Transcript A Stage - Comparative Cognition Society

What Animals Never Operantly
Coordinate Actions with Sensory Input:
The Earliest Stages of Animal Behavior
Michael Lamport Commons
Patrice Marie Miller
Harvard Medical School
We describe developmental stages of
the least complex animals
 Several
reasons for doing this are
Understand the most basic task actions and how
they are controlled
Be more exact about how these basic units get
combined to form more complex tasks
Better understand evolution
Commons et al have proposed the Model
of Hierarchical Complexity (MHC)

This model can be used to determine behavioral stage
MHC orders tasks in terms of Hierarchical
complexity
A task action is defined as more hierarchically
complex when the higher order action
– is defined in terms of the actions at the next lower order
– organizes these lower-order actions
– in a non-arbitrary way
Explains stages of development
A Stage name and number corresponds to the order of
hierarchical complexity of a task it correctly
completes
This paper will focus mainly on Stage 1
 Stage
1 describes that organisms complete
tasks in which they are required to either act
or sense, but they do not complete tasks that
coordinate the two
First, we examine some Stage 1 tasks that
animals might complete
Second, we examine evidence for animals that
never progress further than Stage 1 in any area
Stage 0 – Calculatory
 Before
Stage 1, however, we describe stage 0
 At stage 0, both the detection of stimuli and the
production of responses are exact
There is no generalization
– All examples have to have been programmed
– Robots and computers respond this way
For computers, only written programmed learning is
possible
– The exception are neural networks, especially stacked
neural networks
 We
would assert that there are no animals that
function at this stage
Stage 1 – Sensory or Motor

The criterion for classifying action as Stage 1 is
The organism engages in a single action at a time
These actions are not coordinated with other actions
There are coordinations of stimuli

Both the detection of stimuli or the production of
responses are somewhat flexible
 But the relationship between them is not
For example, when water moves, mollusks open their
shells reflexively
If something touches their membrane, the shells close
There is very little variability in these responses
Many subtypes of zooplankton behavior is
confined to Stage 1
 Zooplankton are
floating or weakly swimming
They rely on water currents to move great distances
Microzooplankton are usually less than 200 mm
 Protozoa are a eukaryote subclass plankton
They are mobile and heterotrophic
– They use organic substrates to get carbon for growth and development
– Most protozoans are around 001–005 mm but up to 05
They are predators upon unicellular or filamentous algae,
bacteria, and microfungi
Possible Stage 1 behaviors seen in such
organisms
A Taxis is an organism’s directed physical action in
response to a specific stimulus
 A taxis can be a directional response or a non-directional
response (kinesis)

Phototaxis: flagellate protozoans of the genus Euglena move
towards a light source
Chemotaxis: Cells such as the free-living amebas or the
wandering cells of the Metazoa may detect the direction of a
potential food source through the chemicals that the food
sheds
Other kind of Taxis behaviors include: anemotaxis
(stimulation by wind), barotaxis (pressure), galvanotaxis
(electrical current), geotaxis (gravity), hydrotaxis (moisture),
phototaxis (light), rheotaxis (fluid flow), thermotaxis
(temperature changes) and thigmotaxis (physical contact)
Example 2: Phagocytosis
 Phagocytosis:
a way of obtaining
nutrients that involves an organism
completely surrounding a food particle
Amoebae: food object surrounded by
their pseudopods
In another protozoan, called a ciliate,
there is a specialized groove in the cell
where phagocytosis takes place
Example 3: Reflexes
 The
most complex stage 1 system are reflexes
 A reflex is a biologically-based system linking
stimulus to response
This may be mediated by a reflex arc only a few
neurons long
Here, the stimulus and the response are coordinated
– But the coordination is automatic
– It is simply due to the neural connection
 For
animals without neurons, we do not believe
there can be true reflexes
Some modification of a reflex is possible
 For
example, habituation of a reflex can occur
Habituation may be due simple process as neural
fatigue
Likewise with sensitization
 What
about stimulus generalization?
Stimulus generalization results from similarity of the
original eliciting stimulus to other stimuli
As a stimulus becomes less and less similar, it is less
likely to elicit the same response
For simple, physical stimuli the degree of similarity
can be measured quantitatively rather than in
hierarchical terms
So, behavior remains at stage 1
Is respondent conditioning also Stage 1?

One stimulus precedes closely before another stimulus
It can come to elicit the same or similar response

Pairing of the unconditioned and stimulus to be
conditioned is not a task that the animal must actively
solve
 This is so even though the stimuli must be salient
 The two stimuli are arbitrarily paired, either by an
accident of nature or by an experimenter
 This does not constitute an increase in the hierarchical
complexity of the task that must be solved
 The organism does not temporally or in some other way
organize actions in order to more adequately
accomplish this
Stage 2 – Circular Sensory- Motor

Even very primitive animals differentially respond to
stimuli, for example, rejecting non-food items
 They do not change their behavior based
on this environmental consequences
feedback following those responses

Every encounter with a food or a non-food object is
like a new encounter
Such animals may not operantly hunt for prey or forage

Some animals change their behavior in response to
consequences
 The consequences lead to them to Stage 2 behavior
in which they coordinate action with sensory input
Coordinating perception and action
or two or more actions

At Stage 2, animals coordinate operant action with
perception or they coordinate two or more actions
 Hunting behavior is controlled by consequences
(eg most predatory fish, insects) are performing at this
stage

Corrette (1990) observed prey capture in the praying
mantis
 They coordinated capture and strike movements
 Coordinating of multiple behaviors such as looking,
reaching and grasping require Stage 2 circular
sensory and motor action
Conclusion
 We
have described stage of actions by various
simple organisms
 The first two orders of hierarchical complexity
adequately described the tasks they accomplish
 Simple one-celled organisms that were not part
of groups of cells, functioned at stage 1
 Some multiple cell organisms that operantly
conditioned functioned at stage 2
 Some animals such as mammals probably
never function only at stage 1