Poster Session 04 Program Schedule
02/15/2024
12:00 pm - 01:15 pm
Room: Majestic Complex (Posters 61-120)
Poster Session 04: Neuroimaging | Neurostimulation/Neuromodulation | Teleneuropsychology/Technology
Final Abstract #101
Personalized Remote HD-tDCS Improves Cognition Following Carbon Monoxide Poisoning Induced Amnesia: a Case Report
Brett Schneider, University of Michigan, Ann Arbor, United States
Melvin McInnis, University of Michigan, Ann Arbor, United States
Victor Di Rita, University of Michigan, Ann Arbor, United States
Benjamin Hampstead, University of Michigan, Ann Arbor, United States
Category: Neurostimulation/Neuromodulation
Keyword 1: amnesia
Keyword 2: neuromodulation
Keyword 3: neurostimulation
Objective:
High-definition transcranial direct current stimulation (HD-tDCS) has the potential to improve cognitive functioning in age-related decline, acquired brain injuries, and in neurodegenerative conditions. In this case report, we present the first HD-tDCS intervention in a participant with severe anterograde amnesia following carbon-monoxide poisoning. We used advanced methodological techniques to perform a patient-centered, remote administration of HD-tDCS. We also integrated functional near infrared spectroscopy (fNIRS) to assess the neurophysiological effects of stimulation.
Participants and Methods:
Participant 60 (PT60) was a 55-year-old, right-handed, White male with 16 years of education who suffered chronic, severe anterograde amnesia following carbon monoxide poisoning due to a suicide attempt. PT60 was referred to our research group 6 months post injury with the goal of improving his ability to form new memories. We identified the key brain regions involved in memory encoding using automated meta-analyses (Neurosynth), which included the left frontoparietal network (FPN). We then used finite element modelling of the participant’s structural MRI to develop an individualized electrode montage that targeted this network. The participant underwent two rounds (Round 1 = 31 sessions and Round 2 = 30 sessions) of HD-tDCS separated by 3 months. HD-tDCS was delivered for 20 minutes per session with two anodes (one over lateral prefrontal and one over superior parietal cortex) delivering 3 mA each (6 mA total). The first 5 sessions were performed in person but all others were performed in home under the videoconference supervision of research staff. He underwent objective cognitive assessment 10 days after injury (Clinical Evaluation), and pre and post Round 1 and Round 2 (5 total timepoints including the clinical evaluation) using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). We calculated reliable change indices (RCI) to evaluate significant changes in cognitive performance between each interval to evaluate the effectiveness of stimulation on memory and cognition. To assess the neurophysiological effects of HD-tDCS, we assessed changes in brain oxygenation during memory encoding during two memory tasks (Object Location Test and Face Name task) Pre and Post Round 2. We then compared the task-related blood oxygenation changes during task performance to assess for “activity” changes following stimulation.
Results:
Overall, the participant’s objective cognitive functioning, particularly immediate memory, improved significantly following Round 1, declined during the 2 months without HD-tDCS, and again improved following Round 2. Subjective informant reports from family and medical personnel followed this same pattern of improvement following each round with a decline in-between rounds. We also demonstrated preliminary evidence for increased brain “activity” during a learning/memory task within the FPN and decreased brain “activity” in contralateral prefrontal areas.
Conclusions:
Overall, this case report demonstrates how a user-friendly, personalized approach to HD-tDCS has potential in enhancing cognition following anoxic/hypoxic brain injury.
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