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- Machine Consciousness - Is intentionality a precondition of self awareness

Tino Schmidt† & Hagen Lehmann ‡‡ University of Bath, Artificial models of natural Intelligence

† Technische Universität Dresden, Institut für Allgemeine Psychologie

Models in neuropsychology are usually too complicated or too “abstract” to be useful for an integration into artificial cognitive systems. The main problem with these models is the lack of exact information about the time distribution mechanism between the different cognitive components. This is one reason why it is difficult to implement such models into programs. Examples for some of the most influencial cognitive models are Shallice (1988), Rosenthal (1997) and Wolpert (1995). Wolpert (1995) describes how actions are initiated and controlled by the human brain. But he gives, like in most of the other models, no further information about the distribution of time between actions and can therefore be called static model.Based on this “static” model we will integrate results from neurological research in order to create a model which includes both, the components of cognitive actions and the time distribution. We therefore refer to our model as “dynamic”.These dynamic enables binding between present and past state of the system. This kind of system information enables memory and the differentiation of new information. This is basic process of consciousness (Pasemann 1996, Port 1996) and describes the phenomenon of psychological representation.We differentiate between three levels of consciousness with different complexity: 1. Phenomenological consciousness 2. Intentionality3. Self awarenessSince human cognitive abilities evolved to be adaptive in dynamic environments and cognitive processes are dynamic by themselves we hope our model will help us to understand these processes better and with this understanding to create artificial cognitive systems.

INTRODUCTION

NEUROPHYSIOLOGICAL BACKGROUND

DYNAMIC MODEL

STATIC MODEL

REFERENCES

Wolpert’s model describes forward internal models of motor action. This kind of model predicts the consequences of actions and can be used to overcome time delays associated withfeedback control (Wolpert 1995).It is suggested, that impairments of the components of this model might underlie a broad variety of neuropsychiatric symptoms, like the anarchichand syndrome, phantom limb pain and delusions of control (Blakesmore et al 2002). Our model is based on this assumptions as we will show in the neuro -physiological background.

Figure 1: Forward internal model of motor action described by Blakesmore et al 2002: The actual state of the system is not directly available to the central nervous system. Instead, an estimated actual state of the system is inferred on the basis of the stream of motor commands, predictions based on the motor commands and sensory feedback.

Figure 2:Integration into the model: Lesion at position A leads to ataxia. Lesions at position B leads to anarchic hand syndrom

Intentionality can be described as based in the dynamic construction in the limbic system of directed motor patterns, that are delivered through the amygdala and septum into the lateral and medial forebrain bundles to the subthalamus and hypothalamus, then into the autonomic, and neuroendocrine effector systems.

Functions of intentionality are disturbed in the case of ataxia and the anarchic hand syndrome:

Ataxia is the failure of muscle control in arms and legs, resulting in a lack of balance and coordination. This is due to injuries in the cerebellum.Anarchic Hand Syndrome is characterized by uncontrolled behavior or the feeling of strangeness of one extremity, most commonly the left hand and an intermanual conflict. (Kritikos, Breen & Mattingley 2005)

- Blakesmore Wolpert & Frith (2002) Abnormalities in the awareness of action. Trends in Cognitive Sciences, 6 (6), p. 237-242. - Frith U., Morton J. & Leslie A.M. (1991). The cognitive basis of a biological disorder:

autism. Trends Neuroscience., 14(10), p. 433-8.- Kritikos A., Breen N. & Mattingley J.B. (2005). Anarchic hand syndrome: bimanual

coordination and sensitivity to irrelevant information in unimanual reaches. Cognitive Brain Research, 24(3), p. 634-47.Pasemann, F. (1996), Repräsentation ohne Repräsentation: Überlegungen zu einer Neurodynamik modularer kognitiver Systeme. In: G. Rusch, S.J. Schmidt & O. Breidbach (Hg.), Interne Repräsentationen, Frankfurt am Main.- Port, R.F. & van Gelder, T. (1996), Mind as Motion: Explorations in the Dynamics of Cognition, Cambridge. - Riddoch M.J. & Humphreys G.W. (2003). Visual agnosia. Neurologic Clinics of North America, 21, p. 501-520. - Rosenthal, D.M. (1997), A theory of consciousness. In: Ned Block, Flanagan & Güzeldere

(Hg.), The Nature of Consciousness, Cambridge. - Qiu F.T. & von der Heydt R. (2005). Figure and ground in the visual cortex: V2 combines stereoscopic cues with gestalt rules. Neuron, 47(1), p. 155-66- Shallice, T. (1988), Information-processing models of consciousness: possibilities and

problems. In: A. Marcel & E. Bisiach (Hg.), Consciousness in Contemporary Science, Oxford. 

