Figure 6.

Experiments 2&3: Omitting and manipulating statistics. (a) Experiment 2a: Synthesis with the full set of statistics is preferred over synthesis omitting any single class. In condition 1, the envelope mean was imposed, to ensure that the spectrum was approximately correct. Asterisks here and in (b) and (d) denote significant differences from chance or between conditions, p<.01. (b) Experiment 2b: Sounds with the correct cochlear marginal statistics were preferred over those with 1) the cochlear marginal moments of noise, 2) all cochlear marginals omitted (as in cond. 1 of (a)), or 3) the skew and kurtosis omitted. (c) Frequency responses of logarithmically and linearly spaced cochlear filter banks. (d) Experiment 3: Sounds synthesized with a biologically plausible auditory model were preferred over those synthesized with models deviating from biology (by omitting compression, or by using linearly spaced cochlear or modulation filter banks).