Audio stimuli processing

Guide to process stimuli for PROSPR experiment

Downloading audio files

1. Login into github

2. Type 'BergelsonLab' in the search box on the top

3. On the Bergelson lab page, you will see a section called "Respitories". Click on the PROSPR respository.

BergelsonLab page with repositories

1. Click on the 'stimuli.zip' file. This should redirect you to another page. Click the three dot icon and download the file. (for Macs: press Cmd + Shift + s to download).

1. Save the stimuli folder to the desktop.

Installing Praat

1. Go to this link: https://praat.en.softonic.com/mac and download Praat

2. Install Praat

3. Open Praat

   When you open praat, two windows will pop-up: The Praat object window and the Praat picture.

Praat windows when Praat is opened

Create acoustic files with different intensities

• Order of Process

1. Click on Praat tab in the toolbar

1. Click 'Open Praat script... '

   • A Finder Window will appear. Follow this path: Desktop > stimuli > audio > scripts. In the scripts folder, you see two files, 'Norm_intensity_duration_carrier' and 'Norm_intensity_duration_target_word.' These two files set the duration and intensity to a fixed value for a subcomponent of the audio files.

     • The norm_intensity_duration_carrier sets the duration and intensity of all the carrier frames (e.g., "Look at the") to the same value.

     • The norm_intensity_duration_target sets the duration and intensity of all the target words to the same value.

     • Open the norm_intensity_duration_carrier file. A script (or code) will appear.

     
2. Adjust the following lines of code:

   • desired_intensity

     • This sets the intensity in dB. You will change the desired intensity three times (see table).

   • dir$

     • This sets the input directory. Set the directory to the lowpass folder (path: desktop > stimuli > audio > carrier_frames > lowpass). See table

   • newdir$

     • This sets the output directory. Set the output folder to the appropriate scaled_intensity folder (see table).

3. Click Run.

4. Repeat steps 1-4 for norm_intensity_target_word files.

Table. Folder names and desired intensities

PoS folder name	desired intensity	input folder name	output folder name
carrier_frames	70	lowpass	scaled_intensity_70dB
carrier_frames	75	lowpass	scaled_intensity_75dB
carrier_frames	80	lowpass	scaled_intensity_80dB
target_words	55	target_words	scaled_intensity_55dB
target_words	60	target_words	scaled_intensity_60dB
target_words	65	target_words	scaled_intensity_65dB