Dual-task Conditions Research Articles

A-02 Concussion at One-Year Post-Injury and Anxiety Do Not Predict Head Protective and Jump Landing Functional Reaction Time

Abstract Purpose: Individuals with a concussion history are more likely to sustain subsequent concussions and/or musculoskeletal injuries. Underlying mechanisms are unclear; reaction time (RT) deficits associated with anxiety may play an important role. The primary aim of this study was to determine if anxiety and recent concussion history predict functional RT (i.e., head protective, jump landing) under single and dual-task conditions. Methods: 40 participants (concussion:healthy = 20:20; time since concussion = 11.8 months) completed the State–Trait Anxiety Inventory, anxiety ratings before and after each task, and performed RT tasks. We used a virtual reality environment and motion capture laboratory to collect RTs for head protective and jump landing, respectively. Participants completed assessments under both single-task (i.e., “Focus solely on completing the task as quickly as possible”) and dual-task (i.e., “Subtract as quickly and accurately as possible as you await your visual stimulus”) conditions. Instructions gave equal weight to speed and accuracy. All RTs were calculated (ms) as the time from visual onset of stimuli to first movement ≥3 cm of hands (head protective) or sacral body (jump landing). A series of linear regression models determined if the independent variables predicted RTs. Results: Regression models did not explain a significant proportion of the variance in head protective (single- R2 = 0.05; p = 0.78; dual- R2 = 0.09; p = 0.49), or jump landing (single- R2 = 0.21; p = 0.08; dual- R2 = 0.12; p = 0.32) RTs. Conclusions: In a low anxiety sample, recent concussion history and anxiety do not predict clinical or functional reaction times at twelve-months post-concussion. If these differences exist, they are likely resolved by this time.

Attentional Demand of a Movement Sequence Guided by Visual-Spatial and by Motor Representations

The objective of the experiment was to assess the change in attentional demands of a movement sequence guided by visual-spatial and motor representations across practice sessions in a dual-task probe paradigm. Participants were randomly assigned to either a 1-day or 2-day practice group. Following acquisition of the motor sequence task, participants first conducted a retention test and then four inter-manual transfer tests under single and dual-task conditions. The probe task was a simple reaction time. The inter-manual transfer tests, consisting of a mirror and non-mirror test, examined the development of the motor and visual-spatial representation, respectively. The results indicated that both representations guided the movement sequence and required attention. The attentional demands did not change with additional practice.

Smart Wearable Device for Quantification of Risk of Fall: Exploring Role of Gait Phases and Knee Bending Angle for Parkinson's Patients.

Gait disturbances with falls are common among patients with Parkinson's disease. Falls commonly occur from slips while walking on pathways with turns. Gait phases namely Loading Response and Terminal Stance are linked with forward and backward slips. Also, postural deformities (connected with knee joint angles) are debilitating symptoms of Parkinson's patients and are related with falls. Here, we have focused on exploring the contribution of Loading Response and Terminal Stance to risk of fall along with the relevance of postural deformity (e.g., knee bending) while an individual walked overground on pathways (with 0° and 180° turn) under dual task condition. For this, we have used a wearable device consisting of a pair of Sensored shoes and Knee Bending Angle Recorder Units. The device was used to compute Coefficient of Variation of knee bending angle during different gait phases as an indicator of one's risk of fall that corroborated with clinical measure. Clinical Relevance- A study with age and gender matched healthy and Parkinson's individuals indicated the importance of Loading Response and pathway turn while assessing risk of fall. This can serve as important pre-clinical input while designing intervention paradigms.

Portable Electromyogram-sensitive System for Assessment of Fear of Fall: Relevance of Gait Phases for Post-Stroke Patients.

