Anodal tDCS With Compensatory Audio-visual Training for Acquired Visual Field Defects After Brain Injury

Stroke Clinical Trial

Official title:

Anodal tDCS With Compensatory Audio-visual Training for Acquired Visual Field Defects After Brain Injury

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT06116760
• Other study ID #: 25C901
• Status: Completed
• Phase: N/A
• Start date: January 1, 2016
• Est. completion date: December 31, 2023

Study information

• Verified date: March 2024
• Source: Istituto Auxologico Italiano
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial 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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 18
• Est. completion date: December 31, 2023
• Est. primary completion date: December 31, 2023
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 90 Years

Eligibility

Inclusion Criteria:

• Presence of chronic (>3 months) HVFD according to Neurophtalmological evaluation, due to acquired brain injury (i.e., stroke, traumatic brain injury, brain tumor)

Exclusion Criteria:

• 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)

Related Conditions & MeSH terms

• Brain Injuries
• Hemianopsia
• Hemianopsia, Homonymous
• Stroke

Intervention

Device:
• Anodal or sham tDCS
Anodal or sham tDCS (see "Arms") is applied during the execution of an audio-visual training.

Behavioral:
• Audio-visual training
90 min/day x 10 days. Participants are seated in front of a 2 m × 2 m training board, at a distance of 1.2 m, in a dimly lit room. The board features 48 red light-emitting diodes (LED, diameter 1 cm, luminance 90 cd m2), distributed in six horizontal rows (eight lights per row). Forty-eight piezoelectric loudspeakers (0.4 W, 8O) are located above each light, producing a white-noise (80 dB, duration 100 ms). Spatio-temporally congruent, cross-modal, audio-visual stimuli are presented at one out of 48 possible positions on the board. Participants are instructed to look at the fixation point - at the center of the apparatus - and to move their eyes to detect the presence of the visual stimulus (duration=100 ms) by pressing right button of a wireless mouse.

Locations

Country	Name	City	State
Italy	Istituto Auxologico Italiano IRCCS	Milan	Lombardia

Sponsors (1)

Lead Sponsor	Collaborator
Istituto Auxologico Italiano

Country where clinical trial is conducted

Italy, 

References & Publications (2)

Bolognini N, Fregni F, Casati C, Olgiati E, Vallar G. Brain polarization of parietal cortex augments training-induced improvement of visual exploratory and attentional skills. Brain Res. 2010 Aug 19;1349:76-89. doi: 10.1016/j.brainres.2010.06.053. Epub 2010 Jul 1. — View Citation

Bolognini N, Rasi F, Coccia M, Ladavas E. Visual search improvement in hemianopic patients after audio-visual stimulation. Brain. 2005 Dec;128(Pt 12):2830-42. doi: 10.1093/brain/awh656. Epub 2005 Oct 11. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change from baseline in Accuracy on the EF Task	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).	At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups
Primary	Change from baseline in Response Times (RTs) on the EF Task	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.	At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups
Primary	Change from baseline in Accuracy on the Triangle Task	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).	At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups
Primary	Change from baseline in RTs on the Triangle Task	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.	At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups
Primary	Change from baseline in RTs on the Numbers Task	Computerized visual search task. Participants have to point to numbers (1 to 15) in ascending order. RTs: median search times (seconds).	At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups
Primary	Change from baseline in the functional scale assessing the impact of vision loss in everyday life activities	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").	At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups
Secondary	Change from baseline in Accuracy on the Visual Detection Task	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.	At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups
Secondary	Change from baseline in RTs on the Visual Detection Task	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.	At baseline (at the beginning of the treatment), at the end of the treatment, at 1- and 4-month follow-ups