neuroscience

The concept of consciousness is extremely elusive, there are no concrete operation definitions and despite the enormous amounts of research on the subject throughout history.  Many aspects of what would be considered conscious perception are constructive; the mind seems to create parts of the environment, just as it perceives the environment.  These constructive processes of the mind are evoked when we dream, during hallucinations whether drug induced or resulting from a psychosis or neuropsychological disorder, and during conscious awareness.  Much can be ascertained about the constructive nature of consciousness from these realms of subjective experience.  Indeed, these three areas of psychology are historically controversial, giving even more weight to a review of their processes in light of the overall tenets of conscious perception.  These areas apply primarily to perception in the visual modality; therefore, the tenets of vision will be a large aspect of the discussion of the creative nature of consciousness.  These facets are but limited sources of information about constructive conscious perception, and the puzzle of consciousness has many pieces to be yet completed. 

REM Sleep and Dreaming

Dreaming is perhaps the most important of the constructive processes that can be used to study the constructive nature of consciousness.  Historically, it has been misunderstood and misinterpreted as symbolic representation of repression within the psyche, as a portal to an alternate dimension, and even as a predictor of future events.  Many viewpoints have been taken on the nature of dreams; however, this process is far different than most early researchers could have realized.  With new technological advances in the realms of neuropsychology, we can uncover some of the basic physiology of REM sleep, in which the majority of dreaming occurs.  Another aspect of dreaming and REM sleep that provide information upon the constructive nature of the mind are the multitudes of sleep disorders and large amounts of clinical research done on the nature of sleep. However, the subject of the importance of dreams is still under debate.  Dreams are constituted of sensations and emotional content, usually perceived as real by the dreamer (Dang-Vu, et al., 2005).  Most dreams are weird, non-linear narratives that are instable in terms of time, places, and people, and are most often forgotten upon waking.  Most of the information that will be used to discuss the tenets of consciousness can be viewed in terms of dreams; hallucinogens and neuropsychological disorders are most aptly depicted as being within a dream, due to the disorganization and erratic functioning of the mind during these conditions.  Dreaming is the first step into the realm of the mind’s active constructive of the environment.  Since dreaming occurs primarily in REM sleep, the physiology of REM sleep is intrinsic to the understanding of dreams.

REM sleep is a highly complex phenomenon.  It is most often associated with vivid dreams and high levels of brain activity (McCarley, 2011).  The first cycle of REM sleep usually takes place around 70 minutes after falling asleep and is defined by fast, low-voltage EEG activity, the suppression of motor movement, and the occurrence of rapid eye movements (McCarley, 2011).  The first REM period of sleep tends to be shorter, with increasingly larger amounts of REM as the sleep cycle persists throughout the night and delta waves (deep sleep) diminish.  REM sleep is present in all mammals and some birds (McCarley, 2011).   This insists of an evolutionary importance of REM sleep, which is the view put forward by this paper.  The size of the animal also seems to be correlated to the necessity of REM sleep, because elephants have the longest cycles of REM stage sleep.  In the uterus, mammals spend approximately 50 to 80% of their time in REM sleep, and animals born prematurely have much higher rates of REM sleep (McCarley, 2011).  As development continues, the percentage of REM sleep declines.  The facts highly support the necessity of REM sleep for nervous system development and many scientists believe that it can predict synaptic density.  REM sleep facilitates brain development by increasing the amount of nervous tissue and promoting the psyiological maturity of the existing tissue (Chiş, 2009). 

The physiology of REM sleep would infer that this process is completely necessary for what can be described as consciousness, because the definition of conscious beings seems to be limited to the groups of animals that experience REM sleep.  J. Allan Hobson (2009) has proposed a two level theory of consciousness that would explain the differences between what has historically been called alternate states of consciousness.  The primary level of consciousness, which animals experience, is emotions and perceptions of the outward environment.  But the second level of consciousness, which is applicable mainly to human beings, is language, reflective self-awareness, abstract thinking, volition, and metacognition.  The dream world that is experienced primarily in REM sleep would be described as a primary consciousness, whereas waking experience for human beings would be the secondary level of consciousness.  But in order to understand how the secondary level of consciousness develops, further study of the mechanisms of REM sleep and dreaming must be examined.  Indeed, the two processes might be physiologically linked.

