Rat 50kHz calls reflect graded tickling-induced positive emotion

Justyna K Hinchcliffe, Michael Mendl*, Emma S J Robinson

*Corresponding author for this work

Research output: Contribution to journalArticle (Academic Journal)peer-review

22 Citations (Scopus)
109 Downloads (Pure)


Positive animal emotion (affect) is a key component of good animal welfare [1] and plays an important role in stress-coping and resilience [2]. Methods for reliably inducing and measuring positive affect are critical, but both have been limited in availability. In rats, one promising way of inducing positive affective states is by human-simulated rough and tumble play or ‘tickling’ [3,4]. However, in humans tickling induces both pleasure and displeasure, and neither an established non-verbal indicator of positive affect, the Duchenne smile, nor laughter detects this variation [5,6]. Rats also show individual differences in response to tickling [7], and this variation needs to be readily quantified if we are to ensure that tickling is only implemented where it generates positive affect. Here, we use a validated and objective measure of affective valence, the affective bias test [8], to show that 50 kHz ultrasonic vocalizations provide a quantifiable and graded measure of positive affect that accurately reflects the positive state induced by this human–rat interaction.
Original languageEnglish
Pages (from-to)R1034-R1035
Number of pages2
JournalCurrent Biology
Issue number18
Publication statusPublished - 21 Sept 2020


Dive into the research topics of 'Rat 50kHz calls reflect graded tickling-induced positive emotion'. Together they form a unique fingerprint.

Cite this