CATEGORICAL PERCEPTION The complicated Ba/Pa lecture…made simple by Alex and Nicole • Categorical perception: “this refers to our tendency to hear speech sounds ‘merely’ as members of a category—the category [b] sounds or the category of [p] sounds. More precisely, we are quite adept at hearing differences between categories but we are relatively insensitive to variations within the category.” • EXAMPLE: – We easily hear the difference between a [b] and a [p], but we are not able to distinguish a [p] and a [p]. – This is what the chart shows: • The white part is a B, and the black part is a P. if a sound falls in either side, we hear it as that letter. phonemes /ba/ /ba/ /pa/ /pa/ If you hear two sounds, and one falls on the black side and one on the white side, you hear it as two distinct categories, or two distinct letters. The spike represents the difference. b/b b/b b/b b/p p/p p/p p/p • This chart just shows that the p sounds differ in the different times that air is being released from your mouth. (you can have different gradients of the sound P by holding the air longer before releasing it, but you still hear it as a distinct P) THAT’S IT! On the left is the B the right is the P. Voice-Onset Time sound - 25ms 0 +25 +50 +75 R vs L • For English speakers, these are two distinct sounds. They would follow the black line on the chart above. • For Japanese speakers, these are not two distinct sounds, so these people perceive them as the SAME letter, no matter where they fall, and would follow the red line on the chart above. – This is because we are very sensitive to phonemes of our own language, but have a hard time distinguishing for other languages. R and L are distinct phonemes in the English language, but not the Japanese language. CONGRATULATIONS On becoming a soon-to-be father of two!!