Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Created: January 20, 2015
Last Modified: January 17, 2024 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC
Script Copyright © Millisecond Software, LLC
This script runs a Serial Probe Recognition Task, a memory task used for memory research with animal populations, e.g. Sands & Wright (1980).
Sands, S. F., & Wright, A. A. (1980). Serial probe recognition performance by a rhesus monkey and a human with 10- and 20-item lists. Journal of Experimental Psychology: Animal Behavior Processes, 6, 386–396.
The default set-up runs the procedure for people (no feedback markers are sent; positive auditory feedback for correct responses). To send feedback markers, please go to a) section Editable Values and set feedback durations and b) trial.feedback and follow further instructions.
35 minutes
Computer presents lists of 10 picture stimuli; each stimuli is presented for 1s with a 800ms interstimulus interval in the top half of the computer monitor. 1s after the last list stimulus is presented, a probe is presented in the lower part of the computer monitor. Participants have 2s to decide whether the probe was part of the list. Half the probes are negative (the probe was not part of the list); half the probes are positive (the probe was part of the list) with each probe position (1-10) being represented equally often.
1 Block of 140 trial sequences
• 70 positive probe trials (7 per each of the 10 probe positions)
• 70 negative probe trials
The order of negative and positive probes (and probe positions) are randomly determined.
The items presented in each list are randomly selected.
trial sequence
• trial.start_positiveprobe/negativeprobe: resets crucial variables before each list starts and selects current probeposition
• trial.stimpresentation_positiveprobe: presents the list of 10 stimuli (each pic is presented for 1000ms with an isi of 800ms)
• trial.start_positiveprobe/negativeprobe: 1000ms after the last list item: presents the probe and waits for response for max.2000ms
• trial.feedback: presents only positive audio feedback (4000hz sound) by default; to send feedback port information
-> go to trial.feedback and follow further instructions
in this script:
210 images of animals, flowers, vegetables, and fruits (collected from the internet)
- 140 of these get randomly selected to be the list stimuli
=> results in repeats of stimuli after 14 lists (of 10 items) have been presented
(each item is repeated 10 times)
=> to avoid any repeats use: 1400 (+ 70 for the negative probes) list pictures for 140 trial sequences
(or use shorter lists and/or fewer trials)
- 70 (default: parameters.nr_trials/2) of these 210 stims are randomly selected to be the negative probes (these are not used for the lists)
=> no repeats of negative probes
generic instructions provided by Millisecond Software.
To change, go to section Editable Instructions.
File Name: serialproberecognition_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 |
| propCorrect | Overall proportion correct (across positive and negative probe trials) positive probe trial: probe is part of set negative probe trial: probe is not part of set |
| propCorrectNegProbe | Overall proportion correct for negative probe trials |
| propCorrectPosProbe | Overall proportion correct for positive probe trials propCorrectProbe1- |
| propCorrectProbe10 | Proportion correct responses for positive probe trials separate for each probeposition |
File Name: serialproberecognition_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 |
| currentProbePosition | Stores the position of the probe in the set |
| probestim | Stores the itemnumber of the probestim |
| stimulusItem | The presented stimuli in order of trial presentation |
| response | The participant's response |
| correct | The correctness of the response (1 = correct; 0 = incorrect) |
| latency | The response latency (in ms) |
| currentProbePosition | Stores the position of the probe in the set |
| probestim | Stores the itemnumber of the probestim |
The procedure can be adjusted by setting the following parameters.
| Name | Description | Default |
|---|---|---|
| nrStims | Number of stimuli in a set by default this script calculates summary variables for up to 10 possible probe positions if this number is changed, go to list.probeposition and change possible probe positions | |
| nrTrials | Number of trials to run | |
| stimDuration | Presentation duration of each of the stimuli in ms | 1000ms |
| regularIsi | Interstimulus interval between stimuli presentation in ms | 800ms |
| lastIsi | Time between last stimulus and probe presentation in ms | 1000ms |
| probeDuration | Duration of probe trial in ms | 2000ms |
| getReadyDuration | Duration (in ms) of get-ready trial | 5000ms |
| iti | Intertrial interval in ms | 500ms |
| positiveFeedbackDuration | Duration of positive feedback in ms | 200ms |
| negativeFeedbackDuration | Duration of negative feedback in ms to send positive or negative feedback markers go to trial.feedback and follow instructions |