This study investigates the potential of passive finger movements as an alternative to motor imagery (MI) for the calibration of brain-computer interfaces (BCIs). Twenty-six participants performed both MI tasks and passive movement tasks involving finger flexion and extension, while their electroencephalographic (EEG) brain activity was recorded and analyzed. Brain activity in the α (8–12 Hz) and β (20–25 Hz) bands was significantly stronger during passive movement tasks compared to MI tasks. Additionally, task conditions and movement types had independent and significant effects. These findings suggest that passive movements could improve the accessibility and reliability of BCIs, particularly in applications requiring precise finger control such as extended reality applications.