Affective
Neuroscience
by
Jaak Panksepp
Humans and other animals
 Much of behavioral control is
elaborated by unconscious brain
processes
 Both animals and humans have
similar affective feelings that guide
their behavior tendencies
 So, analysis of animal emotions
provide new insights in the functional
organization of all mammalian brains
The simplest ways to learn about
feelings:
 To study human affective experience
across individuals and cultures
 To study animal emotive behavior
 To analyze animal's and human’s
brain circuits from which feelings
arise (including brain stimulation and
self-stimulation)
Why animals are better then humans
for studying emotions?
 Animal’s behavior is more emotional
because it is less influenced by
neocortex
 More freedom for experiments
 Human’s descriptions are rather
interfere then help…
Emotion and language
Some reasons why human words lie to us about our inner
world:
 Language emerged evolutionally as an especially
effective way for encoding the relationships among
external, not internal (so, not emotional) events
 One can verbalize only conscious content
 Transcription of experience into verbal symbols distort
reality
 Our two hemispheres have different emotional and
cognitive perspectives, and left hemisphere (that
speaks to others) may be more adept in lying and less
emotional
Evolutionary aspects – truine brain conception
Reptilian brain:
•Basic motor plans
•Primitive emotions (seeking,
fear, aggression, sexuality)
Paleomammalian brain – LS:
•More sofisticated variants of
reptilian emotions and
appearance of social
emotions
Neomammalian brain –
Neocortex:
•Cognitive/relational
apprehension of the outside
world
Schematic representation in the human brain of the
major axes of visceral and somatic processing, with their
convergence in reptilian brain (basal ganglia)
_____________________________________________
Issues of emotion research
 What are the underlying brain
circuits, in anatomical,
neurochemical, and
neurophysiological terms
 How emotional feelings emerge from
neurodynamics of many interacting
brain systems
 What is emotional self
Historical aspects
Classical psychoanalysis:
our feeling and thoughts are everything,
our biology does not matter
(conceptually enriched, scientifically
impoverished)
Radical behaviorism:
our feeling and thoughts do not matter,
our behavior is a set of learned responses
Ways of
viewing
the role of
emotions
in
behavior
Basic premises
 Emotional abilities are instinctual
(hardwired)
 As much emotive systems mature and
interact with higher brain areas (and
between themselves?) where they undergo
both re-representation and refinement,
organisms learn to make effective
behavioral choices in order to effectively
survive and propagate
 Different emotional tendencies emerge at
different developmental states
Subjective emotional experiences
(feelings)
 Fundamental property of emotional command systems
 Not epiphenomena but important causal factor in
mental life
 Not immaterial but true product of specific types of
neural circuits interactions
 Govern unconditional behavioral outputs
 May directly mediate learning by coding behavioral
strategies for future use
 May indirectly mediate learning by interacting with
“self-representational” system in brain
 Instinctual, i.e. genetically ingrained evolutional
learning
The major premises of Affective
Neuroscience about feelings
 Emotional processes, including subjectively
experienced feelings, play a key role in animal
and human behavior
 Feeling not only sustain unconditioned behaviors
but also help to learn new ones
 Feelings provide simple value-coding
mechanisms related to “the self”
 Feelings arise from the interactions of various
emotional systems with the brain fundamental
substrates of “the self”
 When feelings continue at low level for extended
periods of time, they generate mood and
personality dimensions (tendency to be happy,
irritable, melancholic, etc)
Emotion and cognition
 Clear distinction between affective and cognitive
processes exists, at least in the low reaches
 Primary substrates of emotionality are subcortical
(able to generate feelings without cortex)
 Emotions are precognitively organized
 Emotions are far more rigid then cognition (though
exhibit plasticity – it is interesting to what extend?)
 Cortex was evolutionally built upon preexisting
subcortical structures (including emotive systems)
 One of important functions of sophisticated and
flexible cortical organization is to overtake rigidity
of emotional systems
 It is impossible to understand cortical functions
(ratio) with no understanding of emotional systens
 Neural interactions elaborate a variety of
distinct periconscious states that has little
intrinsic cognitive resolution except various
feelings of “goodness” or “badness”
 As a result of mental maturation, those
periconscious affective systems inform our
higher cognitive apparatus how world
events relate to our intrinsic needs
(gradually establishing our higher value
system)
Definition of emotional systems
1.
2.
3.
4.
5.
6.
7.
8.
Capable of elaboration of subjective feeling states
that are affectively valenced
Various sensory stimuli can unconditionally access
them
Can generate instinctual motor output
Can modulate sensory input
Can modulate cognitive activities
Can be modulated by cognitive input
Can sustain emotional response after precipitating
events have passed
Interaction of emotional systems with circuits for
self-presentation - affective consciousness???
Criteria for defining basic emotional
systems
1. Valence of feeling
2. Underlying neural system
3. Character peripheral and expressive
changes of the body
Basic emotional systems
More primitive:
1. SEEKING
2. RAGE
3. FEAR
4. PANIC
Also,
5. LUST
6. PLAY
7. CARE
Evolutionary aspects – truine brain conception
Reptilian brain:
•Basic motor plans
•Primitive emotions (seeking,
fear, aggression, sexuality)
Paleomammalian brain – LS:
•More sofisticated variants of
reptilian emotions and
appearance of social
emotions
Neomammalian brain –
Neocortex:
•Cognitive/relational
apprehension of the outside
world
Biological
unfolding
of
emotions
Variety of human emotions




Affective-cognitive interplay?
Intermixture of several emotions?
Social-labeling processing?
Or perhaps totally new emotional systems
as a result of human brain evolution???
It is likely that our more subtle feelings are
the result of mushrooming of the cortex,
but it is unlikely that they could exist
without subcortical structures provided “raw
feelings”
Primitive SELF-Consciousness
 Ineffable feeling of experiencing oneself as
an active agent in the perceived events of
the world
 As it emerged early in brain evolution, it
should be within brainstem
 Consists of reverberating neural networks
linked to basic body tone and gross axial
movement generators
 Rooted in low-level brain circuits that first
represented the body as intrinsic and
coherent whole
SELF
Interaction between body schema and
incoming stimuli (both external and
internal)
↓
New kinds of reafferent reverberations
↓
Internal state of affective awareness
SELF
 Has concrete neuroanatomical,
neurochemical, and neurophysiological
characteristics
 Richly connected to the rest of the brain,
both higher and lower areas, presumably
more richly than any other area of the brain
stem
 Should be multimodal, allowing for
rerepresentation at many levels of neuroaxis
and during different ontogenic stages
 Rooted first in ancient midbrain regions
where neural motor maps (body schema),
sensory maps (world schema), and
emotional maps (value schema) first
intermixed
SELF
 Became more and more sophisticated
in the course of both ontogeny and
phylogeny (due to reshaping of
original form and addition of new
layers of neural control, esp. higher
layers)
 Fully developed SELF-consciousness
is an hierarchical but recursive set of
neural processors
And where exactly???
Nobody knows…
Deep cerebellar nuclei?
(receive a great deal of sensory &
emotional information and control
body movements)
Centromedial zones of midbrain?
(deep layers of colliculi and
periaqueductal gray)
Elaboration of basic emotional processes
Why them?
Deeper layers of colliculi:
 Constitute a basic motor system of the body
 Interact with visual, auditory, vestibular,
somatosensory systems
 Interact with nearby PAG
PAG:
 Elaborates a visceral-type map of the body
 Elaborates all basic emotional systems except PLAY
 Elaborates pain
Thank you
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Affective Neuroscience by Jaak Panksepp