Emotions in non-human animals Flashcards
Questions to ask
–Do non-human animals have emotions?
–What are emotions anyway?
–Can they be described quantitatively as some form of physiological and/or behavioural response?
–How can we measure emotion in non-human animals?
–Is there an adaptive value to emotions?
–Influence on individuality? (diversity!)
Why should we bother about emotions in non-human animals?
–Implications for understanding how animals react to stress in wild and captive situations
–Therefore, how we approach issues of animal welfare.
–Ethical perspective
Some ‘emotional’ questions
What are emotions?
What are the behavioural & neurophysiological mechanisms behind emotions?
How do emotions arise in an individual; nature vs nurture?
–Do emotions develop through ontogeny? What is the role of experience?
–Are different emotions important at different stages of life history?
If emotions are not ubiquitous or the same across all animal life (and we might struggle to argue an anemone has emotions (at present!), then:
–When did emotions evolve? Which emotions evolved first?
–How did they evolve – what are the benefits* but what are the costs?
If emotions exist in non-human animals, what are they for?
–Is there an adaptive value to having ‘emotions’?
Emotions as part of individuality?
–Do emotions modify behaviour (-> intra-individual variation)?
–Do individuals differ in their ‘emotional range’? (-> inter-individual differences)?
–Do individuals differ in how emotions modify behaviour (different ‘thresholds’) (-> inter-individual differences)?
So, similar to ‘Personality’, can we think about emotion in non-human animals in an objective, scientifically rigorous manner?
–Can we define measure emotions?
–Can we measure emotions?
–Can we apply the behavioural ecological approach to understand adaptive value?
How to start?
*Well, defining terms is always a good start , but (like personality), this might not be so straightforward!!
*Important, because how we define something establishes what we are looking for
What is emotion
Conscious states causing affective (subjective). cognitive,
behavioural, expressive and physiological changes. Panksepp (2005a)
Multifaceted states with physiological, behavioural,
cognat.ve and subjective components.
Harding. Paul & Mendl (2004)
Orchestrated response to significant event across multiple
systems simultaneously: perceptual, cognitive, motivation,
expressive, bodily and experiential.
Barrett et al. (2007)
Temporary state brought about by biologically relevant
external stimuli. marked by specific changes in organism’s
body and mind (behavioural, physiological, cognitive)
which potentiate behaviour appropriate to environmental challenge.
de Waal (2011)
Intense. short-lived affective reaction to specific event or
stimulus.
Briefer (2012)
Class of behaviours expressing internal, functional and
adaptive states.
Anderson & Adolphs (2014)
Subjective experience resulting In specific response
LeDoux. Phelps & Alberim (2016)
Multicomponent response (subjective, physiological, neural,
cognitive) to stimulus or event.
Always valanced. might be intense/mild, long-lasting/brief.
Paul & Mendl (2018)
Key terms of emotions in non-human animals
Affective State
The position of an animal in ‘affective space’ , triggered by
environmental events and characterised by the axes arousal
and valance
(Panksepp, 2005a; Mendl et 2010).
Arousal
Intensity of a state, level of ‘activation’
(Mendl et al, 2009).
Core affect*
Emotionally charged states which influence reflexes,
perception, cognition and behaviour
(Russell, 2003; Panksepp, 2005b).
Mood
Long-lasting background state reflecting past experience
(arising from short-term emotions) and the environment
(Briefer, 2018).
Negative experience
Compromised physiological state, associated with
discomforts, pain and fear
(Panksepp, 2005b; Mellor, 2016).
Positive experience
Pleasure, good well-being and satisfaction
(Boissy et al., 2007)
Valance
Opposite states (joy/anger. happines/sadness). Core to
separating emotional feelings from sensations or perceptions
(Paul & Mendl, 2018)
*Affect defined as : the experience of feeling the underlying emotional state
Relative consensus is that emotions are short- lived states whereas mood is long-term
(see crossed arrow diagram in notes)
What is the evolutionary history of emotions?
emotions and the brain
*Emotions are mediated by the limbic system, which includes the hypothalamus.
