Yoni Test

Background

The Yoni task is a computerized neuropsychological assessment of an individual's Theory of Mind (ToM)—the ability to understand mental states, such as emotions and thoughts, based on facial expressions and gaze direction of others. The test is particularly valuable in neuropsychology because it minimizes the influence of other domains like language, long-term memory, and executive functioning.

Introduced by Simone G. Shamay-Tsoory and Judith Aharon-Peretz in 2007, the Yoni Test allows a unique distinction between measures of 'affective ToM' ("Yoni loves X") as opposed to 'cognitive ToM' ("Yoni thinks of X") measures. The authors present strong evidence that affective ToM processing is distinct from cognitive ToM and depends in part on separate anatomical substrates. For example, individuals diagnosed with psychopathy and those with orbitofrontal cortex lesions show impairments on the 'affective ToM' measures but not on the 'cognitive' ones (Shamay-Tsoory et al, 2010).

The Yoni Test uses static, cartoon-like pictures of a character named "Yoni" surrounded by faces and/or objects in the corners of the screen. The Test evaluates first-order (e.g. Yoni thinks of X) and second-order ("Yoni is thinking of the fruit that X wants") affective and cognitive mental state attributions. Additionally, physical control items ("Yoni is near to X") are included to ensure that any identified deficits are specific to social cognition rather than general visual processing or attention.

The original Yoni Test runs 98 trials divided into three phases:

1. Phase A: presents first-order cognitive (8), affective (8) and physical trials (8) in a mixed design.
2. Phase B: presents a mixture of first order "cognitive" and "affective" (4 trials each) trials and second order affective trials (24) in a mixed design. Object categories differ from Phases A/C.
3. Phase C: presents second order cognitive (24), affective (12) and physical trials (6) in a mixed design.

In 2022, Sara Isernia and colleagues published two validated shortened versions, the 48-item and 36-item Yoni Tests, used for quicker assessments in research and clinical practice. Their data supports that all three Yoni Tests have high reliability and good convergent validity with 'The Reading the Mind in the Eyes Test'.

Millisecond Software provides all three versions in the Millisecond library.

Task Procedure

The following procedural description applies to the 48-item Yoni Test but the general procedure is the same for all. The 48-item procedure presents a randomized but fixed sequence of trials. After a brief introduction to the test, participants work on 48 slides (cognitive: 21, affective: 21, physical: 6). Each cognitive ("Yoni is thinking of X") and affective ("Yoni loves X") slides presents Yoni in the center of the slide, with equal distance from 4 faces and/or objects in the four corners. For physical control trials ("Yoni is near X"), Yoni is printed next to one of the four faces/objects. The facial expressions as well as gaze directions of Yoni and/or the four faces vary. The ToM attributions are printed on top of the slide. Participants respond by clicking (or touching) the face/object that best fits the statement. To answer the questions correctly, participants have to take into account physical distance and gaze direction as well as facial expressions of Yoni and the four faces (in 2nd order trials).

There is no feedback given during the test.

What it Measures

The Yoni Test is a measure of cognitive and affective ToM

Psychological domains

• Theory of Mind: Ability to interpret mental states of others, independent of one's own
• Affective Theory of Mind: Ability to infer others' emotions or feelings (e.g., 'Yoni loves...').
• Cognitive Theory of Mind: Ability to infer others' thoughts, intentions, or beliefs (e.g., 'Yoni is thinking of...')
• Physical Reasoning: Ability to make visuoperceptual and physical inferences (e.g., 'Yoni is close to...')

Main Performance Metrics

• Accuracy: The overall proportion of correct mental state attributions, as the overall measure of ToM abilities
• Response Time (RT): A measurement of processing speed for social information
• Cognitive/Affective Accuracy Index: A measurement of balance between cognitive and affective components

Psychiatric Conditions

The following patient groups show impacted performance on the Yoni Test:

• Autism Spectrum Disorder (ASD)
• schizophrenia
• Psychopathy
• Parkinson's Disease
• Multiple Sclerosis (MS)
• Huntington's Disease
• Mild Cognitive Impairment

Test Variations

References

Search Google Scholar for peer-reviewed, published research using the Inquisit Yoni Test.

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Shamay-Tsoory, S.G. & Aharon-Peretz, J. (2007). Dissociable prefrontal networks for cognitive and affective theory of mind: A lesion study. Neuropsychologia, 45, 3054–3067.

Bodden, M. E., Mollenhauer, B., Trenkwalder, C., Cabanel, N., Eggert, K. M., Unger, M. M., Oertel, W. H., ... Kalbe, E. (August 01, 2010). Affective and cognitive theory of mind in patients with parkinson's disease. Parkinsonism and Related Disorders, 16, 7, 466-470.

Terrien, S., Stefaniak, N., Blondel, M., Mouras, H., Morvan, Y., & Besche-Richard, C. (March 30, 2014). Theory of mind and hypomanic traits in general population. Psychiatry Research, 215, 3, 694-699.

Takagishi, H., Koizumi, M., Fujii, T., Schug, J., Kameshima, S., & Yamagishi, T. (January 01, 2014). The role of cognitive and emotional perspective taking in economic decision making in the ultimatum game. Plos One, 9, 9.)

Isernia, S., Rossetto, F., Blasi, V., Massaro, D., Castelli, I., Ricci, C., Shamay-Tsoory, S., Marchetti, A., & Baglio, F. (2023). Measuring cognitive and affective Theory of Mind with the Italian Yoni task: normative data and short versions. Current Psychology (New Brunswick, N.J.), 42(27), 23519–23530. https://doi.org/10.1007/s12144-022-03457-5

Isernia, S., Rossetto, F., Shamay-Tsoory, S., Marchetti, A., & Baglio, F. (2023b). Standardization and normative data of the 48-item Yoni short version for the assessment of theory of mind in typical and atypical conditions. Frontiers in Aging Neuroscience, 14, 1048599. https://doi.org/10.3389/fnagi.2022.1048599