Post-stroke patients often suffer from gait deficits along with Fear of Fall (FoF) that adversely affect their ambulation. The FoF has been reported to be negatively correlated with one's performance in daily life. Clinical scales, e.g., Falls Efficacy Scale are often used to assess one's FoF. Though powerful, it can suffer from subjectivity. Thus, it is important to have reliable assessment of FoF. Motivated by this, we used one's lower limb muscle activation during specific gait phases to assess one's FoF. For this, we developed a portable electromyogram-sensitive system that can synchronously measure one's muscle activation along with gait phases. We conducted an experimental study with post-stroke patients and age-matched healthy controls who walked under Dual-Task condition. We investigated the lower limb muscle (Gastrocnemius Lateralis (GM) and Tibialis Anterior (TA)) activation during Loading Response, Terminal Stance and Initial Swing phases of gait, associated with slips contributing to FoF. Results show that our system could quantify the disparity (∆) in muscle activation between the affected and unaffected sides of patients (∆ = ∼84% during Loading response for both GM and TA, ~32%for GM during Terminal Stance and TA during Initial Swing) which was considerably higher than that between dominant and non-dominant sides of healthy controls. This might infer reduced dynamic stability of patients leading to their FoF. Also, muscle activation could classify patients from healthy controls with 90% accuracy during Loading Response and Initial Swing phases with clinical relevance in diagnostics and monitoring rehabilitation outcomes. Clinical Relevance- This study indicated that our system has potential to be utilized as a tool for diagnostic and monitoring rehabilitation outcomes as it can quantify the residual muscle ability of the post-stroke patients during gait.

Prefrontal Cortex Brain Activation During Texting and Walking: A Functional Near-Infrared Spectroscopy Feasibility Study

Texting while walking is an increasingly common, potentially dangerous task but its functional brain correlates have yet to be reported. Therefore, we evaluated prefrontal cortex (PFC) activation patterns during single- and dual-task texting and walking in healthy adults. Thirteen participants (29-49years) walked under single- and dual-task conditions involving mobile phone texting or a serial-7s subtraction task, while measuring PFC activation (functional near-infrared spectroscopy) and behavioral task performance (inertial sensors, mobile application). Head lowering during texting increased PFC activation. Texting further increased PFC activation, and decreased gait performance similarly to serial-7 subtraction. Our results support the key role of executive control in texting while walking.

Could direct and generative retrieval be two flips of the same coin? A dual-task paradigm study.

Autobiographical memories are thought to be retrieved using two possible ways: a generative one, which is effortful and follows a general-to-specific pathway, and a direct one, which is automatic and relatively effortless. These two retrieve processes are known to differ on the quantitative side (especially considering retrieval times), from a qualitative point of view; however, evidence is missing. Here, we aimed to disentangle this question by taking advantage of a dual-task paradigm in which the different tasks tax different executive functions. Participants were asked to perform an autobiographical memory task under three different conditions: no cognitive load, non-visual cognitive load and visual cognitive load. On the quantitative side, results replicated previous findings with generative processes being slower compared with direct ones. Conversely, on the qualitative side, results indicated that the retrieval times of both direct and generative retrieval processes varied similarly according to the dual-task condition, thus supporting the idea that the same memory process could underlie both retrievals.

Network-Based Transcranial Direct Current Stimulation May Modulate Gait Variability in Young Healthy Adults.

