I believe I read it as part of a short story anthology in the late 1980s or the early 1990s, although it's likely older. The plot involves a crisis where people all over the world are suddenly going comatose, staring off into space. No one can figure out why until a researcher shows up, bearing a box of index cards that he occasionally talks to. He explains that television is the problem. The human brain retains all information and television, by flashing 60 frames every second, rapidly fills up that buffer, leaving no room for any more activity. I remember that he used the index cards to illustrate this to the President of the United States, convincing him that action needed to be taken. The story ended with the President beginning his speech, telling people they need to immediately shut off their TVs, and watching his image in the monitor, and then freezing up due to running out of storage. I believe that there was a picture on the last page of the president staring into the camera with a completely blank look on his face.
I think that the anthology also included a story involving a large-scale Maxwell's demon being used
as part of a building's heating and cooling system to answer "yes or no" questions about the future. I have, associated in my head, stories about a technology allowing one to discover all of one's ancestry from a drop of blood and a man learning that he's the only person without a single distinguished ancestor and another story where a man rejected for an insurance policy learns that it's because the computers have determined that the universe will cease to exist upon his death.