The Learned Dog Class 3: The emotional context for learning...

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Transcript of The Learned Dog Class 3: The emotional context for learning...

The Learned Dog

Class 3: The emotional context for learning...

Agenda for the night...

• Questions

• Next week...

• The big ideas from Animals in Translation

• An ethological perspective on emotions

• The neurobiology of emotions

Next week: philosophy, single-event learning and the neural basis for learning

• Reading: Schwartz, chapters 1-2

• The philosophical basis for behavior theory

• The low-level neural basis for learning

• Single event learning as a case study

• A little more on the role of the amygdala

• A report from Carolyn on Chicken Camp

The super big idea of the evening (course)...

The super big idea of the evening (course)...TG: animals use emotion to predict the future...

The super big idea of the evening (course)...TG: animals use emotion to predict the future...BB: animals use learning to control the future...

Animals in Translation

A comment...

• What I like about the book...

• Takes an ethological view on emotion

• Relies heavily on the work of Jaak Panksepp, but presents it in an accessible form.

• Her opinions are nothing if not provocative

• What I don’t like about the book

• She often asserts things as if they were facts as opposed to her opinion

• I often disagree with her comments on dogs & dog training

Important ideas from Chapter 2.

• Animals focus on details, and often different details than humans

• Need to understand the sensory and perceptual mechanisms and biases, e.g. to what are they biased to attend.

• Disagree that animals don’t have a focus of attention, e,g., can’t filter out extraneous input.

• The three brain view: lizard, paleomammalian & neomammalian is useful at some level though probably wrong in many of the details.

Important ideas from Chapter 3

• Dangers of breeding for physical conformation vs. behavioral conformation

• 4 primal emotions & 4 social emotions (Panksepp)

• SEEKING system

• Emphasis on the importance of novelty. I disagree with her interpretation of novelty always being good.

• Confirmation bias

• Play

Important ideas from Chapter 4

• The distinction between Predatory Rage and Affective Rage

• I am not sure I buy all of her distinctions with respect to “affective aggression”, could all be lumped into fear-based reactivity. But maybe the distinctions are useful?

• I find her discussion of aggression and dogs to be a mixed bag, and there are probably better sources for advice: McConnell, for example.

Important ideas from Chapter 5

• Distinction between anxiety and fear??

• Using emotions to predict the future & the adaptive value of fear

• How animals learn what is scary: innate, prepared stimuli & observational learning, experience

• Fast fear, slow fear and weird fear

• Hypersensitivity & generalizing out to similar things in the same sensory category.

Emotions

How LeDoux defines emotion

• ‘Emotion defined as the process by which the brain determines or computes the value of a stimulus’

• As a consequence of this evaluation...

• ‘Emotional reactions occur. The overt bodily responses and associated changes in internal body physiology are the advance guard of emotional responsivity.’

• ‘Subsequently (at least in humans) a feeling emerges’

• ‘Given that we are in an emotionally arousing situation, we often take action. That is, we do things to cope with or capitalize on the event that is causing us to be emotionally aroused.”

LeDoux, J. (2002). Synaptic Self: How our Brains Become Who We Are. New York, NY, Penguin Books.

A key point here...

• Because the subjective experience of ‘feeling’ is difficult to measure in humans and we don’t know how to do it with animals yet, discussion of emotion in animals tends to focus on...

• Observable behavior (freeze, threat, affiliative, ...)

• The neural processing, hormonal response, learning and memory that seems correlated with the observable behavior

• With the assumption that there is an adaptive value to these mechanisms

Damasio & Descarte’s Error

• Emotion & cognition are inextricably linked.

• One theory...

• Certain types of emotion are ‘pre-cognitive’

• One effect of these emotional responses is to “speed up and improve decision-making by prebiasing other, computationally intensive cognitive systems, preventing them from considering particularly bad courses of action”

Cardinal, R. N., J. A. Parkinson, et al. (2002). "Emotion and Motivation: the role of amygdala, ventral striatum and prefrontal cortex." Neuroscience and Biobehavioral Revews 26: 321-352.

