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Biology 202
2002 Third Paper
On Serendip

Schizophrenia, A Matter of Perception Part 2: Reality, What Reality?

Sook Chan

What is reality? To many, reality is the ability to validate a sensory experience with another sensory experience, for example, when one is able to touch what he sees, then that something is real. Yet, our perception, the collection of all our sensory inputs formatted into the framework of the mind, is unreal. A blue box is not really blue, but consists of waves transmitted to our visual receptors. What sounds like music is really a collection of vibrations, and smells are really different molecules interacting with our nasal receptors. Our perception does not correctly reflect the true identity of an object. The electromagnetic waves absorbed and transmitted off an aggregate of mass, manifests itself as a blue cube, and all our visual limitations allows us to see is a blue cube. If reality were defined as the existence of an object as we perceive it, then reality is unreal. There are many errors to the human experiences and the human mind because mankind needs the affirmation that information and facts are either right or wrong. Once upon a time, the world was the center of the universe, with mankind standing at its' pedestal. Even when evidence was present, it took many years before people then learned to accept a new form of thinking. So what we view as real and right today, may just be a summary waiting to be replaced. Yet, are we ready to accept a new reality?

Perception in itself varies greatly from one individual to another. No two people are the same, and no two people have the same fine tunings that discriminate the sensory environment. What our environment presents to our sensory receptors differs from what our brain presents to our perception. When presented with a painting of a blue cube, one person might notice the different textures of the paint and the background, while another might focus on the dimensions of the cube. As these images are transmitted to the brain, the schemata that is accessed by this input also varies from one individual to another. Jo may see the color blue and remember the time her father bought her a blue bike, bringing her back to happy childhood memories. The color blue may send a shiver down Bob's spine as he remembers the blue vodka bottle his alcoholic and abusive father used to drink. Where does one draw the line between reality and perception? And how does one determine which reality is more real?

We perceive the world around us through our sensory systems. However, there is no real format by which to generalize different individual's perceptions. When a stimulus from the external world is sent to the brain, it formats and contextualizes the information into something familiar and sensical based on the individual's schemata. So what happens when one's train of thought is fragmented and one's brain is unable to organize these fragments into a comprehensible pattern? Imagine if at times, your experiences become a slide show, fragments of experiences that do not come together. This is, in fact, how many people suffering from schizophrenia describe their experience (1). Schizophrenia is one of the most severe psychopathologies present today. Its causes are still vague, and the symptoms vary across a large spectrum. However, two generalized grouped of symptoms have been identified for schizophrenics: positive symptoms, and negative symptoms. Negative symptoms include lack of activity, anhedonia, and loss of interest. Positive symptoms include disorganized speech, hallucinations, and delusional experiences (1).

Individuals with schizophrenia experience many problems with combining and associating their different sensory inputs. They have a false sense of reality and are unable to interpret the context and of situations and the difference between reality and imaginary. Schizophrenics are also unable to provide context to fresh sensory experiences due to their inability to access old memories and schemata (2). Many schizophrenics remark that their surroundings seem unreal and their external sensory environment are altered from what they previously experienced. It has been reported that schizophrenics often receive their environmental surroundings in fragments of sensory input. Their perceptions lack chronology and order, and maybe, their perception does not fully represent reality. This results in visual and auditory hallucinations and impairments with information processing

"Everything is in bits. You put the picture up bit by bit into your head. It's like a photograph that is torn to bits in your head" (2).

Two types of hallucinations are commonly experienced by Schizophrenics: auditory and visual. Auditory hallucinations come in a form of voices speaking to the individual, commenting on his actions, music, and voices of others conspiring. Schizophrenics are often portrayed as a crazy man talking to himself. However, auditory hallucinations are valid and it is understandable as to why they occur so commonly amongst schizophrenics. As mentioned before, the sensory input of schizophrenic individuals, including sight and sound, are sent as fragments, with no chronology or order, to the brain. Normally, what we see and what we hear come together to the brain. However, there is a possibility that if what is heard and what is seen are sent as separate fragments, the brain conjures and fills in pieces of information that are missing. Auditory hallucinations may result from the brain's expectation of sounds associated with fragments of images received by the brain. This is a result of conditioning; the expectation that a certain image would be associated with a certain sounds (3). Auditory hallucinations activate an area of the brain known as the Heschl's gyrus, the same region involved in the perception of hearing (4). However, in a study done, the Heschl's gyrus was also activated when schizophrenic participants were asked to imagine a sound or voice (4). This indicates the possibility that auditory hallucinations result from an external stimulus, and so, schizophrenic auditory hallucinations do not generate internal stimuli differently from non schizophrenic individuals. They merely interpret external stimuli differently. An error in circuitry from within the brain regions may impair the processing of sensory input from the external environment. Also, there is a possibility that the "voices" they hear of people talking to them are their own conscious, automatic thoughts and inner speech perceived as external. This is probable occurence as there are many reports of auditory hallucinations by people who are placed in solitary confinement or isolation (5).

