There are 5 sound files...
VERY HAPPY ``a hoo hoo hoo hoooo, wheeeeee''
HAPPY ``That's what Tigger's like best!''
NEUTRAL <silent>
UNHAPPY <growls> ``woraworawora''
VERY UNHAPPY (pro-actively sad) `Stop that kid please S-T-O-P stop'
SHUT DOWN MODE <silent>
Voices convey emotion not just through words themselves, but through intonation-rising and falling pitch, variation in rhythm, volume, and intensity... By seven months they appear to connect facial expressions with tones of voice... [Sigman and Capps, 1997].
Surprisingly little work has been done on infants' perception of emotion in vocal expression. What work there is suggests that discrimination of vocally expressed emotion appears somewhat earlier than discrimination of facial emotions... This, however, rather than indicating a limitation of young infants' ability, suggests that they are well tuned to pick up emotion in situations that approximate more to real life, in which emotion is typically conveyed by tone of voice as well as facial expression [Bremner, 1994].
Piaget's resorting to verbal report as the indicator of `internalization' may or may not have been accurate[Piaget, 1981]. While two and three year olds have a large vocabulary, the imitation dilemma may also persist in language acquisition. Bretherton and Beeghly (1982) note that children as young as two years of age use terms that refer to mental states, with references to self states as somewhat ahead of references to the states of others. This is significantly earlier than the seven year old that Piaget claims is just beginning to verbalize their emotional lexicon.