Abstract
Neuroplasticity may be an important treatment target to improve the cognitive deficits in schizophrenia (SZ). Yet, it is poorly understood and difficult to assess. Recently, a visual high-frequency stimulation (HFS) paradigm that potentiates electroencephalography (EEG)-based visual evoked potentials (VEP) has been developed to assess neural plasticity in the visual cortex. Using this paradigm, we examined visual plasticity in SZ patients (N = 64) and its correlations with clinical symptoms, neurocognition, functional capacity, and community functioning. VEPs were assessed prior to (baseline), and 2-, 4-, and 20-min after (Post-1, Post-2, and Post-3, respectively) 2 min of visual HFS. Cluster-based permutation tests were conducted to identify time points and electrodes at which VEP amplitudes were significantly different after HFS. Compared to baseline, there was increased negativity between 140 and 227 ms for the early post-HFS block (average of Post-1 and Post-2), and increased positivity between 180 and 281 ms for the late post-HFS block (Post-3), at parieto-occipital and occipital electrodes. The increased negativity in the early post-HFS block did not correlate with any of the measures, whereas increased positivity in the late post-HFS block correlated with better neurocognitive performance. Results suggest that SZ patients exhibit both short- and long-term plasticity. The long-term plasticity effect, which was present 22 min after HFS, was evident relatively late in the VEP, suggesting that neuroplastic changes in higher-order visual association areas, rather than earlier short-term changes in primary and secondary visual cortex, may be particularly important for the maintenance of neurocognitive function in SZ.
Original language | English |
---|---|
Pages (from-to) | 39-45 |
Number of pages | 7 |
Journal | Schizophrenia Research |
Volume | 190 |
DOIs | |
State | Published - Dec 2017 |
Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2017
Funding
Funding for this study was provided by a Career Development Award (IK2 CX000844) to Dr. Jahshan from the United States (U.S.) Department of Veterans Affairs (VA), Clinical Sciences Research and Development Service. Additional support was provided by the VA Research Enhancement Award Program (REAP) (D1875-F) on Enhancing Community Integration for Homeless Veterans. The VA had no further role in study design; in the collection, analysis, and interpretation of data; in the writing of the report; and in the decision to submit the paper for publication. Funding for this study was provided by a Career Development Award ( IK2 CX000844 ) to Dr. Jahshan from the United States (U.S.) Department of Veterans Affairs (VA), Clinical Sciences Research and Development Service. Additional support was provided by the VA Research Enhancement Award Program ( REAP ) ( D1875-F ) on Enhancing Community Integration for Homeless Veterans. The VA had no further role in study design; in the collection, analysis, and interpretation of data; in the writing of the report; and in the decision to submit the paper for publication.
Funders | Funder number |
---|---|
Clinical Sciences Research and Development Service | |
REAP | D1875-F |
VA Research Enhancement Award Program | |
U.S. Department of Veterans Affairs | IK2CX000844 |
Shell United States |
Keywords
- EEG
- Neurocognition
- Neuroplasticity
- Schizophrenia
- VEP
- Visual plasticity