Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com), Millisecond
Created: January 03, 2012
Last Modified: January 06, 2023 by K. Borchert (katjab@millisecond.com), Millisecond
Script Copyright © Millisecond Software, LLC
This script implements a variant of the dichotic listening task to study selective auditory attention. The implemented procedure uses digits.
Koch, I., Lawo, F., Fels, J. & Vorlaender, M. (2011). Switching in the Cocktail Party: Exploring Intentional Control of Auditory Selective Attention. Journal of Experimental Psychology: HPP, 37, 1140 - 1147
28 minutes
Participants listen to 2 digits (1-9, no 5) simultaneously played in the left and the right ear, one spoken by a female and the other by a male voice. In each trial a colored cue (here: @) signals which of the two genders presents the target digit. The task is to decide if the target digit is less than or greater than 5.
• 2 levels of auditory attention switch (switch vs. repeat) x 2 levels of congruence of digits (congruent vs. incongruent)
=> 4 experimental conditions
(1) Auditory Attention Switch: tested within
Switch: if participant had to pay attention to male (female) channel in previous trial, participant is asked to pay attention to female
(male) channel for the current trial
Repeat: pay attention to the same gender in the current trial
(2) Congruence: tested within
Congruent: both digits are less (greater) than 5
Incongruent: one digit is greater and one is less than 5
• Color Assignments counterbalanced by groupnumber
BLOCKS:
(1) Experimental: 4 blocks
• each block runs 1 starttrial + 144 experimental trials (36 per experimental condition)
(starttrial is excluded from analyses, it cannot be one of the 4 experimental conditions as it can neither switch nor repeat)
(2) Practice: short version of the Experimental condition: 1 starttrial + 24 experimental trials (no data recorded)
TRIAL COMBOS:
trial.switch_congruent, trial.switch_inconcruent, trial.repeat_congruent, trial.repeat_incongruent (trial.starttrial)-> trial.response
• present a large @ sign in green and yellow (default) that signal to pay attention to male or female voice (counterbalanced for color-gender assignment)
(by default there is a 800ms pretrialpause before the cue comes on, and the cue stays on for 500ms before the digits are spoken)
• determine gender to be attended according to experimental condition
• randomly assign gender to the left and right channel
• randomly select a digit for the left ear and depending on experimental condition, randomly select from the congruent or
incongruent options for the right ear (excluding same digits for congruent condition, e.g. you cannot have "2" spoken in the left and right ear)
• randomly select one of the three soundfiles for each ear depending on digit and assigned gender
• sum up reaction times of correct responses and calculate corresponding mean (DV), separately for each condition
These data are recorded in the summary data file.
• errorfeedback for 1000ms
!!!NOTE!!!: Koch et al (2011) not only excluded the reaction times of the starttrials and reaction times of incorrect trials but also excluded
reaction time of trials with reaction times that exceed 3STDs of the mean. This script simply excludes data from starttrials as well as
reaction times of incorrect trials.
•3 soundfiles per digit per gender (3 different voices) = 2 * 3 * 9 = 54 (minus 6 soundfiles for digit 5 that are included for
algorithm purposes only)
!!!NOTE!!!!: the script has the necessary set-up to support using 3 sounfiles per gender per digit, however, at this point only
one actual soundfile per gender per digit is included. To add the remaining soundfiles go to Stimuli item.digitsounds.
provided by Millisecond in the form on images- can be edited under section Editable Instructions
File Name: dichoticlistening_digits_summary*.iqdat
| Name | Description |
|---|---|
| inquisit.version | Inquisit version number |
| computer.platform | Device platform: win | mac |ios | android |
| startDate | Date the session was run |
| startTime | Time the session was run |
| subjectId | Participant ID |
| groupId | Group number |
| sessionId | Session number |
| elapsedTime | Session duration in ms |
| completed | 0 = Test was not completed 1 = Test was completed |
| propCorrectOverall | Overall proportion correct across the 4 experimental conditions |
| meanRTOverall | Mean correct response time (in ms) across the 4 experimental conditions |
| propCorrectSC | Proportion correct in condition sc (shift, congruent) |
| meanRTSC | Mean correct response time (in ms) in condition sc (shift, congruent) |
| propCorrectSIC | Proportion correct in condition sic (shift, incongruent) |
| meanRTSIC | Mean correct response time (in ms) in condition sic (shift, incongruent) |
| propCorrectRC | Proportion correct in condition rc (repeat, congruent) |
| meanRTRC | Mean correct response time (in ms) in condition rc (repeat, congruent) |
| propCorrectRIC | Proportion correct in condition ric (repeat, incongruent) |
| meanRTRIC | Mean correct response time (in ms) in condition sic (repeat, incongruent) |
File Name: dichoticlistening_digits_raw*.iqdat
| Name | Description |
|---|---|
| build | Inquisit version number |
| computer.platform | Device platform: win | mac |ios | android |
| date | Date the session was run |
| time | Time the session was run |
| subject | Participant ID |
| group | Group number |
| session | Session number |
| blockCode | Name of the current block |
| blockNum | Number of the current block |
| trialCode | Name of the current trial |
| trialNum | Number of the current trial |
| group | Group number |
| parameters.smallerkey/largerkey | The scancode for the "smaller"/"larger" keys |
| parameters.colorname1/colorname2 | Hold the NAME of the two colors |
| blockCount | Counts the experimental blocks run |
| expCondition | The experimental condition run 0 = starttrial 1 = switch-congruent (sc); 2 = switch-incongruent (sic) 3 = repeat-congruent (rc); 4 = repeat-incongruent (ric) |
| genderattention | 1 = pay attention to female voice 2 = pay attention to male voice |
| genderLeft/genderRight | The gender of the voice in the left/right ear, 1 = female; 2 = male |
| digitLeft/digitRight | The digits to play in each ear |
| leftIndex/rightIndex | The index number of the left/right soundfile to be played |
| response | The participant's response (e.g. scancode of response button) 16 = Q (left) 25 = P (right) |
| correct | The correctness of the response (1=correct; 0 = error) |
| latency | The response latency (in ms) |
The procedure can be adjusted by setting the following parameters.
| Name | Description | Default |
|---|---|---|
| largerkey | The scancode for the "smaller" (Q)/"larger" keys (P) | |
| color1/color2 | The colors associated with gender Assignment is counterbalanced by groupnumber | |
| colorname1/colorname2 | String variables that holds the NAME of the two colors if you change the colors and/or key scancodes, you need to make appropriate changes to item.intros |