Eye movements reveal a similar Positivity Effect in Chinese and UK older adults

The “positivity effect” (PE) reflects an age-related increase in the preference for positive over negative information in attention and memory. The present experiment investigated whether Chinese and UK participants produce a similar PE. In one experiment we presented pleasant, unpleasant and neutral pictures simultaneously and participants decided which picture they liked or disliked on a third of trials respectively. We recorded participants’ eye movements during this task and compared time looking at, and memory for, pictures. The results suggest that older but not younger adults from both China and UK participant groups showed a preference to focus on and remember pleasant pictures, providing evidence of a PE in both cultures. Bayes Factor analysis supported these observations. These findings are consistent with the view that older people preferentially focus on positive emotional information, and that this effect is observed cross-culturall

Participant Feedback in the Evaluation of Novel Stroke Rehabilitation Technologies

Purpose: Stroke participant perspectives are used to evaluate a novel rehabilitation system employing electrical stimulation (ES) technology combined with robotic assistance and virtual reality. The broader implications of such feedback for future technological development are discussed. Method: While supported by a robot, ES was applied to the triceps and anterior deltoid muscles of 5 chronic stroke participants with upper limb impairment to assist them in completing functional, virtual reality tracking tasks. Advanced ES controllers adjusted the amount of ES applied on each attempt to improve accuracy and maximise voluntary effort. The system was evaluated in terms of participants’ perspectives, expressed during a semi-structured interview, and clinical outcome measures. Results: The rehabilitation system was well accepted by participants and viewed positively, despite mixed opinions regarding effectiveness. Feedback demonstrated an alignment in participants’ perceptions of reduced impairment and clinical outcomes, in which a significant (p < 0.001) mean change of 9.3 in Fugl-Meyer scores was observed. Participant feedback also provided insight into individual differences observed in clinical outcomes. From our findings six key issues regarding effectiveness, muscles trained, system flexibility and portability, possible discomfort and the value of participant perspectives emerged that may be relevant for researchers developing new rehabilitation technologies. Conclusion: Participant feedback via a semi-structured interview provided important insight into the usability and effectiveness of using this system as a platform for upper limb stroke rehabilitation

Upper limb and eye movement coordination during reaching tasks in people with stroke

Purpose: To enhance understanding of the relationship between upper limb and eye movements during reaching tasks in people with stroke. Methods: Eye movements were recorded from 10 control participants and 8 chronic stroke participants during a visual orienting task (Experiment 1) and a series of reaching tasks (Experiment 2). Stroke participants completed the reaching tasks using (i) their less impaired upper limb, (ii) their more impaired upper limb without support, and (iii) their more impaired upper limb, with support (SaeboMAS gravitational support and/or electrical stimulation). Participants were tested individually and completed both experiments in the same session. Results: Oculomotor control and the coordination between the upper limb and the oculomotor system were found to be intact in stroke participants when no limb movements were required, or when the less impaired upper limb was used. However, when the more impaired upper limb was used, success and accuracy in reaching decreased and patterns of eye movements changed, with an observed increase in eye movements to the limb itself. With upper limb support, patterns of hand-eye coordination were found to more closely resemble those of the control group. Conclusion: Deficits in upper limb motor systems result in changes in patterns of eye movement behavior during reaching tasks. These changes in eye movement behavior can be modulated by providing upper limb support. -Implications for Rehabilitation -Deficits in upper limb motor systems can result in changes in patterns of eye movement behavior during reaching tasks. -Upper limb support can reduce deficits in hand-eye coordination. -Stroke rehabilitation outcomes should consider motor and oculomotor performance

Lateralisation of spatial processing and age

Studies assessing spatial ability suggest right hemisphere specialisation for coordinate spatial processing and left hemisphere specialisation for categorical spatial processing. With regard to healthy ageing, spatial abilities may be affected selectively, with right hemisphere based coordinate processes being more vulnerable to age-related decline, but previous research has been inconsistent. In the present study, age and hemispheric specialisation of categorical and coordinate spatial abilities were explored. Testing 56 right-handed younger and older participants clearly showed a left hemisphere advantage for the categorical task and a right hemisphere advantage for the coordinate spatial task, for both age groups combined. Older adults were slower to process information and make a spatial judgement; nevertheless, the neural specialisation underlying spatial abilities seems to have remained consistent with ag

Eye movements during visuospatial judgements

The goal of the current research was to determine whether eye movements reflect different underlying cognitive processes associated with visuospatial relation judgements. Ten participants made three different judgements regarding the position of a dot in relation to a bar; an above/below judgement, a near/far judgement, and a precise distance estimation. The results highlight similarities between above/below and near/far visuospatial judgements; specifically, such binary judgements were fast, reflexive and did not require precise distance computation. In contrast, estimating distance was comparatively cognitively demanding and required precise distance computation, as evidenced through distinct scan paths. The eye movement data provide significant insight into the cognitive processes underlying visuospatial judgements, showing aspects of visuospatial processing that are similar, as well as those that differ between task

Eye movement measures and associated ANOVA results.

<p>Eye movement measures and associated ANOVA results.</p

Stimulus photograph used in the present study.

<p>Stimulus photograph used in the present study.</p

Measures for recognition and relocation tasks and associated ANOVA results.

<p>Measures for recognition and relocation tasks and associated ANOVA results.</p

Iterative learning control in healthcare electrical stimulation and robotic-assisted upper limb stroke rehabilitation

Annually, 15 million people worldwide suffer a stroke, and 5 million are left permanently disabled. A stroke is usually caused when a blood clot blocks a vessel in the brain and acts like a dam, stopping the blood reaching the regions downstream. Alternatively, it may be caused by a hemorrhage, in which a vessel ruptures and leaks blood into surrounding areas. As a result, some of the connecting nerve cells die, and the person commonly suffers partial paralysis on one side of the body, termed hemiplegia. Cells killed in this way cannot regrow, but the brain has some spare capacity and, hence, new connections can be made. The brain is continually and rapidly changing as new skills are learned, new connections are formed, and redundant ones disappear. A person who relearns skills after a stroke goes through the same process as someone learning to play tennis or a baby learning to walk, requiring sensory feedback during the repeated practice of a task. Unfortunately, the problem is that they can hardly move and, therefore, do not receive feedback on their performance