What?

Processing of sensory signals (sounds, images,…)

– information about outside world– perceived and processed by human cognitive system– sometimes produced by human beings for use in human

communication (speech, gestures, graphical symbols, writing,…)

Describe the signal, so that it can be– stored and/or efficiently transmitted and reconstructed– modified and reconstructed– used for extraction of information…..

How?

• That is what this class is about• physiology of sensory organs• psychophysics of perception• emulation of the knowledge in engineering

• The most important question

WHY ?

In the South Seas there is a cargo cult of people. During the war they saw airplanes with lots of good materials, and they want the same thing to happen now. So they've arranged to make things like runways, to put fires along the sides of the runways, to make a wooden hut for a man to sit in, with two wooden pieces on his head to headphones and bars of bamboo sticking out like antennas--he's the controller--and they wait for the airplanes to land. They're doing everything right. The form is perfect. It looks exactly the way it looked before. But it doesn't work. No airplanes land.

In a similar way, cargo cult scientist follows all the apparent precepts and forms of scientific investigation, but the planes don't land.

adopted from Richard Feynman, Caltech Commencement 1974

WHY ?

• Why should we care how are the cognitive signals processed in biology?

original flipped reversed

double power (1.4 amplitude)

eight times power (2.8 amplitude)

power-law of perception

percept=stimulus r

r = 0.33 for hearing

acoustic /ba/ and visual /ga/ yields /da/ or /tha/

“bad” engineering perceived

good engineering perceived as

perception

engineering

good engineering could be consistent with biology• physiology of sensory organs• psychophysics of perception• emulation of the knowledge in engineering

cognitive signal

effect ( signal )

effect ( signal )

Should Airplanes Flap Wings ? (And should machines have eyes and ears?)

How should we proceed ?

homework

• Why do I want to take this class