Giving reference to the kinds of phenomena that each type of consciousness theory can be used to explain, this essay outlines three types of consciousness that explain different areas of conscious functioning. Access consciousness, that involves accessing information from different kinds of mental processes; Monitoring consciousness which is a form of consciousness that allows us to reflect on our own activities and mental states and Self consciousness that involves a concept of self and its use in thinking and reflecting on oneself.

The essay goes on to discuss a further type of consciousness, phenomenal consciousness, which is an aspect of consciousness that involves the 'raw feel' or experience associated with consciousness and explains why this type of consciousness has been described as the 'hard problem' of this area. Block (1991, cited in Braisby 2002) refers to the kind of conscious experience that involves access to information from different kinds of mental processes, as access consciousness.Young and Block (1996, cited in Braisby 2002) propose that we are 'conscious in the sense of being access conscious whenever we think about a mental state, "report its content, and use it to guide action"' This notion can include thinking about feelings and memories. Conscious perception defined in terms of awareness of aspects of the environment, that integrates stored knowledge and sensory information can be seen as a kind of access consciousness. Acts of recognition and recall also involve access consciousness.

Verbal reporting provides evidence that there is some conscious access to processes used to process information and perform tasks and provides the foundation of techniques involving protocol analysis where participants report verbally whilst performing a task. The complexity of the relationship between consciousness and information processing can be illustrated by looking at visual neglect, a condition caused by brain damage. In this condition there appears to be a failure to attend or perceive certain aspects of the environment.For example, when asked to draw a clock face, people with unilateral neglect may leave out the left half, whilst others may squash all the numbers onto the right side, in both cases, they do not draw a complete face. A further condition explained by access consciousness, is blindsight in which those affected appear to experience a kind of blindness without actually being blind. Monitoring consciousness is the kind of consciousness we have that involves monitoring and reflecting on our own actions and mental states thus allowing us to take action as necessary and appropriate.

James Reason (1979, cited in Braisby, 2002) conducted a diary study in which he asked his participants to record an entry each time they made an error in their everyday tasks. Examples of such errors include unwrapping a sweet, putting the paper in the mouth and throwing the sweet away and stepping into the bath whilst still wearing socks. Normally, monitoring of these types of actions is taken for granted; it is only when things are done wrong that we realise that we have not been monitoring our actions closely enough.Reason suggests that complex sequences of actions require some highly automated processes, but at certain points in these sequences controlled processes are needed - maybe to choose between two competing automatic processes - in order for the sequence to be carried out successfully.

Failure of this conscious monitoring leads to errors. Failure of monitoring consciousness is illustrated in people with anosognosia, a condition in which a patient is unable to recognize and deal with his or her own disease or impairment.Damasio (1999, cited in Braisby 2002), describes a patient with complete left sided paralysis. Despite being unable to move her left hand and arm, she would say that it was healthy and unimpaired. Patients with this condition appear impaired in their conscious ability to monitor the behaviour of their bodies, but retain other aspects of consciousness. Self consciousness is a form of consciousness that involves a concept of 'self' and its use in thinking and reflecting on oneself.

It involves an awareness of the self in the past, the present and the anticipated future.It suggests a wide sense of awareness that encompasses an autobiographical sense of self. Some cases of amnesia illustrate this concept of self consciousness, where autobiographical memory is disrupted after sustaining head injuries. Damasio reports on a patient who experienced amnesia following a head injury.

After the accident, the patient awoke confused with no sense of who he was. Self consciousness can also be illustrated in people with asomatognosia, a condition where patients appear unable to recognize their own bodies.Damasio for example, describes a patient following a stroke who was unable to feel her body, so apparently lost her sense of being an embodied self. Phenomenal consciousness goes beyond information processing or knowledge that might be gained whilst conscious and involves the 'raw feelings' or experience of consciousness.

