What is it about snakes that makes people so jumpy and uncomfortable? There seem to be certain long-held and deeply human instincts, and Donald Norman’s Emotional Design (pp. 29-30) discusses how we can use these immediate affective responses–good and bad–in design. (A previous post about Emotional Design.)

What are the situations that trigger positive affect?

warm, comfortably lit places

temperate climate

sweet tastes and smells

bright, highly saturated hues

“soothing” sounds and simple melodies and rhythms

harmonious music and sounds


smiling faces

rhythmic beats

“attractive” people

symmetrical objects

rounded, smooth objects

“sensous feelings, sounds and shapes.

Meanwhile, the conditions that “appear to produce automatic negative affect”:


sudden, unexpected loud sounds or bright lights

“looming” objects (objects that appear to be about to hit the observer)

extreme hot or cold


extremely bright lights or loud sounds

empty, flat terrain (deserts)

crowded dense terrain (jungles or forests)

crowds of people

rotting smells, decaying foods

bitter tastes

sharp objects

harsh, abrupt sounds

grating and discordant sounds

misshapen human bodies

snakes and spiders

human feces (and its smell)

other people’s body fluids


Since I live in New York, I experience a lot of these latter triggers regularly. Can cities be designed to minimize these problems?

HT @davisk1000