Sciences and Medical Sciences
Verified
Journal Article
Open access
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LCLeung-Wing Chu
Leung-Wing Chu
CPConrad Kw Pei
Conrad Kw Pei
ACAlice Chiu
Alice Chiu
KLKaren P. Y. Liu
Karen P. Y. Liu
MCMary Ml Chu
Mary Ml Chu
AWAlan Wong
Alan Wong
Background. The incidence of falls among older hospitalized patients is higher than that of community-dwelling older persons. Prevention is important, but factors associated with these falls are less well studied than falls occurring in the community or nursing homes. Methods. This study was conducted in an acute-care general hospital in Hong Kong. During November 1995 to March 1997, all older inpatients who fell during hospitalization were assessed by a geriatrician, a physiotherapist, and an occupational therapist. A standardized protocol to study the clinical and performance-oriented functional factors was employed. A sex- and age-matched hospital control was recruited for each case. In total, 51 cases and controls (mean ages 77.8 ± 7.3 years and 77.5 ± 7.0 years, respectively) were studied. Results. Among the multiple clinical and functional risk factors for falls identified, lower limb weakness (i.e., power less than MRC grade 4 in one or both lower limbs) and poor tandem walk ability emerged as two significant predictive factors for falls in the hospital. The overall classification accuracy of fallers and nonfallers was 79%. The sensitivity was 84% and specificity was 75%. Clinical factors were the underlying causes for the lower limb weakness and poor tandem walk performance. Conclusions. Among clinical and functional risk factors for falls in the older medical patient, lower limb weakness and poor tandem walk ability were most predictive. Falls prevention programs in hospitals should employ these two tests as screening instruments.