Despite the general notion that REM sleep is equitable to dreaming, dreaming can occur outside of the REM stage of the sleep cycle.  The REM dream relationship is not concretely linked; dreaming occurs without REM mechanisms and rather depends on the cortical activations of dream states (Takeuchi, 2005).  The solution that Takeuchi (2005) proposes to this dilemma is that the REM mechanisms underlying dreaming can take place outside of REM sleep.   This would indeed support dreamlike states while awakened or with the effects of a neuropsychological disorder or hallucinogenic substance.  During REM sleep, the cortex has highly increased activity and a blood flow rate over 200% higher than in the wakened state (Chiş, 2009).  REM sleep is considered to be an activation of many normally inhibitory brain structures, which is one of the reasons why dreams are so disorganized and lacking in an absolute structure.  REM sleep is regulated by the pontine brainstem, which is an evolutionarily ancient structure (Hobson, 2009).  This would infer that REM sleep is not equitable with dreaming and that although dreaming requires the cortical activations that occur during REM sleep, dreaming is a more complex and intricate phenomenon.

Originally, dreams were thought to carry mystical power from an alternate dimension or from supernatural beings.  Dreams were sent for a variety of reasons, not the least of which were predictive of future events in shamanistic cultures.  The ancient Greeks had an entire religious tradition of oracles and prophets that would use dreams and psychosis-like visions to allow them to see into the future.  Indeed, philosophers such as Heraclitus and Aristotle rejected such claims and suggested that the dreams were subjective and created by the mind.  These traditions continued until empirical evidence on dreaming began to arise in the early 19^th century.  Sigmund Freud, the inventor of psychotherapy, proposed that REM sleep and dreaming was meaningful, related to mental functioning, and could be interpreted in terms of conscious awareness (Franklin & Zyphur, 2005).  Many of his theories are almost entirely disregarded by the scientific community.  However, an evolutionary analysis of dreams should not disregarded or considered outside the scope of scientific study (Franklin & Zyphur, 2005).  Many of the popular beliefs of dreaming are also false.  Despite the popular notion that dreaming occurs only in REM sleep, it has been known to occur during other sleep stages, and even during woken consciousness (Dang-Vu, et al., 2005)  REM is the most highly correlated with dreamful states and therefore is the basis upon which the foundation for the functioning of dreaming must be based.

Dreaming is a prevailing facet of conscious experience that is associated with specific brain states and occurs spontaneously for several hours each night (Schartz, Dang-Vu, Ponz, et al., 2005).  The problem with studying dreaming is that it is completely subject and unquantifiable.  This makes it extremely difficult for empirical evidence to be obtained.  However, there are well delineated cognitions, emotions, and perceptions of experience while dreaming which suggests that there are specific and common neural patterns of activity occurring while asleep (Shwartz et al., 2005).  REM is characterized by sustained cerebral activations, high cortical energy and blood flow and activations of certain areas of the brain (Dang-Vu, et al., 2005).  The brain areas that seem to activate during REM are the potine tegmentum, thalamic nuclei, and the limbic and paralimbic structures (Dang-Vu, et al., 2005). Takeuchi (2005) described REM as showing activation of the pontine tegmentum, amygdala, paralimbic cortex, and parietal operculum; and deactivation of the prefrontal cortex, motor output, and sensory input, and a shift towards an internal stimulation source.  He also showed that the serotonin pathways modulate activation of the cholinergic neurons over aminergetic neurons in the pons, which causes the aminergetic system to demodulate and the cholinergic modulation in the basal forebrain and ganglia (Takeuchi, 2005).  These are the physiological states corresponding to dreamlike experiences.  These specific brain areas are highly linked to memory, which may be why traces of awakened memory are active while asleep.

The actual role that dreams play in the states of waking consciousness is not fully understood or explainable with current empirical data.  Some of the more contemporary theories are that dreams are a kind of mental rehearsal, hence why many dreams are constituted of the experiencer escaping from imaginary assailants, forgetting certain things only to remember them upon waking, or social situations that could occur in waking life (Franklin, & Zyphur, 2005).  Basically what these theories state is that the dream states have evolved for the purpose of providing the brain with preparation for mental activity during waking consciousness.  Unfortunately, this data is merely speculative, and no real function can be assigned to the dream-state besides the physiological regulation of neural activity and plasticity.  This is not to say that dreams are not useful, only that these hypotheses are not currently empirically testable, leaving them somewhat useless, however compelling they may be.  The brain functions of the activation and deactivation that dynamically oscillate in REM sleep for waking cognition remain unclear (Braun, 2009).