It is in essence, a 'mind-body' problem as first outlined by Descartes and his notion of 'I think, therefore I am'; the question being, how does the physical functioning of the brain give rise to 'raw feelings' or experience?A number of theories have attempted to address consciousness. For example, according to Baars (1988, cited in Braisby, 2002), consciousness arises from autonomous processors, working in parallel, sending information to a global workspace that then broadcasts information to other processors. He suggests that consciousness corresponds to the contents of the workspace. Whilst this theory explains some aspects of conscious and unconscious cognitive functioning, it does not explain why or how this global workspace information gives rise to experience.Damasio (1999, cited in Braisby, 2002) suggests that core consciousness arises from representing relationships between representations of the body and representations of the external world.

He proposes that an extended consciousness arises from the long term storage of core consciousness. However, as with Baars's theory, this gives no explanation as to why or how we get the 'raw feel' or experience. Nagel (1974, cited in Braisby, 2002) proposed that consciousness always involves an 'I' point of view, and that when we talk of consciousness we mean that "there is something it is like to be...For example, "What is it like to be a bat? " How can we know what it is like to be a bat when we are not the subject of its consciousness? It is this intrinsic character of consciousness that produces the difficulties in giving objective and scientific accounts on the topic.

Because of these difficulties in explaining how physical processes in the brain give rise to subjective experience, sometimes known as the problem of qualia, Chalmers (1995) distinguishes phenomenal consciousness from other aspects of consciousness or 'the easy problems', and calls this the hard problem.He proposes that experience may be just a fundamental feature of the physical universe, arguing that all objects possess non-physical fundamental features such as mass or electromagnetic charge, as well as physical features, and proposes that they also have the added feature of experience. However this does not explain how these experience features combine in the brain to produce the 'raw feel' of consciousness. Nor does it explain why other physical objects such as a stone do not achieve this consciousness.Given the non-physical properties of qualia, they cannot be scientifically measured to determine whether or not they actually exist, consequently, philosophers have designed thought experiments in order to make us question our thinking and concepts.

One such thought experiment concerns the 'philosophers zombie' which asks us to consider creatures that are identical replicas of human beings that behave the same in every detectable way, thus there is no way of telling them apart from 'normal' humans. Are these zombies conscious?If we expect the zombie not to have consciousness, it suggests that consciousness is not part of the physical composition of an organism. Conversely, if we anticipate that they would have consciousness, it implies that a replica of a conscious human being would have to yield a conscious zombie, thus consciousness must be linked to the physical brain. This type of thought experiment can help us to work out the implications of our thinking as illustrated in the case of Ken Parks (cited in Bearsley, 2000). During the 1980s in Canada, Parks committed an atrocious killing whilst sleepwalking.

The Canadian legal system assumed somnambulism to be a state of automatism, where the individual has no awareness or control over his or her behaviour. Thus, the courts decided that, there could not have been any intent to commit murder, as Parks had no awareness or control over what he was doing, therefore he should be acquitted. This suggests that during sleepwalking, humans are in the same state as a zombie; they are without phenomenal consciousness, which implies that consciousness does not arise as a result of the brain and its physical state.Some would argue that there is no such thing as phenomenal consciousness.

For example, Dennet (1988, cited in Braisby, 2002) rejected the idea, saying that there are simply no qualia at all. He suggests that we simply assume that something else exists over and above the processes that we can be describe implying that it is our language that misleads us into thinking that phenomenal consciousness exists, and is therefore just a conceptual confusion. This idea however, would appear to be 'the easy way out'. McGinn (1989, cited in.

Braisby, 2002) on the other hand, argues that consciousness may just be so complex that it transcends our abilities to explain it, suggesting that we are 'cognitively closed' with respect to the phenomenon. Consciousness involves a number of aspects. For example access consciousness, which involves access to information from different kinds of mental processes; monitoring consciousness that involves monitoring and reflecting on our own actions and mental states; self consciousness that involves a concept of 'self' and its use in thinking and reflecting on oneself.Whilst we can gain some insight into consciousness through studies into neglect, blindsight or somnambulism, it is difficult to explain how the physical brain relates to the mind and the intrinsic, 'raw feel' associated with consciousness.

Thus, due to this intrinsic, qualitative and subjective nature, which is difficult to explain scientifically, phenomenal consciousness has been called 'the hard problem' of this area. So as yet, there is no explanation of why or how experience arises from a physical basis or indeed, why experience should arise from physical processing at all.