Effect of Memantine on ERP in Early Schizophrenia and Healthy Subjects
Status:
Unknown status
Trial end date:
2016-12-01
Target enrollment:
Participant gender:
Summary
Patients with schizophrenia are deeply affected by the positive symptoms, negative symptoms
and cognitive impairment. A generalized cognitive deficit could be frequently observed and
traced back to early stage of the disease. Currently medication intervention significantly
improves positive symptoms through dopamine receptor modification, leaving alone the negative
symptoms and cognitive impairment. Besides dopamine dysregulation, more and more attention
had been paid to the association of N-methyl-D-aspartate (NMDA) type glutamate receptor and
schizophrenia, focusing on the neurobiological and cognitive biomarkers change. Memantine, an
uncompetitive antagonist of NMDA type glutamate receptor approved as cognitive enhancer for
Alzheimer's disease, is a potential candidate for preventing cognitive decline of
schizophrenia. Previous randomized clinical trials failed to demonstrate its efficacy on
chronic schizophrenic patients and it might be related to the chronic and irreversible
disease process. There is also study supporting that memantine induces change in mismatch
negativity (MMN) in frontal cortex of healthy subjects. This study will compare the MMN
change of healthy subjects and the population of early schizophrenia, who has persistent
neurobiological, cognitive biomarkers or negative symptoms despite subsided positive
symptoms. Both male and female aged 20-45 years old outpatients with a length of illness for
less than 5 years since first diagnosed as schizophrenia, currently receiving treatment by
atypical antipsychotics in a relatively stable condition will be recruited. Healthy subjects
will be recruited comparing their age and sex. We plan to recruit 10 subjects for both
patient and healthy subjects with a total of 20 participants. All participants will receive
general clinical, cognitive and event-related potential (ERP) evaluation as baseline before
taking medication. Twenty mg of memantine will be given 4 hours before ERP retest. The
analyses will be performed based on the change of ERP using paired-t sample test. Baseline
clinical and cognitive symptoms will be analyzed as possible confounders.