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

NCT06116760 | Completed

• 1 other identifier: 25C901
• Study Type: interventional
• Target: 18
• Locations: 1 country
• Sites: 1

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.

Conditions

Stroke; Hemianopsia, Homonymous

Keywords

Homonymous Visual Field Defects; Hemianopia; Compensatory training; Audio-visual multisensory training; tDCS

Outcome Measures

Primary Outcomes (6)

• 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

• 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

• 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

• 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

• 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

• 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 Outcomes (2)

• 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

• 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

Study Arms (3)

Anodal Occipital tDCS + audio-visual training

EXPERIMENTAL

Anodal tDCS on ipsilesional occipital cortex. Anode electrode placed on O1/O2 (10-20 EEG system) and reference electrode placed on the contralateral forehead. Stimulation delivered at 2mA during the first 30 minutes of the audio-visual training.

Device: Anodal or sham tDCS; Behavioral: Audio-visual training

Anodal Parietal tDCS + audio-visual training

EXPERIMENTAL

Anodal tDCS on ipsilesional posterior parietal cortex. Anode electrode placed on P3/P4 (10-20 EEG system) and reference electrode placed on the contralateral forehead. Stimulation delivered at 2mA during the first 30 minutes of the audio-visual training.

Device: Anodal or sham tDCS; Behavioral: Audio-visual training

Sham tDCS + audio-visual training

SHAM COMPARATOR

Arm 3: sham tDCS. Half of participants with Group 1 montage, the other half with Group 2 montage. Stimulator is turned off after 30s of the audio-visual training.

Device: Anodal or sham tDCS; Behavioral: Audio-visual training

Interventions

Anodal or sham tDCS DEVICE

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

Anodal Occipital tDCS + audio-visual training; Anodal Parietal tDCS + audio-visual training; Sham tDCS + audio-visual training

Audio-visual training BEHAVIORAL

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, 8Ω) 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.

Anodal Occipital tDCS + audio-visual training; Anodal Parietal tDCS + audio-visual training; Sham tDCS + audio-visual training

Eligibility Criteria

• Age: 18 Years - 90 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

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

You may not qualify if:

• Presence of hemispatial neglect (indexed by pathological asymmetries on paper-and-pencil tests)
• Disorders of conjugated eye movements
• Other neurological disorders (e.g., dementia)

Sponsors & Collaborators

• Istituto Auxologico Italiano: lead

Study Sites (1)

Istituto Auxologico Italiano IRCCS

Milan, Lombardy, 20122, Italy

Location

Related Publications (3)

• 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.

  PMID: 16219672 BACKGROUND

• 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.

  PMID: 20599813 BACKGROUND

• Diana L, Casati C, Melzi L, Marzoli SB, Bolognini N. Enhancing multisensory rehabilitation of visual field defects with transcranial direct current stimulation: A randomized clinical trial. Eur J Neurol. 2025 Jan;32(1):e16559. doi: 10.1111/ene.16559. Epub 2024 Nov 28.

  PMID: 39607286 DERIVED

MeSH Terms

Conditions

Stroke; Hemianopsia

Condition Hierarchy (Ancestors)

Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Vision Disorders; Sensation Disorders; Neurologic Manifestations; Blindness; Eye Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Masking Details: The tDCS device has a built-in function for double blind studies, i.e., the experimenters are not aware whether they are applying real or sham tDCS.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Three groups of participants were allocated to three different experimental treatments: Group 1: audio-visual training + ipsilesional occipital tDCS Group 2: audio-visual training + ipsilesional posterior parietal tDCS Group 3: audio-visual training + sham, placebo tDCS

Study Record Dates

• First Submitted: October 31, 2023
• First Posted: November 3, 2023
• Study Start: January 1, 2016
• Primary Completion: December 31, 2023
• Study Completion: December 31, 2023
• Last Updated: March 12, 2024

Record last verified: 2024-03

Data Sharing

• IPD Sharing: Will share
• Time Frame: Upon the publication of the study
• Access Criteria: Access to data will be granted upon request

Locations

IT (1)