Hello everybody,
I have a problem in the following issue: I generated some sounds and right now, because every person has a specific auditory threshold for each frequency in order to hear a sound, I want to write a script in Matlab for determine this threshold. does Psychtoolbox have this feature in order to estimate auditory threshold???
if you know about it or you know other toolbox in Matlab for estimating this threshold I really appreciate if you tell me about that I really stuck and need it a lot. (in this bellow you can see a picture which illustrate auditory threshold for each frequency for both ears (right and left ear) I want to simulate such this picture in matlab) Thanks in advance.
PTB can run an experiment to estimate an auditory threshold. But you will need to develop the code to run this. Estimating thresholds can be done using several different paradigms, broadly split into constant and adaptive methods. Constant just means you have 10 different sensory signals and repeat each for example 10 times, then draw a psychometric curve. An adaptive staircase starts at a high signal strength then reduces the signal value stepping down and up using a set of rules until the subject is performing at a chance level. My personal favourite book for students:
Kingdom, F.A.A. & Prins, N. (2016) Psychophysics: A Practical Introduction, 2nd edition. Academic Press: an imprint of Elsevier, London
The book has an accompanying toolbox, Palamedes, that works well alongside PTB. They have demos for several different staircase methods:
http://www.palamedestoolbox.org/index.html
There are also adaptive tools built-in to PTB, but for students Palamedes and the accompanying book provide a better learning experience.
Thanks a zillion for answering, and sorry for not getting back to you sooner.
but which function of Palamedes can I use for estimating auditory threshold??
There are lots of function after downloading palamedestoolbox and I don not know which one is useful for finding auditory threshold for both ears???
Auditory tresholds are no different from other thresholds, same methods used to measure them. It seems you’re not familiar with these methods. Read the book of Prins and Kingdom which will tell you about them, and the toolbox i believe
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As Dee mentions, a threshold can be taken for sight, hearing, touch, smell etc. The Palamedes functions calculate a value, they don’t run an experiment. You will need, for example, a simple staircase with the PAL_AMUD functions (AM = adaptive methods, UD = up-down), a demo is available with PAL_AMUD_Demo that demonstrates obtaining an arbitrary stimulus threshold:
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You will need to use PTB audio functions to generate the auditory stimulus, you can have a look at BasicSoundOutputDemo for example. Then use the Palamedes staircase function to provide the volume to the PTB audio output commands. There is no “ready-to-use” auditory threshold code available that I know of…
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I really appreciate for sharing your knowledge. Right know I am working with psychoacoustics toolbox and it has 3 approach (Staircase, MLP and PEST) for estimating threshold and it truly helped me.
https://dpg.unipd.it/en/mlp
again Thanks a lot
Sure, I am so interested in reading this book but I could not find it as a free book, It is so expensive and I cannot afford it, Could you please send its pdf if you have it??
https://www.elsevier.com/books/psychophysics/kingdom/978-0-12-407156-8
You could also consider psylab:
If you download from github, you’ll find a PDF manual in the documentation folder. Psylab has several procedures (often referred to as two alternative forced choice) which will do what you want. The code is designed to be easy for beginners to adapt.
Keep in mind, though, that you’ll need to calibrate the output of your computer system accurately in order for your estimates to have norm-validated references. To do this, you’ll need to follow the same procedures (e.g. 2 cc couple with Brüel & Kjær investigator) which you would for calibrating an audiometer. These use specialist equipment, which you’ll find in the audiology department of your university.
If you aren’t bothered about validating your output levels (e.g. because you are only interested in between group comparisons) you might be able to skip the calibrations. Doing so could create problems though. For example, if you want to publish your data, reviewers may want to see calibrated sound pressure levels. Also, if you plan to use high stimulus levels (e.g. anything above about 70 dB HL) you should be very careful with overall sound exposure levels.
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Thanks a lot for sharing such this useful data.