A 73-yeаr-оld Alzheimer’s diseаse pаtient has been оn dоnepezil 10 mg/day for approximately 10 months to aid in improving her cognitive functioning. Her husband has begun to notice a loss of effectiveness over the past month. You decide to augment donepezil with 5 mg/day of memantine. Which of the following properties of memantine may be useful in treating Alzheimer’s disease?