An electronic device may have a display and a gaze tracking system. The electronic device may display images on the display that have a higher resolution in a portion of the display that overlaps a gaze location than other portions of the display. Timing controller circuitry and column driver circuitry may include interpolation and filter circuitry. The interpolation and filter circuitry may be used to perform nearest neighbor interpolation and two-dimensional spatial filtering on low resolution image data. Display driver circuitry may be configured to load higher resolution data into selected portions of a display. The display driver circuitry may include low and high resolution image data buffers and configurable row driver circuitry. Block enable transistors may be included in a display to allow selected blocks of pixels to be loaded with high resolution image data.