Using Hubson’s (2009) separation of primary and secondary consciousness, the development of human and animal consciousness can be analyzed.  There is a large amount of REM sleep in early life; in humans REM sleep peaks in the third trimester of gestation and decreases significantly after birth, as time awake and cognitive capabilities increase.  Therefore, the primary consciousness declines and the secondary consciousness grows with the development of cortical functioning and the capacity for prolonged periods of wakefulness (Hubson, 2009).  REM sleep occurs at the earliest stages of development; however, it is likely that dreams do not manifest themselves until brain development has reached a point were narratives of subjectivity become possible; in human beings this is around ages five to eight (Hubson, 2009).  Examination of fetal development will provide further insight into the discussion of conscious experience and how REM sleep relates to dreaming.

In the uterus, the human fetus alternates between states of REM and cortical deactivation (Hubson, 2009).  About fifty to eighty percent of the time in the womb is spent in REM sleep (McCarley, 2011).  It is also believed that this autoexcitation that occurs during REM sleep may provide the framework for what is known as waking consciousness (Hubson, 2009).  Evidence has also been provided that the activity of REM sleep facilitates the development of the visual system, especially in specialized development of the striate cortices (Dang-Vu, et al., 2005). 

During REM sleep, temporo-occipital activations were observed using fMRI imaging techniques; these areas included the inferior temporal cortex and fusiform gyrus; however, the functional relationship between the activation of extrastriate cortex caused the deactivation of the striate cortex (Dang-Vu, et al., 2005).  These activities combined the with paralimbic/limbic brain activations create a system where internal information processing occurs in a closed system, not involved in input from the environment or output to the environment.  It is these primary structures in the cortex that can be associated with the disorganized brain functioning exhibited in dreams and that results in highly charged emotion, visual disorganization, and inability of the brain to recognize that it is asleep. These activations combined with deactivations of the association cortices in the inferior and middle lateral prefrontal, the inferior parietal lobule, and the temporo-parietal regions create the effects of dreaming on the brain (Dang-Vu, et al., 2005).  These are the neural correlates known about the phenomenon of dreaming.

The cortical processes activate what is creates the mental states known as dream.  These are highly creative conscious experiences with enormous amounts of cortical activation that differs greatly from waking perception.  During the past decade, the neuroimaging techniques developed has vastly increased the knowledge of the cortical functioning of REM sleep and dreaming; giving science a fundamental knowledge of why the cortex creates input while simultaneously disallowing output of the cortex (Maquet, et al., 2005).  This realm of subjective experience has implications for the consciousness of all mammals and some birds that fit the category of conscious beings, in the first level that Hobson (2005) describes.  The waking consciousness creating the secondary features of Hobson’s protoconsciousness theories are probably exclusive to humans, because of the highly evolved cortical structure that accompanies our brains.

There are ways of altering consciousness to increase the productivity of the REM sleep received.  It seems that yoga is one of the ways, as well as different types of meditation and breathing techniques.  The practitioners of yoga can experience enhance theta-alpha brainwaves and enhanced REM sleep with regular practice (Sulekha, et al., 2006).  This could be an indication that yoga leads to a type of heightened consciousness, because of the types of brain activity involved with REM sleep, and the increases in the brain activity of yogic practitioners.  This is one way that REM sleep may be improved.  Another known way to increase the amount of REM sleep obtained is exercise and mental activity during the day.  REM sleep is essential to conscious functioning and the secondary aspects of consciousness.  Studies done with rats have shown death due to lack of REM sleep, using the disk-over-water method (Cirelli, & Tononi, 2011).  REM sleep is used to regulate cortical functioning and animal studies have shown marked decreases in the functioning of the cortices of REM sleep deprived rats on a cellular level (Cirelli, & Tononi, 2011).  The reasons that Circelli and Tonomi (2011) provide for this is that the protein synthesis and neural plasticity in synaptic consolidation and downscaling are not able to occur; this also suggests that sleep plays a role in the maintenance of the cortical membrane, including glial cells.  REM sleep is an indispensible aspect of consciousness and is perhaps the most important state for the maintenance of the secondary traits of consciousness that human beings experience.