PurposePrevious studies have linked gait variability to resting-state functional connectivity between the dorsal attention network (DAN) and the default network (DN) in the brain. The purpose of this study was to examine the effects of a novel transcranial direct current stimulation (tDCS) paradigm designed to simultaneously facilitate the excitability of the DAN and suppress the excitability of the DN (i.e., DAN+/DN-tDCS) on gait variability and other gait characteristics in young healthy adults.MethodsIn this double-blinded randomized and sham-controlled study, 48 healthy adults aged 22 ± 2 years received one 20-min session of DAN+/DN-tDCS (n = 24) or no stimulation (the Sham group, n = 24). Immediately before and after stimulation, participants completed a gait assessment under three conditions: walking at self-selected speed (i.e., normal walking), walking as fast as possible (i.e., fast walking), and walking while counting backward (i.e., dual-task walking). Primary outcomes included gait stride time variability and gait stride length variability in normal walking conditions. Secondary outcomes include gait stride time and length variability in fast and dual-task conditions, and other gait metrics derived from the three walking conditions.ResultsCompared to the Sham group, DAN+/DN-tDCS reduced stride length variability in normal and fast walking conditions, double-limb support time variability in fast and dual-task walking conditions, and step width variability in fast walking conditions. In contrast, DAN+/DN-tDCS did not alter average gait speed or the average value of any other gait metrics as compared to the sham group.ConclusionIn healthy young adults, a single exposure to tDCS designed to simultaneously modulate DAN and DN excitability reduced gait variability, yet did not alter gait speed or other average gait metrics, when tested just after stimulation. These results suggest that gait variability may be uniquely regulated by these spatially-distinct yet functionally-connected cortical networks. These results warrant additional research on the short- and longer-term effects of this type of network-based tDCS on the cortical control of walking in younger and older populations.

Dual-Task Effects on Concurrent Speech Production in School-Age Children With and Without Stuttering Disorders.

Contemporary motor theories indicate that well-practiced movements are best performed automatically, without conscious attention or monitoring. We applied this perspective to speech production in school-age children and examined how dual-task conditions that engaged sustained attention affected speech fluency, speech rate, and language productivity in children with and without stuttering disorders. Participants included 47 children (19 children who stutter, 28 children who do not stutter) from 7 to 12 years of age. Children produced speech in two baseline conditions with no concurrent task and under a dual-task condition requiring sustained attention to on-screen stimuli. Measures of speech fluency, speech rate, and language productivity were obtained for each trial and compared across conditions and groups. Dual-task conditions resulted in a reduction in stutter-like disfluencies relative to the initial baseline speaking condition. Effects were similar for both groups of children and could not be attributed to decreases in language productivity or a simple order effect. Findings suggest that diverting attention during the process of speech production enhances speech fluency in children, possibly by increasing the automaticity of motor speech sequences. Further research is needed to clarify neurophysiological mechanisms underlying these changes and to evaluate potential clinical applications of such effects. https://doi.org/10.23641/asha.19945838.

Influence of Different Dual-Task Conditions During Straight or Curved Walking on Gait Performance of Physically Active Older Women With Cognitive Decline.

Real-world walking requires shifting attention from different cognitive demands to adapt gait. This study aims to evaluate the effect of dual tasking on spatiotemporal gait parameters of older adults. Participants were asked to perform a primary complex single-walking task, consisting of a fast-paced linear and a curved gait. Primary task was performed separately and simultaneously with different motor and cognitive secondary tasks. Spatiotemporal gait parameters, walk ratio, and walk stability ratio were measured. Apart from stride length, which stood relatively unchanged, gait speed and cadence were strongly affected by cognitive dual tasking. Cadence seems to be the most impacted by dual tasking during curved gait as it combines challenges of both primary and secondary tasks. Also, during curved phase, walking ratio was significantly lower and stability ratio was greater demonstrating that participants adopted a cautious gait where maintenance of stability took preference over efficiency.

The impact of divided attention on automatic postural responses: A systematic review and meta-analysis.

Quick responses to a loss of balance or "automatic postural responses" (APRs) are critical for fall prevention. The addition of a distracting task- dual-tasking (DT), typically worsens performance on mobility tasks. However, the effect of DT on APRs is unclear. We conducted a systematic review and meta-analyses to examine the effects of DT on spatial, temporal, and neuromuscular components of APRs and the effect of DT on cognitive performance. A Meta-analysis of 19 cohorts (n=329) showed significant worsening in spatial kinematic features of APRs under DT conditions (P=0.01), and a meta-analysis of 9 cohorts (n=123) demonstrated later muscle onset during DT (P=0.003). No significant DT effect was observed for temporal kinematic outcomes in 18 cohorts (n=328; P=0.47). Finally, significant declines in cognitive performance were evident in 20 cohorts (n=400; P=0.002). These results indicate that, despite the somewhat reactive nature of APRs, the addition of a secondary task negatively impacts some aspects of the response. These findings underscore the importance of cortical structures in APR generation. Given the importance of APRs for falls, identifying aspects of APRs that are altered under DT may inform fall-prevention treatment approaches.

