Canadian Neurological Society (CNS) About the CNS Society Application Form. First-year residents, 1st year membership is free. Canadian Association of Child Neurology (CACN) About the CACN Society Application Form. First-year residents, 1st year membership is free. Canadian Neurosurgical Society (CNSS) About the CNSS Society Application Form. First-year residents, 1st year membership is free. Canadian Society of Clinical Neurophysiologists (CSCN) About the CSCN Society Application Form. First-year residents, 1st year membership is free.