Color Shape Task
Background
The Color-Shape Task is a cognitive-behavioral measure of executive functioning and specifically addresses the 'set shifting' subcomponent of executive control. As its name suggests, the Color-Shape Task is a simple categorization task of shapes by their color or their shape. The Color-Shape Task was published by Akira Miyake and colleagues in 2004 and incorporates elements from the Wisconsin Card Sort Task and the Random-Task Cuing Paradigm that provides explicit task cues to participants, eliminating guessing and the need to keep track of previously performed tasks. An analog children's version of the Color-Shape Task is the Dimensional Change Card Sort(DCCS).
The Color-Shape Task presents participants with one of two shapes (a circle or a triangle), in one of two colors (red or green). A cue (e.g. the letter 'S' or 'C' or the word 'Shape' vs. 'Color') precedes each shape, signaling which categorization task (shape vs. color) should be performed on the oncoming stimulus. The original design by Miyake et al (2004) included several manipulations such as testing performance in a blocked (categorization task is the same for all trials in a block) vs. mixed design (both categorization tasks run within the same block) as well as the nature of the cue (letter vs. word) and cue durations. The Color-Shape Task was further simplified (and significantly shortened) by Naomi Friedman and colleagues in 2008 who focused only on the mixed conditions (the actual set-shifting condition) with a fixed cue, presented at a fixed duration.
The Millisecond task library provides scripts for both experimental designs. The following 'Task Procedure' section describes the Color-Shape 'Shifttask' by Friedman et al (2008).
Task Procedure
Participants are shown red or green circles or triangles and have to either sort the stimuli by shape or by color as fast as they can. Participants are given cues (letters 'C' for color or 'S' for shape) before each stimulus appears that inform them which characteristic (color vs shape) to focus on. Each cue is presented by itself for 500ms. After 500ms the shape joins the cue. Both stay onscreen until a response is made using the keyboard keys 'A' or 'L'. A blank screen that is displayed for 600ms concludes each trial.
Participants work through a practice session of 48 trials. Error feedback is provided for 1000ms. Participants have to respond correctly to 85% of these trials to move on to the test session. After 5 failed practice sessions, the task prematurely terminates. The test session consists of 4 blocks of 48 trials each. Half the trials in each block are 'shift' trials (participants must shift from one categorization task to the other) and half are repeat trials (participants perform the same categorization task as during the previous trial); order is selected randomly (the actual number of color and shape tasks will therefore vary between participants). Performance feedback is provided after each block.
What it Measures
The Color-Shape Test is a cognitive-behavioral test of executive control, particularly set-shifting abilities.
Psychological domains
- Executive Control: Collection of "top-down" mental processes used to manage and regulate thoughts and actions
- Cognitive Flexibility: Shift to a new rule when the previous rule no longer applies
- Working Memory: storing and selecting the respective response button assignments for the different categorization tasks
- Sustained Attention: Maintaining focus over a repetitive series of trials without 'drifting'
Main Performance Metrics
- Switch Cost: the difference in response times to 'shift' and 'repeat' trials; measure of cognitive flexibility
Psychiatric Conditions
Color Shape Task performance has been found to be impaired in the following patient groups
- Traumatic Brain Injury (TBI)
- Parkinson’s Disease
- Attention Deficit Hyperactivity Disorder (ADHD)
- Autism Spectrum Disorder
- Schizophrenia
Test Variations
The Color Shape Shifting Task as developed by Miyake et al (2004).
The Color Shape Task as developed by Miyake et al (2004).
References
Search Google Scholar for peer-reviewed, published research using the Inquisit Color Shape Task.
Miyake, A., Emerson, M.J., Padilla, F., & Ahn, J.C. (2004). Inner speech as a retrieval aid for task goals: the effects of cue type and articulatory suppression in the random task cuing paradigm. Acta Psychologica, 115, 123–142.
Yerys, B. E., & Munakata, Y. (November 01, 2006). When Labels Hurt but Novelty Helps: Children's Perseveration and Flexibility in a Card-Sorting Task. Child Development, 77, 6, 1589-1607.