Modified Camel and Cactus Test - MCCT

Technical Manual

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com), Millisecond

Created: January 09, 2023

Last Modified: January 02, 2025 by K. Borchert (katjab@millisecond.com), Millisecond

Script Copyright © Millisecond Software, LLC

Background

This script implements Millisecond's computerized version of the Modified Camel and Cactus Test (mCCT) developed by Moore et al (2022) on behalf of the Genetic FTD Initiative (GENFI) as a short alternative to the original Camel and Cactus Test (CCT) by Bozeat et al (2000). The mCCT is a test of semantic memory independent of language.

References

Moore, K et al (2022). A modified Camel and Cactus Test detects presymptomatic semantic impairment in genetic frontotemporal dementia within the GENFI cohort. APPLIED NEUROPSYCHOLOGY: ADULT 2022, VOL. 29, NO. 1, 112–119 https://doi.org/10.1080/23279095.2020.1716357 complete paper and pencil test is published in the supplementay materials

Bozeat, S., Lambon Ralph, M. A., Patterson, K., Garrard, P., & Hodges, J. R. (2000). Non-verbal semantic impairment in semantic dementia. Neuropsychologia, 38(9), 1207–1215. doi:10.1016/S0028-3932(00)00034-8

Duration

5 minutes

Description

Participants see 1 target item on top of the screen and 4 comparison items on the bottom. They are asked to find the comparison item that goes best with the target item. In this script, participants can correct their responses until they press button 'Next'. There are 3 practice trials and a total of 32 (fixed) test trials.

Procedure

1. Practice: 3 trials
- 3 practice trials with feedback (by default feedback is presented for 5s)
- items are presented in fixed order

2. Test: 32 trials
- 33 test trials without feedback
- items are presented in fixed order

Stimuli

All items were taken from the supplementary document of Moore et al (2022).
Separate image files were prepared for each target and comparison items
and stored as 800x800px images.

Instructions

provided by Millisecond - can be edited in script 'mcct.iqjs' (instructions are language dependent)
Instructions were based on instructions in the paper and pencil version but adapted by
Millisecond for computer use.

Summary Data

File Name: mcct_summary*.iqdat

Data Fields

NameDescription
inquisit.version Inquisit version number
computer.platform Device platform: win | mac |ios | android
computer.touch 0 = device has no touchscreen capabilities; 1 = device has touchscreen capabilities
computer.hasKeyboard 0 = no external keyboard detected; 1 = external keyboard detected
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
mCCTScore Final number of correctly selected items
mCCT > 27 considered normal
mCCT = 27 considered borderline
mCCT < 27 considered abnormal
(see Moore et al, 2022, p.115)
meanCorrRT Mean submit response time (in ms) for correctly selected items

Raw Data

File Name: mcct_raw*.iqdat

Data Fields

NameDescription
build Inquisit version number
computer.platform Device platform: win | mac |ios | android
computer.touch 0 = device has no touchscreen capabilities; 1 = device has touchscreen capabilities
computer.hasKeyboard 0 = no external keyboard detected; 1 = external keyboard detected
date Date the session was run
time Time the session was run
subject Participant ID
group Group number
session Session number
blockcode The name the current block (built-in Inquisit variable)
blocknum The number of the current block (built-in Inquisit variable)
trialcode The name of the currently recorded trial (built-in Inquisit variable)
trialnum The number of the currently recorded trial (built-in Inquisit variable)
trialnum is a built-in Inquisit variable; it counts all trials run
even those that do not store data to the data file.
trialCounter Tracks the number of problems run
itemNumber The itemnumber of the currently presented problem
response The selected image/button of the current trial
values.rsp The number (1-4) of the currently selected image
1 = top, left; 2 = top, right
3 = bottom, left; 4 = bottom, right
correctRsp The image number of the current correct response
correct 1 = the selected response (rsp) is the same as the correctRsp
0 = otherwise
participants can change their selection until they press 'submit'
countCorrect The cumulative number of correct selections (established when participants press 'submit')
latency Response latency (in ms) of the current trial; measured from: onset of trial
rtSubmit The cumulative latency (in ms) until submit-button is pressed

Parameters

The procedure can be adjusted by setting the following parameters.

NameDescriptionDefault
Timing Parameters
practiceFeedbackDurationMS The duration (in ms) of the practice feedback trial5000