The major emotional systems in animals?

• Seeking (curiosity, anticipation)

• Fear

• Rage (affective & predatory)

• Panic (social bonding)

• Special purpose

• Lust

• Maternal Care

• Play

Panksepp, J. (1998). The Foundations of Human and Animal Emotions. New York, NY, Oxford University Press.

Emotions & what dogs do...

• The Volhard temperament model...

• Predatory

• Seeking, Play & Predatory Rage

• Social

• Seeking, Play & Social Bonding

• Threat (fight or flee)

• Affective Rage, Fear

The SEEKING system

Quick review of misbehavior

Desired

Actual

The common pattern of misbehavior

• The startling thing about misbehavior is the degree to which the opportunity to perform species-specific “appetitive” or seeking behavior may hijack the system even to the extent that it interferes with ultimately satisfying the very drive that the behavior is presumably “intended” to facilitate.

• Performance of the behavior is its own reward: the means become the end and the end is all but forgotten

• It was if the process of SEEKING was inherently self-rewarding, and indeed, more rewarding than the putative reward

• And it got stronger over time.

Rats would work in order to receive electrical stimulation to part of their brain...

• James Olds & Peter Milner first discovered that rats would work (press a lever, etc...) in order to receive electrical stimulation to a part of the hypothalmus (LH)

• The interpretation at the time...

• Invoked neural representation of a specific reward...

• e.g. “as good as eating the cookie”

• Exploratory behavior was secondary despite the fact that the observed behavior & affect was more akin to search/exploratory behavior than consummatory...

Panksepp’s reinterpretation of the findings...

• Panksepp took what everyone observed, but discounted, as the primary lesson, in fact, to be drawn from self-stimulation...

• The subjective feeling was one of “intense interest, engaged curiousity, and eager anticipation”

• The observable behavior(s) were those associated with active exploration of the environment. Indeed, cells in the LH fired when engaged in appetitive motor patterns, and stopped when in a position to handle or consume the object of interest.

• Species-specific appetitive behaviors

• His conclusion: it was the seeking not the finding that was rewarding...

The seeking system is invoked by...

• Regulatory imbalances

• External Stimuli

• Cues associated with incentives

Self-reinforcing behaviors???

• Things dogs do that may have roots in predatory (appetitive) motor patterns

• Tugging

• Chasing, Eye-stalk, Pounce

• Shaking & Ripping, Chewing

• Digging

• Retrieving

• Pulling

This phenomena can be our friend...

SEEKING System in Kittens...

• Leyhausen observed that kittens performed & perfected predatory motor patterns, e.g., pounce, on their litter-mates long before they were put to the test with real prey

• He hypothesized that appetitive behaviors were likely to be self-motivating & self-rewarding so that the animal would

• be motivated to practice, and perfect, behavior in a non-functional & safe context, e.g., play.

• still perform the behavior in the face of the fact that behaviors early in the predatory sequence fail more often than they succeed even in a mature predator.

Lorenz, K. and P. Leyahusen (1973). Motivation of Human and Animal Behavior: An Ethological View. New York, NY, Van Nostrand Reinhold Co.

Fear

How do we know an animal is in an emotional state we call fear?

• From Boissy:

• Observable behavior

• Freeze & tonic immobility (playing dead)

• Active Defense (threat or attack)

• Active avoidance (flight, hiding, escape)

• Other physical manifestations

• Neuroendocrine changes that seem correlated with above...

Boissy, A. (1998). Fear and Fearfulness in Determining Behavior. Genetics and the Behavior of Domestic Animals. T. Grandin. San Diego, Academic Press: 357.

Why the animal might respond to a given stimuli with behaviors we label as being associated with fear?

• From Boissy, again...

• ‘dangers the animal has learned to avoid’

• ‘stimuli that evoke an unlearned response’

• ‘novel stimuli’

• ‘physical characteristics ... [such as] fast-moving stimuli often provoke greater fear’

• ‘stimuli which arise from conspecifics, such as alarm calls’

Boissy, A. (1998). Fear and Fearfulness in Determining Behavior. Genetics and the Behavior of Domestic Animals. T. Grandin. San Diego, Academic Press: 357.