Visual hallucinations in schizophrenia involve animals, figures, or a delusional religious character. In the latter stages of the disorder, visual hallucinations may be accompanied with auditory hallucinations (6). Hallucinations and delusions are secondary conditions to the distortion of reality (6). One might say that hallucinations and delusions exists from the inability to correctly rationalize confusing situations from random fragments of information.

Schizophrenics also experience cognitive failures in information processing. Common knowledge and social interactions no longer have precise meanings to them. They fail in areas of social intuition and automaticity of social interactions (6). This is also characterized by deficits in memory tasks that engage prefrontal and medial temporal systems, both of which are abnormal in these patients (7). In a study, monkeys were administered with the drug phenycylidine to recreate the dopaminagenic activities of a schizophrenic's brain. The monkeys were presented with a transparent cube with a banana inside and a small hole at one of the faces. It was found that when the opening was turned away from the monkey, it kept grabbing for the banana in the cube, even though their hands kept banging into the cube wall. Researchers associated this cognitive impairment to the abnormal dopamine levels in the brains of these monkeys (9).

"I miss the natural way of taking things for granted" (8).

Patients with schizophrenia process irrelevant information that intrudes into their consciousness and causes distractibility. During a psychotic episode, the cognitive defect plays a major part. They are unable to organize inputs into a larger picture to provide context. Hence, schizophrenics fail to control the contents of their consciousness (2). The main question is what is the cause of this distractibility and flawed perception?
The prefrontal cortex and the hippocampus are the brain structures that are believed to be impaired in schizophrenic individuals (5). The prefrontal cortex elicits responses guided by internalized knowledge that include one's schemata and memory. The hippocampus stores memory and allows for its retrieval. It is the structural framework that provides the brain with a sense of context by binding together sites in the neocortex that represents the correct contextual framework (5). A strong correlation has been found between the prefrontal cortex physiological activation and the reduced hippocampus volume in schizophrenic subjects.

Much of the neurobiology of schizophrenia remains unknown. However, effective anti-hallucinating, anti-psychotic drugs such as clozapine target the dopamine receptors of the brain, indicating a possibility that dopamine D4 receptors may be a critical site of action (1). It has been summarized that the brain fills in the missing pieces of our sensory environment, making us see things that may not be there. A schizophrenic individual's brain is unable to correctly retrieve stored past experiences to format a current experience into context. Hence, the brain starts afresh, with no prior training of how to fill in the different fragments of sensory input. Schizophrenics experience an impaired sense of reality because as the brain is sticking the fragments of experiences together, it fills in pieces that are not there, making the individual believe in things that are out of context and out of reality.

"My perception of the world seemed to sharpen the sense of strangeness in things. In the silence and immensity, each object was cut off by a knife ... spaced off from other things. If you move it's frightening. The picture you had in your head is still there but it's broken up. If I move there's a new picture that I have to put together again." (2).

Are the perceptions of individuals suffering from schizophrenia unreal? If reality is defined as the "norm" way of viewing things, then yes. However, who is to say which and who's reality is real? One question that arises is that schizophrenia is substantially a genetically predisposed disorder. If this is the case, why is the gene coding for schizophrenia still so prominent? It has been identified that traits that underlie schizophrenia are found in many people who are not ill and who are among the most creative and succesfull members of society (10). These genes have been maintained in the gene pool by natural selection because of their beneficial effects of enhancing creativity (7). To quote David Horrobin, author of The Maddness of Adam and Eve: How Schizophrenia Shaped Humanity, "Without the genes which in combination cause schizophrenia we would be like Neanderthals or Homo Erectus-large brained, clever, but lacking that lust for change and creative spark that have so dramatically distinguished our species from our immediate predecessors." (7). It is because Schizophrenics have the gift to view things in a different light and angle, with no inhibitions and past paradigms standing in their way, that Schizophrenics are able to be creative. This creativity stems not from imagined visions or sounds, but from the reception of the external environment in a different manner. So remember, just because something isn't stored in your memory, does not mean that something is unreal or inexistent. To answer an age old question, when the tree falls in a forest far away, we do not hear the sound it makes, but the sound vibrations still exists.

(1)What happens to the body and brain of individuals with schizophrenia?
(2) Context and Cognition in Schizophrenia
(3)What causes them?
(4) Hearing voices
(5)Impaired recruitment of the hippocampus during conscious recollection in schizophrenia
(6)Cerebral activity associated with auditory verbal hallucinations
(7)The missing link
(8) Cause identified in Schizophrenic Hallucinations
(9)Schizophrenia clues from monkeys
(10)Eccentric Origins of Creativity

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