Mr Peanut Test
Background
The Mr. Peanut Test (also referred to as Mr. Potato/Cucumber/Clown Test) is a cognitive-behavioral psychological measure of visuospatial working memory capacity (WMC), primarily in children (usually ages 6 to 11). Originally adapted by developmental psychologists (drawing from the cognitive theories of Robbie Case and Sergio Pascual-Leone) and formally outlined in studies like those by Sergio Morra in 1994, the test evaluates how well a child can mentally track, hold, and recall visual and spatial information over a short period.
The main character of the test is a cartoonish figure called 'Mr Peanut' who gets decorated with a variable number of dots (referred to as 'stickers') on various body parts such as the arms, legs, ears, mouth and nose etc (up to 14 potential locations). Participants must remember the locations (and potentially the color of the dots) for a later recall test.
The complexity of the test increases progressively; starting with remembering 1 or 2 locations and increasing to 5, 7, or more as the child successfully passes the trials. Researchers use the test to measure a child's spatial working memory, studying how visual memory capacity expands with age or how it correlates with academic performance, such as math fluency and spatial reasoning.
Millisecond's Mr Peanut test comes in two versions: the basic purple Mr Peanut test (all stickers are purple; measures recall of spatial locations only) as well as the advanced color version of the test (stickers come in different colors; measures recall of spatial locations and memory of colors). Depending on the script's setting the levels of N tested can increase progressively based on performance or the levels can be fixed and run in random order. By default, the test uses progressive testing.
Task Procedure
After learning about the clownish figure called 'Mr Peanut' who decorates himself with purple stickers (on 14 possible body part locations), participants work through three practice trials. Incorrect practice trials are repeated. The test starts at level N=1 showing one purple sticker located on a specific body part (e.g. the left leg) for 1 second (per sticker). After a delay of 1 second, participants must touch (via mouse click or finger touch) the location of the sticker to recreate the sticker placement (after touching the location, a purple sticker appears in the selected location). Recall is over by pressing a 'Done' button, so that participants can correct their sticker placements if needed. The order of the sticker placements is predetermined for the progressive testing mode.
If participants get at least one out of three attempts per level correct, they move up to the next level. Each new level increases the presentation time
by 1 second. If all 3 attempts per level fail, the test concludes. A total score is calculated based on the rules outlined by Morra (1994):
• for consecutive levels for which participant gets over 50% of the trials correct, they get 1 point
• for remaining levels, 1/3 point is added for each correct response per level.
The testing procedure of the colorful Mr Peanut version is similar, but the test presents stickers in various colors on Mr Peanut and asks participants to select the color of the sticker before placing them. The test tracks location placement and color selections. Performance is based on the correct placement and correct color selection.
What it Measures
The Mr Peanut Test is a cognitive-behavioral test of visuospatial working memory capacity
Psychological domains
- Spatial Short-Term Memory: Passive holding of spatial information in working memory
- Visuo-Spatial Working Memory: Passive holding of spatial information in working memory with keeping track of colors
Main Performance Metrics
- Highest Successful Level: The highest level of N reached
- Total Trials: The number of trials run
- Error Attempts: Tracks the number of errors made
- Total Score: Takes into account consistent correct performance and highest level reached; overall measure of visuo-spatial memory capacity
Psychiatric Conditions
While the Mr Peanut Test is largely used within healthy, neurotypical pediatric populations to establish baseline cognitive development milestones, researchers also use the test to evaluate several specific clinical and educational patient cohorts such as:
- Autism Spectrum Disorder (ASD)
- Attention-Deficit/Hyperactivity Disorder (ADHD)
Test Variations
The Mr. Peanut Test with location only as described in Morra (1994).
The Mr. Peanut Test with location and color as described in Morra (1994).
References
Search Google Scholar for peer-reviewed, published research using the Inquisit Mr Peanut Test.