Does secondary cognitive task affect knee force production sense in young male soccer players?

Objective: The aim of the present study is to compare the knee force production sense error (KFPSE) of young soccer players under single and dual-task conditions. Materials and Methods: Twenty-four young male soccer players with a soccer license participated in this study. Knee force production sense (KFPS) was evaluated using a biofeedback device. In order to compare the KFPSE first, the bilateral KFPS of the participants was evaluated. Then the same assessment was performed concurrently with a cognitive dual task (five countdowns from 200). Results: The results revealed that, compared with the single-task condition, players had higher absolute error under the dual-task condition for both extremities (p˂0.05). Conclusion: Secondary cognitive task may be a possible critical factor reducing the accuracy of the force (re)production sense. A secondary cognitive task may adversely affect the KFPS.

The effect of reducing attentional resources on selective suppression in the Simon task.

Studies using reaction times (RTs) distribution methods find that the Simon effect is greater for fast RTs and becomes smaller or reversed for slow RTs. However, the exact mechanisms responsible for this reduction are under debate. This study addressed the issue of whether attentional resources play a role in reduction of the Simon effect over time by investigating whether it is influenced by attentional constraints in a dual-task paradigm. Participants were instructed to perform a Simon task concurrently with a secondary task. Secondary task characteristics were manipulated by varying the overlap between the secondary task and the Simon task. Specifically, secondary tasks varied in their stimulus modality (auditory or visual) and/or response type (verbal or manual and lateralised or not). Distribution analyses of RTs, in the form of delta-plot functions, were performed for both the single- and dual-task conditions. Results showed that the more attention the secondary task demanded, the less the Simon effect was reduced, even for slower RTs. This suggests that the mechanisms responsible for the reduction of Simon effect over time are under top-down control.

Cognitive-Motor Interference during Dual Tasks in Blind Children

The aim of the present study was to compare the dual-task (DT) performance in blind children with sighted ones while concurrently performing a motor task (upright standing) with cognitive (Letter fluency (LF) or Category fluency (CF)) tasks. The Center of pressure mean velocity (CoPVm) and the cognitive performances were recorded during single (ST) and DT conditions. Results showed that, for both groups, CoPVm values increased significantly (p < 0.05) in the DT compared to ST condition. The CoPVm values were significantly (p < 0.001) higher in blind children, compared to controls only in the DT-CF condition. In conclusion, balance performance of blind and typically developed children is affected by dual tasking. Interference between motor and cognitive tasks has more pronounced effects on balance performance in blind children, compared to controls. This difference was observed only when performing the CF task concurrently with the postural balance task.

Effect of individualized cognitive and postural task difficulty levels on postural control during dual task condition

BackgroundPrevious dual task studies suggested that the difficulty of the concurrent cognitive and motor tasks may not be challenging to the same degree for each person. This study approaches this problem by setting individualized difficulty levels for tasks to examine the dual task interference. Research questionDo the features of postural sway depend on increased individualized difficulty levels of concurrent cognitive and postural activities? Methods20 young healthy participants (10 male, 10 female) took part in the study. Before the experiments, cognitive task difficulty (No-, Medium-, High) has been set individually. Subjects performed postural tasks (quiet stance, voluntary sway) concurrently with or without a cognitive task which based on simple arithmetic calculations. Postural sway features were examined. ResultsPostural sway features were affected by individualized difficulty level of concurrent cognitive and postural activities. In voluntary sway, as a more challenging postural task, higher reductions were observed for such sway features as COP velocity and range in AP direction. SignificanceThis study signaled task-specific changes in postural sway features. When the difficulty levels were set individually, the effect of motor and cognitive dual task was more apparent when the balance requirement of the primary motor task increased.

