Solid-state image pickup element having a control circuit for controlling the operation period of a transfer circuit and method for controlling the same

A transfer circuit is configured to transfer signal charges of an accumulating region to a floating diffusion region when being operated, while being configured to stop the transfer of the signal charges when not being operated, by use of a transfer gate which is turned on and off in response to a transfer control signal. The pixel control circuit controls the transfer circuit according to a light receiving level of a pixel circuit so as to extend an operation period of the pixel circuit in a case where a light receiving quantity is not lower than a predetermined quantity, contrary to a case where the light receiving quantity is lower than the predetermined quantity.