Such "hidden" hearing loss, not evident in the audiogram (a test that measures hearing sensitivity), is also apparent in human listeners who experience persistent tinnitus, but otherwise normal sensitivity.

BBC: Viewpoint: Does deafness contribute to dementia?

When managers managed with a spreadsheet rather than real-world knowledge about what was actually going on in the factory and what were its possibilities, they overlooked hidden costs of the erosion of skills, the loss of quality and constraints on innovation.

FORBES: Why Apple and GE Are Bringing Back Manufacturing

When managers manage with a spreadsheet rather than real-world knowledge about what is actually going on in the factory and what were its possibilities, they overlook hidden costs of the erosion of skills, the loss of quality and constraints on innovation.

FORBES: The Boeing Debacle: Seven Lessons Every CEO Must Learn