The implantable medical device is configured as a cochlear implant or the like. The device activated by the user speaking a keyword. Because the light condensed by the microlens array is incident at the optical fiber cores corresponding to the microlenses, the light can be efficiently incident. This planned power supply process is performed. In some embodiments, the connector members can be engageddisengaged by rotating an element of the coupling mechanism. In some embodiments, the apparatus is enabled to deliver an appetite suppressant to modify the eating behavior.