USC dyslexia project speech perception experiments (cont.)  STILL IN PROGRESS!!


Here are the scripts, sound files, and picture files for the experiments run in Matlab.  Sound files are in .wav format.

These materials are posted here for the convenience of project members; others please do not use without first asking either or



Zip of some functions used by multiple scripts below.

Experiment 1 (spy-sky continuum identification and discrimination; this is the same as the Psyscope version of spy-sky but with the addition of discrimination of the long transition stimuli, and between-block reinforcements “advance to next level”).  Stimuli differ as short (45 ms) vs. long (95 ms) transition durations and by F2 onset frequency (1100 to 1800 Hz).

    zip of whole thing including Matlab scripts, sound files, picture files

    zip of just sound files (.wav): ignore first 2 characters in names, then 45=short and 95=long, then last 2 digits of name are first 2 digits of F2 onset frequency, e.g. S14511 = short transition, 1100 Hz F2 onset

    zip of just picture files (.jpg): spysky, skyspy, congrats, level1, level2, level3, level4, level5, level6


Experiment 2 (identification in noise of endpoint synthetic short-transition spy-sky stimuli, naturally-spoken spy and sky, and two environmental sounds, clapping and stream; many SNRs have been made for piloting but any one script uses only a few of them)

    zip of scripts for Nov. 28 version of experiment  


  zip of all picture files (only clap and stream are new, others are same as Exp1)
    zip of all sound files (table shows all combinations made and some sample filenames, but files are available only all together; stimuli called “clear” are originals normalized-equalized to nominal 80 dB)



spy or sky


spy or sky


clap or stream































































































Experiment 3 (draft) (tone detection in noise by adaptive staircase procedure; there are no sound files because tone, noise, and their combination are all generated by the script during the experiment; and no picture files)


zip of script and functions (draft)

Experiment 4 (gating).  There are no picture files for this experiment.


Matlab script (includes a parameter for omitting short gates in practice and/or test items)

list.txt file

zip of sound files (all gates)

Experiment 5 (draft) (target word recognition under several variability conditions, final items not yet determined)


Matlab script

list.txt file

zip of all sound files (for all conditions, possibly some extras as well)

zip of all picture files (screen displays used in running experiment)

Experiment 5a (draft) (subset of above with only conditions 0 and 1, testing one vs. multiple speakers)  Still to come: audio hints about the identity of target words, to eliminate mis-hearings by subjects.

This experiment's scripts (both versions) include 2 features intended to speed up RTs, which were far too long in initial pilot: variable ISI so that subjects cannot set up a rhythm of responses, and an on-screen display of a time bar which shows time remaining to an arbitrary deadline for response (which in fact is not enforced).  Together these features do encourage subjects to respond quickly.  There are no picture files for stimuli in this experiment.

Experiment 5sh (extension of 5a that adds items comparing same vs. different allophones by the same vs. different speakers).  This version includes an audio hint for each target word, and the on-screen time bar.  There are 2 versions of the experiment, 1 and 2, which counterbalance the one-speaker vs. multi-speaker conditions.  Each version has its own script and file list, but uses the same sound and picture files.

           Matlab script 1 and script 2
            list1 and list 2
            zip of all sound files (including prompt files)
            (zip of pictures files is same as above though not all are used in this version)
            zip of the whole thing

Experiment 6 (segments vs features) (with the original script this experiment failed in that the expected basic RT effect that it builds on was not obtained - all RTs were far too long; see above for speeding up RT - this is why there are 2 versions of the script; the second version has not yet been tested)


original Matlab script


Matlab script incorporating countdown bar
          list.txt file

zip of all sound files

zip of all picture files



created by P. Keating Dec. 2004, last updated Mar. 2005


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