Dissociating Subjective Perception from Retinal Input

Visual stimuli falling on the retina automatically evoke neuronal responses in the central nervous system, but not all such responses lead to phenomenal awareness (Maunsell 1995). How are we to differentiate brain activity specific to consciousness from unconscious neuronal responses to visual stimuli Bistable percepts, in which a single pattern of retinal input gives rise to two alternating perceptual interpretations, provide a basis for such differentiation. Because changes in perception...

The Intermediate Level Theory of Consciousness

In earlier publications about the visual system of primates (Crick and Koch 1995), we suggested that the biological usefulness of visual consciousness in humans is to produce the best current interpretation of the visual scene in the light of past experience, either of ourselves or of our ancestors (embodied in our genes), and to make this interpretation directly available for a sufficient amount of time to the parts of the brain that plan possible voluntary motor outputs of one sort or...

Canonical Neurons

Since most grasping actions are executed under visual guidance, it is extremely interesting to elucidate the relationship between the features of 3D visual objects and the specific words of the motor vocabulary. In this logic the appearance of a graspable object in the visual space will immediately retrieve the appropriate ensemble of words. This process, in neuro-physiological terms, implies that the same neuron must be able not only to code motor acts but also to respond to the visual...

Self Consciousness Simulation and the Theory of Mind Concluding Remarks

In the present state of research on conscious agency attribution, there are still many questions to be answered, concerning in particular the cerebral mechanisms for agency attribution that are impaired in schizophrenic patients, and the difference between the impairments underlying, respectively, the delusion of influence (where the subject is not conscious of acting, but of being acted upon) and the delusion of control (where the subject believes that he can cause other people to act). One...

Broads Distinction between Emergent and Mechanically Explainable Properties

At the start of the twentieth century the question of whether life could be explained in purely mechanical terms was as hotly debated as the mind-body problem is today. Two factions opposed each other. Biological mechanists claimed that the properties characteristic of living organisms (metabolism, perception, goal-directed behavior, procreation, morphogenesis) could be explained mechanistically, in the way the behavior of a clock can be explained by the properties and the arrangement of its...

The Virtual Reality Metaphor of Consciousness

I have proposed (Revonsuo 1995, 1997) that we should take the concept of virtual reality as a metaphor for consciousness. To briefly summarize the ideas behind the VR metaphor, when the brain realizes the phenomenal level, it is actually creating the experience that I am directly present in a world outside my brain although the experience itself is brought about by neural systems buried inside the brain. The brain is essentially creating an the sense of presence in and the immersion in a...

Arbitrary Phenomenal Properties

This section is more technical than those above, and may be skipped by those not interested in philosophical details. One might try to give a general definition of an NCC of various states of consciousness, of which each of the above would be a special case. To do this, one would need a general way of thinking about arbitrary states of consciousness. Perhaps the best way is to think in terms of arbitrary phenomenal properties. For any distinctive kind of conscious experience, there will be a...