Dual-Task Abilities During Activities Representative of Daily Life in Community-Dwelling Stroke Survivors: A Pilot Study.

BackgroundIn addition to several physical skills, being able to walk in the community, walking independently and safely in the community requires the ability to divide attention between walking and other tasks performed simultaneously. The aims of the present pilot study were to measure cognitive-locomotor dual-task (DT) abilities during activities representative of daily living in stroke survivors and to compare them with age- and gender-matched healthy individuals.MethodsTo assess DT abilities, all participants walked along a virtual shopping mall corridor and memorized a 5-item shopping list. Two levels of task complexity were used for the walking task (with or without virtual agents to avoid) and the cognitive task to recall a list of items (with or without a modification at mid-course). The assessment was conducted using an omnidirectional platform and a virtual reality (VR) headset. Locomotor and cognitive DT costs (DTC) were calculated as the percent change from single-task (ST) performance. Walking speed and minimal distance between the participant and the virtual agents were used to characterize locomotor performance. Cognitive performance was assessed by the number of correctly recalled items. One-sample Wilcoxon tests were used to determine the presence of DTCs and Mann-Whitney tests were performed to compare DTCs between the 2 groups.ResultsTwelve community-dwelling stroke survivors [60.50 years old (25-75th percentiles: 53.50–65.75); 5 women; 13.41 months post-stroke (5.34–48.90)] and 12 age- and gender- matched healthy individuals were recruited. Significant cognitive or mutual (cognitive and locomotor) interferences were observed in participants with stroke in all DT conditions, except the simplest (no virtual agents, no modifications to the list). For the control group, significant mutual interferences were only observed during the most complex DT condition. A group difference was detected in cognitive DTCs during the most complex DT condition (virtual agents and list modifications; p = 0.02). Stroke survivors had greater cognitive DTCs than the control group.ConclusionsUsing an ecological perspective contributes to understanding behavior of stroke survivors in daily activities. Virtual scenarios appear to be an interesting avenue for a more comprehensive understanding of DT abilities during activities representative of daily living in stroke survivors. The usability and feasibility of such an approach will have to be studied before considering implementation in rehabilitation settings.

Smartphone Measured Single- and Dual-Task Gait Evaluation in Adolescents Post-Concussion: A Longitudinal Comparison to Healthy Controls

Background: Impairments in postural stability are common following concussion. However, subjectively-scored assessments of postural control, such as the Balance Error Scoring System, may not accurately reflect postural instability. Objective measures, such as gait performance, can more accurately identify ongoing impairments in postural control throughout concussion recovery. Recent technological advances make gait evaluations more feasible across different clinical settings. Purpose: To compare performance on smartphone measured single- and dual-task gait evaluations among adolescent concussion participants and healthy controls across two timepoints. Methods: We evaluated concussed participants at initial (n=13; 14.6±1.3 years; 54% female; 5.5±1.6 days post-concussion) and follow-up visits (33.2±3.3 days post-concussion), and healthy control participants (n=21; 15.5±1.6 years; 48% female) at two timepoints 27.3±0.7 days apart on single- and dual-task gait performance. Single-task gait trials consisted of walking at a self-selected pace for 20 meters. Single-task cognitive trials involved responding to a cognitive task while standing in place. For dual-task trials, participants completed gait and cognitive tasks simultaneously. During each trial a smartphone affixed to the lumbar spine measured gait velocity and cognitive response accuracy and response time. We conducted a 2x2 mixed effects ANOVA to examine changes between groups across the testing timeline. Results: Concussion participants reported significantly greater symptom severity than control participants at the initial timepoint (23.1±13.5 vs 7.4±8.5; p=0.001); however, this difference did not persist to the second timepoint (p=0.99). The concussion group demonstrated significant improvements in single-task gait velocity between timepoints; although, between-group differences in gait velocity were not observed at either timepoint (Figure 1). No differences in cognitive accuracy between groups were identified. However, concussed participants performed worse than healthy controls on cognitive response time at both time points in single- and dual-task testing (Figure 2). Further, response time improved between testing periods for single-task, but not dual-task, conditions. Conclusion: Smartphone gait evaluations indicate improvement in single-task gait velocity during concussion recovery. However, no significant differences in gait velocity were found between concussed and control participants at either time point in single- or dual-task gait conditions. Interestingly, concussion patients had slower cognitive responses than healthy controls at both time points, despite no differences in cognitive accuracy or symptom severity at time 2. Our preliminary findings suggest that smartphone gait evaluations are effective in measuring changes in gait velocity and cognitive performance following adolescent concussion, as well as detecting subtle differences in gait and cognitive performance between concussed and control patients throughout recovery. [Figure: see text][Figure: see text]

