McLuhan

the wheel
is an extension of the foot
the book
is an extension of the eye
clothing, an extension of the skin,
electric circuitry,
an extension of
the
central
nervous
system

The Medium is The Massage, Marshall McLuhan p 31-40

As youth enters this clan world and all their senses are electrically extended and intensified, there is a corresponding amplification of their sexual sensibilities.

From “The Playboy Interview: Marshall McLuhan�, Playboy Magazine, March 1969. © Playboy

…[I]f a new technology extends one or more of our senses outside us into the social world, then new ratios among all of our senses will occur in that particular culture… And when the sense ratios alter in any culture then what had appeared lucid before may suddenly become opaque, and what had been vague or opaque will become translucent.

Marshall McLuhan, “The Gutenberg Galaxy: The Making of Typographic Man”, 1962.