-Wolpert, D.M. et al. (1995) An internal model for sensorimotor integration. Science 269, 1880–1882

      TECHNISCHEUNIVERSITÄTDRESDEN

by courtesy of mr - vorarlberg

Desiredstate

Goal

Specification of movement

Affordances

Intentionality is the precondition of self awareness, because it enables the differentiation between effects caused by self or by others. This is the connection between the base of phenomenological conciousness and social behavior, based on agents with a theory of mind.

Attribution of inputs on neural states

Differentiation between effects caused by self or by others

recognition of action – causation chains

learning of principle

goal oriented behavior – inverse action planing

theory of mind

Figure 3:

Taxonomy between the complexity of 3 levels of consciousness and their functions. As references for this taxonomy we show the related neurophysiological disorders: 1. Phenomenological consciousness: Visual agnosia is classified as inability to recognize familiar objects or faces. In general patients are able to describe objects in their visual field in detail, but are unable to recognize them. Therefore the memory is not affected by this disorder (Riddoch & Humphreys 2003). 2. Intentionality: as shown before: Ataxia & Anarchic Hand Syndrome 3. Self awareness: Autism is classified as a disorder what manifests itself in abnormal social behavior, limited ability to communicate, and reduced interests (Frith, Morton & Leslie, 1999).

Based on this model, intentionality is a key function of humans and animals as they are continuously generating hypotheses about the external world, testing their hypotheses by acting upon the environment and perceiving sensory information about the consequences of their action.

Time

80 ms

120 ms

proto-activation (content all possible desired states)

Copy as

„desired state0ms“ desired state

Action 1 predictive state 1 Action 2 predictive state 2 Action 3 predictive state 3

. . . .

Action n predictive state n

„actual state80ms“

new actual state

external stim.

external stim.

if predict. state ≠ actual state action becomes conscious

loop to

action selection (by pattern matching, comparing the desired state

with the predicted states of all possible actions)

+

Conciousness: forwarddating of „desired state0ms“

as „desired state120ms“

Specificationof movement

0 ms

if predict. state = actual state, the present actual state will be backdated to 80 ms

The model describes the progress of activation of several activity – patterns, representing goals, sequences of single actions, recognition patterns etc., during initiation and monitoring a motoric action.In the state called “proto – activation”, all possibilities of these patterns are represented by the frequency – characteristics of these patterns. This enables the neuronal network as a emergent system to generate “own” desires by the reinforcement of the dominant frequencies, and to stay flexible when new affordances are arising from the environment.Action selection is done by pattern matching between the pattern in the network, representing the desired state and the most similar pattern of a predicted state of all possibilities to act in this situation. At the same time, there are a lot of external stimuli and changes in the environment. Therefore, the network should copy each of its own states and orders into another functional part of the system for 40-80 ms. This causes the problem of time delay in reaction or, when the action is initiated before, the problem of loosing control over its own actions. There is the dilemma between the necessity to react as quick as possible and to stay flexible.In this model we facilitate a mechanism of a feed-forward and a feedback-loop.

Green lines are representing feedback – loops that backdate the actual perceived states of the environment as perceived in present, even though this effect has already happened. But to get the feeling of control to an organism, some form of working memory is required, which includes the activation of the predicted state of an action.Blue lines are representing feed-forward – loops to initiate conscious control as a information filter when the regulation of the action fails. Therefore information is filtered, but all conscious events seems to be present.

The model describes the progress of activation of several activity – patterns, representing goals, sequences of single actions, recognition patterns etc., during initiation and monitoring a motor action.