Anodal tDCS With Compensatory Audio-visual Training for Acquired Visual Field Defects After Brain Injury
- Conditions
- Hemianopsia, HomonymousStroke
- Registration Number
- NCT06116760
- Lead Sponsor
- Istituto Auxologico Italiano
- Brief Summary
Homonymous visual field defects (HVFDs) following acquired brain lesions affect independent living by hampering several activities of everyday life. Available treatments are intensive and week- or month-long. Transcranial Direct current stimulation (tDCS), a plasticity-modulating non-invasive technique, could be combined with behavioral trainings to boost their efficacy or reduce treatment duration. Some promising attempts have been made pairing occipital tDCS with visual restitution training, however less is knows about which area/network should be best stimulated in association with compensatory approaches, aimed at improving exploratory abilities, such as multisensory trainings.
In the present double-blind, sham-controlled study, we assess the efficacy of a multisensory training combined with tDCS. 3 groups of participants with chronic HVFDs underwent a 10-day (1.5 hrs/day) compensatory audio-visual training combined with either real anodal tDCS applied to the ipsilesional occipital tDCS (Group 1), or the ipsilesional posterior parietal cortex (Group 2), or a sham, placebo, tDCS (Group 3).
The training require the participants to orient their gaze training spatio-temporally congruent, cross-modal, audio-visual stimuli (starting from a central fixation) and press a button as quick as possible upon the detection of the visual stimulus. All stimuli are presented on 2mx2m panel embedded with 48 LEDs and loudspeakers (Bolognini et al., 2010, Brain Research)
All participants underwent a neuropsychological assessment of visuospatial functions prior to the beginning of the training (t0), at the end of the training (t1), and at 1-month (t2) and 4-month follow-up (t3). The assessment includes: a visual detection task, three visual search tasks (EF, Triangles, and Numbers; Bolognini et al., 2005, Brain), and a questionnaire about functional impact of the HVFDs in the activities of daily living.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 18
- Presence of chronic (>3 months) HVFD according to Neurophtalmological evaluation, due to acquired brain injury (i.e., stroke, traumatic brain injury, brain tumor)
- Presence of hemispatial neglect (indexed by pathological asymmetries on paper-and-pencil tests)
- Disorders of conjugated eye movements
- Other neurological disorders (e.g., dementia)
- Exclusion criteria for brain stimulation (i.e., epilepsy or family history of epilepsy; implanted electrodes, stimulators, pacemakers, infusion pumps, or any implanted metal device; pregnancy)
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Primary Outcome Measures
Name Time Method Change from baseline in Accuracy on the Triangle Task At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups Computerized visual search task. Participants have to report the number of triangles (targets) surrounded by square distractors. Accuracy: the proportion of correct responses (range 0-1).
Change from baseline in Accuracy on the EF Task At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups Computerized visual search task. Participants have to search for the target letter "F" surrounded by distractors "E"s. Accuracy: the proportion of correct responses (range 0-1).
Change from baseline in RTs on the Triangle Task At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups Computerized visual search task. Participants have to report the number of triangles (targets) surrounded by square distractors. RTs: median search times (seconds) of correct responses.
Change from baseline in the functional scale assessing the impact of vision loss in everyday life activities At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups A scale assessing the impact of HVFDs on nine activities of daily living. For each item, the score ranges from 0 ("No difficulty") to 4 ("Very frequent difficulties").
Change from baseline in RTs on the Numbers Task At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups Computerized visual search task. Participants have to point to numbers (1 to 15) in ascending order. RTs: median search times (seconds).
Change from baseline in Response Times (RTs) on the EF Task At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups Computerized visual search task. Participants have to search for the target letter "F" surrounded by distractors "E"s. RTs: median search times (seconds) of correct responses.
- Secondary Outcome Measures
Name Time Method Change from baseline in RTs on the Visual Detection Task At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups Detection of visual stimuli presented on the same panel employed for the training. RTs: median search times of the detected stimuli are calculated for both the sighted and the blind hemifields.
Change from baseline in Accuracy on the Visual Detection Task At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups Detection of visual stimuli presented on the same panel employed for the training. Accuracy (the proportion of detected stimuli; range 0-1) is calculated for both the sighted and the blind hemifields.
Trial Locations
- Locations (1)
Istituto Auxologico Italiano IRCCS
🇮🇹Milan, Lombardia, Italy
Istituto Auxologico Italiano IRCCS🇮🇹Milan, Lombardia, Italy