This study aims to investigate whether a specific brain region mediates the cognitivedeficit in long COVID brain fog, and whether targeted modulation of this region canimprove cognition.In observational study, the objective was to identify potential intervention targets forpatients with long COVID brain fog. A total of 120 patients with long COVID wereenrolled. Brain fog (BF) severity was quantified using the Brain Fog Assessment (BFA).Participants completed a continuous random-dot motion (cRDM) task during 128-channelelectroencephalography (EEG) and underwent structural MRI and standardizedneuropsychological testing.In interventional study, 40 participants with persistent BF symptoms were enrolled fortranscranial ultrasound stimulation (TUS). On Day 1, participants completed the BFA andprovided demographic data, then performed the baseline cRDM task; 20 minutes later,structural MRI and baseline resting-state MRI were acquired. On Day 2, participantsreceived 60 seconds of TUS (active or sham) according to randomized allocation. Twentyminutes post-stimulation, an 8-minute resting-state MRI scan was obtained, followedimmediately by the follow-up cRDM task.
Not Provided
Device: sham transcranial ultrasound stimulation
In the sham group, the transducer power was turned off, pre-recorded pulse repetition
sounds were played to control for auditory confounds. The equipment appearance is
consistent with the test device. Single stimulation, 60 seconds.
Device: real transcranial ultrasound stimulation
Ultrasound stimulation was delivered using TPO-203 and H-104MR_4AA-4CH transducer (Sonic
Concepts, Woodinville, WA, USA). In the real stimulation group, theta-burst TUS (Yaakub
et al., 2024; Yaakub et al., 2023) was performed with the following parameters: pulse
duration = 20 ms; pulse repetition interval = 200 ms; total duration = 80 s. The target
free-field spatial peak pulse-average intensity was maintained at 33.85 W/cm². The
stimulation target was defined as the overlapping region between the source localisation
results and the right inferior insula in the Destrieux atlas
Inclusion Criteria:
- Patients should have a history of COVID-19 infection (positive test results for
either polymerase chain reaction or rapid antigen test) and report persistent brain
fog (BF) symptoms at least 4 weeks after recovering from acute COVID-19.
Exclusion Criteria:
- 1. Presence of any symptoms of cognitive impairment or other neurological symptoms
prior to COVID-19 infection;
- 2. Structural MRI revealing significant intracranial lesions or structural
abnormalities;
- 3. Development of severe neurological complications after COVID-19 infection,
including delirium, cerebrovascular diseases, encephalitis, and epilepsy;
- 4. Other disorders that may cause cognitive impairment, including Dementia,
Schizophrenia spectrum disorders, stroke, Alzheimer's disease, and Parkinson's
disease.
Xuanwu Hospital, Capital Medical University
Beijing, Beijing Municipality, China
Shandong Daizhuang Hospital
Jining, Shandong, China
Yi Tang, MD., PhD
00861083198673
tangyi@xwhosp.org
Shaojiong Zhou, MD.
shaojiongzhou@sina.com
Yi Tang, MD., PhD, Principal Investigator
Xuanwu Hospital, Beijing