There are several major circuit boards that process Pleo's sensors and respond with motor control and speech. There are actually five boards in this image. Three of them are soldered together in his front torso.
There are several Fairchild Semiconductor FAN8100N motor controllers scattered throughout the robot.
Here, as well as on the I/O board in the torso, are 48-pin Toshiba TMP86FH47AUG 8-bit microcontrollers with the markings 06502AI41 F1015M04.