Neuropsychological Disorders

There are several neuropsychological disorders that can provide insight into conscious experience.  The disorders of particular interest to the realm of cognitive construction of perception are those that are influenced by hallucinations, especially visual hallucinations, because of their similarity to dreaming.  These disorders are important for understanding how the perceiver constructs the environment.  They can provide insight into the nature of the construction consciousness and how it manifests itself.  The disorders that will be examined pertaining to this constructive perception are Guillain-Barré syndrome, schizophrenia, narcolepsy, and insomnia.

Guillain-Barré syndrome (GBS) is an acute psychological disorder with sensory and motor impairments (Cochen, et al., 2005).  Many of the patients with this disorder experience mental status disorders, including personality changes, mental disturbances, hallucinatory experiences and oneiric states, dream-like scenic hallucinations, and psychosis.  This syndrome affects the peripheral nervous system; however, the central nervous system is also largely affected, as evidenced by the mental abnormalities (Cochen, et al., 2005). 

The dreams experienced by a small portion of the patients with mental status abnormalities and the dream state would impede upon their waking consciousness.  Many also experienced hallucinations of objects and highly emotional dreams while asleep, perhaps evidencing abnormalities in the amygdala system and its processing and regulation of dreams.  Many patients would experience body illusory body tilts and some even reported sensations of weightless floating (Cochen, et al., 2005).  Many patients saw small hallucinations of goblins, tiny moving figures of various sizes.  These hallucinations generally occurred when the patients closed their eyes, perhaps having to do with the visual cortex’s inability to inhibit activity.  The quality and amounts of sleep were poor in all groups and was fragmented and unstable.  The REM sleep of patients was extremely abnormal and would impede upon the other sleep stages (Cochen, et al., 2005), as it was probably also impeding upon their woken consciousness.  These sufferers of GBS had altered perceptions of the world, probably a result of the severe impairments of the cortical network underlying REM sleep, which resulted in the hallucinations, and lack of the functionality of secondary features of consciousness described by Hobson (2005).

The second disorder that provides information on the consciousness is Narcolepsy.  This disorder is most often conceptualized as affecting regular sleep patterns, especially on REM sleep.  There seems to be a dramatic decrease of the time interval between the onset of sleep and the first cycle of REM sleep, which would support the increase of pressure of the need for REM upon the mind (Dahmen, et al., 2002).  Hallucinations are often experienced before falling asleep and after waking, decreased muscle ton as a result of impairment of the motor system.  Sleep paralysis and sleep attacks can often occur in the disorder.  This disorder is considered a sleep disorder because during the onset of these symptoms, encephalographic data has shown that REM sleep waveforms are present (Dahmen, et al., 2002). 

Schizophrenic hallucinations have also been linked to the intrusion of REM sleep into the waking consciousness.  This REM sleep intrusion into waking life has also been implicated in Parkinson’s disease, including hallucinations, delusions, and REM sleep intrusions (Diederich, et al., 2007).  Schizophrenia and narcolepsy are often hard to differentiate in clinical diagnoses because of the completely altered sleep patterns and the intrusions of REM sleep into waking consciousness (Dahmen, et al., 2002).  This provides evidence that the cortical network associated with REM sleep are malfunctioning, specifically that they are not inhibited as they usually are during waking consciousness.  This also evidences the idea that REM sleep is the foundation upon which the secondary traits of waking consciousness are supported. 

Insomnia is believed to occur because of the increased activation of the limbic and paralimbic regions of the brain (Desseilles, 2008).  Depression is the most common primary diagnosis in patients suffering from insomnia (Desseilles, 2008).  The hyperarousal associated of the cortical mechanisms with both disorders suggest that the sleep dysfunction is due to malfunction of the cortical sleeping system.  The increased density of REM sleep occurrence also provides evidence for this hypothesis.  Insomnia can be highly debilitating to waking consciousness and inhibits many of the cognitive capacities of the secondary traits of consciousness, providing further evidence for Hobson’s theory of consciousness.

These psychological disorders provide some insight into the importance of dreaming as a cortical framework for consciousness.  These deviations upon what would be considered normal human cortical functioning provide evidence of the structural dependency of the brain upon the cortical system underlying REM sleep, and therefore, the subjective experiences of consciousness.

Hallucinogenic Substances

            There are several hallucinogenic substances that can provide further insight into the realm of consciousness.  Lysergic Acid Diethylamide and psilocybin are the two substances that have historically been used to alter waking consciousness.  These two substances have extraordinary impacts upon functioning and alter the state of consciousness to something that is hardly recognizable as either waking or dreaming states of conscious subjective experience.  Instead, these states can be viewed as a kind of limbo in which the cortical mechanisms are altered to create a pseudo-dreamlike state.