*Limbic system: complex set of interconnected brain areas that integrate information about sensory stimuli, memories, and cognitive plans to produce emotional learning & emotional experience.
Common ancestors of reptiles and mammals (Synapsids; late Paleozoic and early Mesozoic) had a well-developed limbic system.
Birds evolved separately but around the same time as the mammals (c. 150mya), have a well-developed limbic system (different structure, but similar function)
Plutchik’s model: primary and mixed emotions
see diagram in notes
8 primary emotions,
which can be combined to form ‘Mixed’ emotions
adjacent emotions combine, also more widely separated emotions may combine e.g fear + anticipation = anxiety.
Primary Emotions:
- Basic, inborn, generalised, rapid, reflex-like
- Involve the amygdala (or similar neural circuit)
Secondary Emotions:
- Experience / evaluate / reflect
- Allows individual to make connections between feelings & action
- More complex - Involves higher brain centres in cerebral cortex - may be limited to animals with higher cognitive development
Which animals are capable of emotions
- Must have at least a central nervous system (Bekoff, 2002)
- Only need a rudimentary equivalent of the limbic system?
- However porifera and cnidaria show aversion to harm
- They have no centralised nervous system but do possess nerves throughout their bodies
Quantitative measurements of emotion
*Physiological
*Behavioural
*Cognitive
e.g. Mouse study: 3 lines = reward, 1 line = punishment when shown 2 lines mice had to make a decision from an ambiguous stimulus (unclear outcome) optimist will try and pessimist will avoid it.
Physiological measurements of emotions:
Endocrine responses
autonomic indicators
brain activity
+issues
Endocrine responses
*reflect change in internal state,
*e.g. cortisol (stress reaction, negative valence)
*Oxytocin (positive valence)
*measured in plasma, saliva, urine, faecal samples – issues though
*Other influences on endocrine responses though
Issues:
collecting samples can cause stress in itself usually causing fight or flight response releasing cortisol that could skew results
Captive animals can be trained to stay still and relaxed whilst samples are taken (seal left) although it is still not truly certain they are in a relaxed state
Autonomic indicators
- e.g. HR (e.g. Briefer 2018, landannde et al 2018)
- Increased HR == high arousal, stress states
- but is this really indicative of emotional state?
Brain activity
*functional magnetic resonance imaging (fMRI)
*Not much use in the field though!!
* e.g. dog being shown objects or listening to nonsense words said by their owner (frabjous)
Issues with physiological measurements of emotions:
–what do these measures actually indicate?
–Short term vs. long term responses/state (emotion vs mood??)
–Composite measures
Behaviour measurements of emotions
Non-invasive: ethical, larger sample sizes, more frequent data, practicable (esp. in wild studies)
e.g. Vocalisations indicate changes in emotive state in sheep and goats
*High arousal => longer/louder/higher/harsher/faster rate
*But exceptions - context/situational specificity
*+ve vs -ve valence of vocals – difficult to establish
– this also may not be the case in all species (Briefer 2012)
Quantitative measurements of emotions
Rat tickling experiment!! Bombail et al. (2019)
–Rats learn to associate an odour with the positive experience being tickled.
–Compared to controls, 50 kHz ultrasonic vocalisations of tickled rats increased when exposed to the odour they had previously experienced when tickled.
(See What Happens When You Tickle a Rat | National Geographic video YT)
Using facial expressions to quantify emotions
e.g. study of wolf facial expressions
by Elena Hobkirk MRes & Twiss
Can be used to classify +ve / -ve valence
Mammalian facial muscle architecture is similar between all species.
Facial action coding systems have been designed for different species to identify specific features and how they might change to give fine detail information on how expression changes in different contexts
BUT: Non-mammalian species have different facial arrangements and manouverability -requiring different analysis methods
Cognitive measurements of emotion
Cognitive processes generate emotional states that induce attentional, memory & judgement biases
-> measure of valence? (Panskepp 2011)
Optimist will investigate ambiguous symbol whereas pessimistic individual will avoid it
