On January 13, 2000, Alvin Liberman died due to problems that occurred after heart surgery.
[7] His son Mark Liberman is Trustee Professor of Phonetics and director of the Institute for Research and Cognitive Science at the University of Pennsylvania.
His son M. Charles Liberman is Professor of Otology and Laryngology at Harvard Medical School.
[8] It was evident to Liberman that speech, the speed at which someone says something in particular, is connected to the word's amount of syllables, or in other terms its "acoustic complexity" (Whalen, 2000).
[9] The difference in the difficulty of speech and reading exists even as alphabetic writing systems provide discrete and invariant signals and nods to vowels, sounds and consonants.
Human listeners are able to decode the repetitive variable signal of running speech and to translate it into phonemic components.
Liberman ascribed this to the human biological disposition towards speech as opposed to reading which is not ingrained genetically.
In one of his articles, Liberman mentioned speech production is easy to create as it relies on the "conscious awareness of phonological structure".
[11] He disagreed with "horizontal theory" because it would imply that the "advantage of ease" would be dependent upon reading and writing, not speech.
Liberman discovered that children who fail to learn to read on schedule lack phonemic awareness.