Robot-assisted gait training with auditory and visual cues in Parkinson's disease: A randomized controlled trial

Robot-assisted gait training (RAGT) may have beneficial effects on Parkinson's disease (PD); however, the evidence to date is inconsistent. This study compared the effects of RAGT and treadmill training (TT) on gait speed, dual-task gait performance, and changes in resting-state brain functional connectivity in individuals with PD. In this prospective, single-center, randomized controlled trial with a parallel two-group design, 44 participants were randomly allocated to undergo 12 sessions (3 times per week for 4 weeks) of RAGT or TT. The primary outcome was gait speed on the 10-m walk test (10mWT) under comfortable walking conditions. Secondary outcomes included dual-task interference on gait speed, balance, disability scores, fear of falling, freezing of gait, and brain functional connectivity changes. All clinical outcomes were measured before (T0), immediately after (T1), and 1 month after treatment (T2). The mean (SD) age of the participants was 68.1 (8.1) years, and mean disease duration 108.0 (61.5) months. The groups did not significantly differ on the 10mWT (T0-T1, p=0.726, Cohen's d=0.133; T0-T2, p=0.778, Cohen's d=0.121). We observed a significant time-by-group interaction (F=3.236, p=0.045) for cognitive dual-task interference, controlling for confounders. After treatment, coupling was decreased to a greater extent with RAGT than TT between the visual and dorsal attention networks (p=0.015), between bilateral fronto-parietal networks (p=0.043), and between auditory and medial temporal networks (p=0.018). Improvement in cognitive dual-task interference was positively correlated with enhanced visual and medial temporal network coupling overall (r=0.386, p=0.029) and with TT (r=0.545, p=0.024) but not RAGT (r=0.151, p=0.590). RAGT was not superior to intensity-matched TT on improving gait functions in individuals with PD but may be beneficial in improving gait ability under cognitive dual-task conditions. The therapeutic mechanism and key functional connectivity changes associated with improvement may differ between treatment strategies. GOV: #NCT03490578.

The Implication of Pathway Turn and Task Condition on Gait Quantified Using SmartWalk: Changes With Age and Parkinson's Disease With Relevance to Postural Strategy and Risk of Fall.