Grandin suggests that emotions such as fear serve as predictions of the future...

Under the hood: The amygdala as the ring master of emotional responses...

The amygdala in three slides

Quick but sometimes wrong is better than slow and sometimes dead...

LeDoux, J. (1996). The Emotional Brain. New York, NY, Simon & Schuster.

The amygdala in three slides

clickers are ‘low road’ all the way

LeDoux, J. (2002). Synaptic Self: How our Brains Become Who We Are. New York, NY, Penguin Books.

The amygdala in three slides

The amygdala rules: it is the ring master of emotional response

LeDoux, J. (1996). The Emotional Brain. New York, NY, Simon & Schuster.

LeDoux, J. (2002). Synaptic Self: How our Brains Become Who We Are. New York, NY, Penguin Books.

Grandin’s view: animals use emotions to predict the future...

• The amygdala responds on the basis of a quick and dirt analysis of sensory input.

• Via neurotransmitters, hormones, attendant bodily responses, the slower but more cognitive parts of the brain (e.g., the neo-cortex) are alerted to the future as predicted by the amygdala.

• The neocortex either confirms the prediction, or attempts to put the brakes on the response already put into motion by the amygdala

• For a variety of reasons, animals such as dogs are very much at the mercy of their amygdalas

The fear circuit as a case study...

The Fear Circuit

• The amygdala gets early sensory data from the sensory thalmus & then later from sensory cortex & memory

• Amygdala relies on coarse features to identify significant sensory events and if found...

• begins to initiate response

• primes itself to respond to higher level input from SC

• may guide interpretation

LeDoux, J. (2002). Synaptic Self: How our Brains Become Who We Are. New York, NY, Penguin Books.

Early

Middle

Late

Later inputs to the amygdala

• Sensory Cortex: more highly processed sensory input

• MTL: multi-modal representations of events, memories of facts and experiences. (Hippocampus part of MTL)

• Prefrontal Cortex: Higher level control and interpretation

• All serve to refine the activity of the amygdala including trying to put the brakes on if necessary

LeDoux, J. (2002). Synaptic Self: How our Brains Become Who We Are. New York, NY, Penguin Books.

Ultimately the amygdala ‘mediates reactions and

actions’

LeDoux, J. (2002). Synaptic Self: How our Brains Become Who We Are. New York, NY, Penguin Books.

Feedback mechanisms

• Direct connections from the amygdala back to other parts of the brain.

• Initiates production of various hormones that affect the state of the body and the brain

• The body responses themselves provide feedback to the brain

• All three mechanisms may in turn help inform the cognitive machinery that the body is having an emotional experience

LeDoux, J. (2002). Synaptic Self: How our Brains Become Who We Are. New York, NY, Penguin Books.

The soup of neurotransmitters and

their pathways

The amygdala is one of the primary cooks of this soup

Panksepp, J. (1998). The Foundations of Human and Animal Emotions. New York, NY, Oxford University Press.

Dopamine

• McConnell: ‘is vital to your brain’s ability to focus your attention—its release causes all of your brain cells to cease firing for a microsecond and then prepares them to fire in anticipation of an important event—but it’s also a key player in feelings of reward and satisfaction.’

• LeDoux: ‘Some adhere to the classic hypothesis— that it is the basis for reward. Another view is that dopamine release is important for the initiation and maintenance of anticipatory behaviors in the presence of secondary incentive stimuli. Others argue that dopamine release notifies the forebrain that something novel or unexpected has occurred, but not that reward per se has occurred. Still others propose that dopamine is involved in the switching of attention and selection of action. These are not mutually exclusive views and in fact each appears to correctly characterize certain aspects of what dopamine contributes to motivation.’

McConnell, P. (2006). For the Love of a Dog: Understanding Emotion in You and Your Dog. New York, NY, Ballantine Books.

LeDoux, J. (2002). Synaptic Self: How our Brains Become Who We Are. New York, NY, Penguin Books.

