Age-related differences in SSVEP-based BCI performance

Brain–Computer Interface (BCI) systems analyze brain signals to generate control commands for computerapplications or external devices. Utilized as alternative communication channel, BCIs have the potential toassist people with severe motor disabilities to interact with their environment and to participate in dailylife activities. Handicapped people from all age groups could benefit from such BCI technologies. Althoughsome papers have previously reported slightly worse BCI performance by older subjects, in many studiesBCI systems were tested with young subjects only.In the presented paper age-associated differences in BCI performance were investigated. We comparedaccuracy and speed of a steady-state visual evoked potential (SSVEP)-based BCI spelling application controlled by participants of two different equally sized age groups. Twenty subjects (eleven female and ninemale) participated in this study; each age group consisted of ten subjects, ranging from ۱۹ to ۲۷ yearsand from ۶۴ to ۷۶ years. Our results confirm that elderly people may have a deteriorated informationtransfer rate (ITR). The mean (SD) ITR of the young age group was ۲۷.۳۶ (۶.۵۰) bit/min while the elderly people achieved a significantly lower ITR of ۱۶.۱۰ (۵.۹۰) bit/min. The average time window lengthassociated with the signal classification was usually larger for the participants of advanced age. Thesefindings show that the subject age must be taken into account during the development of SSVEP-basedapplication