One’s gait can be affected by aging, pathway with turns, task demands, etc., causing changes in gait-related indices and knee flexion (influencing posture). Walking on pathways with turns threatens stability, affecting one’s gait-related indices and posture. The ability to overcome such deficits is compromised with age and neurological disorders, e.g., Parkinson’s Disease (PD) leading to falls. Also, task demands imposed by single and dual-task (e.g., counting backward while walking) conditions affect the gait of individuals using different postural strategies varying with age and neurological disorder. Existing research has investigated either the effect of the pathway with turn or task condition on one’s gait. However, none (to our knowledge) have explored the differentiated implications of the pathway with turn and task conditions on one’s gait-related indices and knee flexion while walking. Our study had two phases with 30 participants. Phase 1 had healthy adults (young and old) and Phase 2 had age and gender-matched healthy elderly and individuals with Parkinson’s disease (PD) who walked on pathways having turns under single and dual-task conditions. We analysed gait in terms of (i) gait-related indices (Phases 1 and 2) and (ii) knee flexion (Phase 2). Also, we analysed one’s counting performance during dual task. One’s gait-related indices and knee flexion were measured using a portable gait quantifier. The aim was to (i)understand whether both pathways with turn and task conditions are equally effective in affecting the gait of (a)individuals of varying ages and (b) gender-matched healthy older adults and individuals with PD, (ii)study variations of knee joint angles while walking on pathways having turns (under different task conditions) in terms of its clinical relevance, and (iii) explore the implication of pathway with turn on counting performance (with relevance to postural strategy) with varying age and PD. Results indicated that for the younger group, the task condition caused statistical variations in gait-related indices. For the older group, both pathways with turn and task conditions had statistical implications on gait-related indices. Additionally, individuals with PD demonstrated a higher variation in knee flexion than their healthy counterparts. Again, pathways with varying turns elicited variations in counting performance indicating different postural strategies being employed by the three groups.

Yaşlı bireylerde tek-görev, çift-görev ve ardışık fiziksel-bilişsel eğitimin düşme riski ve denge performansı üzerine etkileri: randomize çalışma

Purpose: This study aimed to examine the effects of single-task, dual-task and successive physical-cognitive training on fall risk, balance, and gait performances in elderly.Methods: A total of 45 healthy older adults (73.0±4.6 years; 6 male and 39 female) underwent one of three interventions 3 times a week for 4 weeks. Group-1 performed single-task balance and gait exercises. Group-2 performed cognitive activity, balance, and gait exercises simultaneously. Group-3 performed successive cognitive activities and balance and gait exercises. Gait speed under single-task and dual-task conditions, Berg Balance Scale, Timed up and Go test, and Tinetti's Falls Efficacy Scale scores were evaluated before and after 4 weeks of interventions.Results: Gait speed under single-task condition, Timed up and Go Test, and Berg Balance Scale scores were improved in all groups (p&amp;lt;0.05). Gait speed under dual-task condition was improved in Groups-2 and 3 (p&amp;lt;0.05). Group-3 had greater improvement in Berg Balance Scale and Timed up and Go test scores than Group-2. Tinetti's Falls Efficacy Scale was improved in Group-1 and 3 after training while the improvement was greater in Group-3 (p=0.001).Conclusion: The present study suggests that an intervention involving cognitive and physical activities results in greater improvement in gait speed than interventions involving physical activities alone. However, successive physical-cognitive training may be more effective in reducing fear of fall and improving balance skills in elderly.

The effects of proficiency level and dual-task condition on L2 self-monitoring behavior

AbstractThe current study examined the effects of task condition (TC; single vs. dual) and proficiency level (PL) on self-monitoring of second language (L2) speakers. Data were collected from sixty-six female L2 learners of English performing two speaking tasks under two task conditions. While performance in the single-task condition involved only narrating a picture-based oral narrative, the dual-task condition involved performing the same oral narrative as well as a secondary task. Factor analysis, MANOVA, and two-way ANOVAs were used to examine the effects of PL and TC on a range of self-monitoring measures. The results indicated that the higher proficiency learners made significantly fewer filled pauses, repetitions, and hesitations, and a higher ratio of error correction and error-free clauses than the lower proficiency learners. These results suggest that with the development of proficiency L2 learners’ performance becomes more fluent, and a more active and effective monitoring process seems to be at work. Compared to the single-task condition, performance in the dual-task condition led to significantly more repetitions implying the increased demand of TC triggers more dysfluency. These results are discussed in relation to the L1 monitoring models.