The Singers of Time

'''Pohl, Frederik, and Jack Williamson. The Singers of Time.''' New York: Doubleday, 1991. "A Foundation Book."

Some human characters have slots in their skulls for receiving "memo disks" that allow them to do highly technical work for aliens. See also for a species that divided into cultures spiritual and scientific on the one hand and high-tech and aggressive on the other. There are also two cyborgs of interest. Cf. H. G. Wells's The Time Machine (specifically mentioned on ST 352) and works dealing with mechanical "possession."

RDE, Title, 8Aug19