Aim: The overarching aim is to understand the neural and neuroendocrine basis of social behaviour. The outcomes will have significant implications for our basic understanding of how positive emotional state impacts on the brain and physical health.
Juvenile social play behaviour is associated with positive welfare and positive emotional experience (Held & Špinka, 2011). The relationship between play, positive emotions and welfare is complex but adverse conditions (associated with poor welfare) supress play behaviour. Over 20 years ago a rat tickling model was developed to mimic rat social play behaviour by neuroscientist Jaak Panksepp (LaFollette et al., 2017; https://www.youtube.com/watch?v=d-84UJpYFRM). In this model the human hand is used to provide the tactile stimulation experienced during rat social play. The tickling procedure replicates the behavioural phenotype (more 50 kHz ultrasonic vocalisations (USVs) and more ‘hand-following’ in tickled vs. control rats).
By using the tickling rat model to mimic social play this project will investigate how positive emotion is regulated. This is essential to understand from an animal welfare viewpoint but is also important in relation to understanding how positive emotional states can provide protection e.g. to physical health. The project will examine the role of the somatosensory social brain and reward circuits in eliciting positive emotion. Emphasis will also be placed on:
1) Understanding the role of oxytocin and vasopressin and neurotransmitters (dopamine and serotonin) in regulating social play behaviour and/or responses to tickling.
2) Understanding the effects of early life experience on social play behaviour and/or responses to tickling: Variation in maternal care is known to affect later (post-weaning) levels of social play (Parent and Meaney, 2008). We will study how variation in maternal behaviour affects brain and behaviour responses to tickling, thus exploring mechanisms that underlie modulation by early life experience.
3) The effects of positive emotional state on the immune system and the microbiome: There is evidence that positive psychological state affects immune status and provides protection against disease (e.g. Rasmussen et al., 2009). We will use the rat tickling model combined with immune challenges to establish associations between positive emotional states in rats and central and peripheral immune markers and the diversity of the microbiome. This work will have relevance to human and animal health by linking positive emotional states with the physical outcomes independent of stress mechanisms.
Training: This project offers a wide range of training opportunities including experimental design, neurobiology, animal welfare, immunology and statistical analysis of a range of types of data. This studentship will train the student in skills including: neuroanatomy, neuroscience, physiology and animal behaviour. The student will take the lead role in data collection, interpretation and drafting manuscripts for publication. The student will be encouraged to engage with other scientists in the respective institutes to foster their own collaborations and attend and present their findings at UK and international conferences.
LaFollette, M.R., O’Haire, M.E., Cloutier, S., Blankenberger, W.B. and Gaskill, B.N. (2017) Rat tickling: A systematic review of applications, outcomes, and moderators. PloS one, 12(4), p.e0175320.
Parent, C., Meaney, M. (2008). The influence of natural variations in maternal care on play fighting in the rat. Developmental psychobiology 50:767–76.
Rasmussen, H.N., Scheier, M.F. and Greenhouse, J.B. (2009). Optimism and physical health: A meta-analytic review. Annals of behavioral medicine, 37(3):239.