The amygdala, dopamine and action...

• One consequence of the amygdala being activated is that dopamine cells in the VTA are activated. Some of these cells release dopamine into a part of the brain known as the Nucleus Accumbens.

• The has the effect of amplifying signals coming from the Amygdala and this in turn allows the Amygdala to strongly activate and direct motor activity, e.g., flee or attack

LeDoux, J. (2002). Synaptic Self: How our Brains Become Who We Are. New York, NY, Penguin Books.

Stress pathways...

• One consequence of amygdala activity is the release of cortisol and other hormones (norepinephrine, ...) that have wide-ranging effects on the body and brain.

• The Hippocampus responds to the higher level by inhibiting the production of more

• At moderate levels, cortisol has the effect of strenthening connections & memory in the amygdala and hippocampus

LeDoux, J. (2002). Synaptic Self: How our Brains Become Who We Are. New York, NY, Penguin Books.

Stress pathways...

• At prolonged high levels of stress, the level of cortisol rises to the point where it actually interferes with the functioning of the hippocampus.

• Ability to form explicit memories (i.e., memories about context) is weakened

• Even more insidious, high levels of generalized stress may strengthen ‘weakly conditioned fear responses’ that have nothing to do with the stress LeDoux, J. (2002). Synaptic Self: How our Brains

Become Who We Are. New York, NY, Penguin Books.

Looking ahead at the role of the amygdala in learning...

The Amygdala plays a central role in CC

• ‘The BLA is required for a CS to gain access to the current motivational or affective value of the specific US that it predicts’

• The CeA ‘receives or may encode direct S-R Pavlovian associations, thereby influencing specific CRs... as well as modulating arousal and attention through diffuse projections’

Cardinal, R. N., J. A. Parkinson, et al. (2002). "Emotion and Motivation: the role of amygdala, ventral striatum and prefrontal cortex." Neuroscience and Biobehavioral Revews 26: 321-352.

Context conditioning occurs in Basal

amygdala

Rhinal cortex and hippocampus provide amygdala with high level representations such as context

LeDoux, J. (2002). Synaptic Self: How our Brains Become Who We Are. New York, NY, Penguin Books.

Lion

Lion in cage

The Nucleus Accubens plays a central role in Operant conditioning

• It helps to modulate conditioned and unconditioned responses...

• ‘It is a key site mediating the ability of Pavlovian CSs to invigorate and direct behavior.’

• It ‘mediates aspects of preparatory behaviour, temporally distant from the goal of behaviour (as opposed to consummatory behaviour, temporally close to the goal).’

Cardinal, R. N., J. A. Parkinson, et al. (2002). "Emotion and Motivation: the role of amygdala, ventral striatum and prefrontal cortex." Neuroscience and Biobehavioral Revews 26: 321-352.

LeDoux, J. (2002). Synaptic Self: How our Brains Become Who We Are. New York, NY, Penguin Books.

Conditioned responses, i.e., memories in the amygdala, are difficult or impossible to extinguish

• Experiments have shown that fear conditioning becomes resistant to extinction when the prefrontal cortex is damaged...

• The implication is that extinguishing fear conditioning is more about the cognitive machinery learning that “its ok”, as opposed to the amygdala forgetting

• Maybe why a single bad incident can seemingly undo months of careful counter-conditioning and desensitization.

• Think about “flooding” in light of this finding and the previous ones about the implications of high levels of stress on memory formation.

Emotional habits, once learned don’t seem to require the amygdala...

• LeDoux: ‘once an emotional habit is learned, the brain systems involved in expressing it become simpler’

• ‘Characteristically, amygdala-dependent signs of emotional arousal... occur during the initial phase of avoidance learning but disappear as the avoidance response is learned. The accumbens likewise drops out once the response is learned; while it is needed to do learning, it is not necessary to perform well-learned responses.

• ‘... perhaps the accumbens... trains prefrontal cortical circuits, especially areas of the motor cortex, how to respond’

• Do many behaviors we train our dogs eventually become emotional habits and so do not require constant reinforcement once learned and transferred?

Summary