            LSD was used largely in the earlier 20^th century as an aid to psychotherapy.  The primary changes that occur when under the influence of this substance are illusions, pseudo-hallucinations, synesthesia, alterations of thinking, and inability to correctly perceive time (Passie, et al., 2008).  During this state, motor functions are impaired and attention and concentration are significantly inhibited.  Some scientists have equated the regression of intellectual function under LSD to that of an ontogenetically younger state of consciousness (Passie, et al., 2008).  However, overdoses of LSD can create persisting hallucinations that the DSM recognizes as Hallucinogen Persisting Perceptual Disorder (Iaria, et al., 2010).  This data is supportive of the idea that LSD creates a pseudo consciousness that is a kind of limbo between the consciousness of dreams and the consciousness of waking, combining features to create an altered state of consciousness.  This is consistent with the previous data on the correlates of consciousness as created by a cortical system; indeed, consciousness is a direct result of brain activity of certain complexes.

            Psilocybin can also provide interesting commentary on the nature of conscious perception.  Many of the effects of psilocybin are consistent with those of schizophrenia, especially patients with acute schizophrenia experiencing different types of hallucinations (Mayfrank, et al., 2002).  This hallucinogen has been found to induce hyperfrontal patterns of activation in cerebral blood flow.  Psychomotor retardation was also observed by decreased reaction times in a spatial cueing task (Mayfrank, et al., 2002).  This decrease in cognitive functioning is evidence that psilocybin is also a drug that can induce a pseudo dream state and that the higher processes of attention and the secondary aspects of consciousness are specific to the complex brain organization of human beings.

            These drugs provide evidence that consciousness is but a result of neural functioning and that the specific brain areas of human beings create what humans know as subjective conscious experience.  These states of limbo allow for an analysis of consciousness that includes almost all aspects of waking and dreaming perceptions and provide insight into why consciousness occurs and how it manifests itself.

Consciousness and Cognition

            Evidence for consciousness being a state supported by brain mechanisms and cortical inhibitions and activations that produce what human beings perceive as subjective consciousness.  It can be said that this does not provide for the amount of power that consciousness provides life, nor the potential of the individual within his/her subjective experience.  Ervin Laszlo (2006) attempts to redefine this paradigm by shifting the concept of reality with what is scientifically known and proven about quantum mechanics.  Much of what we consider to be real is actualized, that is, it occurs in time and space.  However, one of the problems with this view is that potential states are also a part of reality.  What quantum physics denotes as virtual, can actually be considered reality, because the inability to predict future events (at the level of the quark) creates potential states that are sustainable.  Potential states do not need to be considered mind like, transcendent, or mysterious.  These are simply physical events at the level of a quantum wave that are not actualized.  This contributes to a fairly stimulating view of consciousness.

            Virtual states are mind like events associated with the potential to become actualized (Laszlo, 2006).  Instead of viewing these are virtual states, if we were to classify these as unrealized physical events, then the consciousness like events become an intrinsic part of the universe.  This creates a dichotomy for two aspects of the same stuff, instead of two different kinds of stuff, which can mediate the mind-body problem experienced by philosophers and psychologists alike.  Overall, this view of consciousness as intrinsic in the universe provides structuralists with the ability to explain consciousness in terms of highly complex physical events that may or may not be actualized.

            The fundamental tenets of consciousness are the perception and emotional reactivity to the environment.  With this definition, science can solve the consciousness problem in terms of secondary and primary characteristics, involving actualized and potential states that makes up the subjective experience that each human being experiences (if he/she is conscious).  This provides insight into the importance of the knowledge and understanding of cortical mechanisms and brain functionality.  Consciousness will continue to evolve alongside life, with human beings at the forefront of the evolutionary race until the human race evolves yet again into the next stage of the collective subjective experience known as life.

References 

Chiş, I. E. (2009). The evolution of brain waves in altered states of consciousness (REM sleep and meditation). Human & Veterinary Medicine, 1, 95-102.

Cirelli, C., & Tononi, G. (2011). Molecular neurobiology of sleep. Handbook Of Clinical Neurology / Edited By P.J. Vinken And G.W. Bruyn, 98191-203.

Cochen, V. V., Arnulf, I. I., Demeret, S. S., Neulat, M. L., Gourlet, V. V., Drouot, X. X., & … