Electronic device with foveated display system

An electronic device may have a display. A gaze detection system may gather information on a user's point of gaze on the display. Based on the point-of-gaze information, control circuitry in the electronic device may produce image data for an image with areas of different resolutions. A full-resolution portion of the image may overlap the point of gaze. Lower resolution portions of the image may surround the full-resolution portion. The display may have a pixel array. The pixel array may include rows and columns of pixels. Data lines may be used to supply data to the columns of pixels in accordance with row selection signals supplied to the rows of pixels. Display driver circuitry may be used to display the image using the pixel array. The display driver circuitry may have row selection circuitry and column expander circuitry that are responsive to a resolution mode selection signal.