Mood ring

A mood ring is a finger ring that contains a thermochromic element, or "mood stone", that changes colors based on the temperature of the finger of the wearer. Finger temperature, as long as the ambient temperature is relatively constant, is significantly determined by peripheral blood flow, which is modulated by the autonomic nervous system.^{[citation needed]} A mood ring contains liquid crystals that change color depending on the temperature.^[1]

^ Marechal, Catherine; et al. (2019). "Survey on AI-Based Multimodal Methods for Emotion Detection". In Kołodziej, Joanna; González-Vélez, Horacio (eds.). High-Performance Modelling and Simulation for Big Data Applications. Springer. p. 308. ISBN 978-3-030-16272-6.

[marechal-1] Marechal, Catherine; et al. (2019). "Survey on AI-Based Multimodal Methods for Emotion Detection". In Kołodziej, Joanna; González-Vélez, Horacio (eds.). High-Performance Modelling and Simulation for Big Data Applications. Springer. p. 308. ISBN 978-3-030-16272-6.

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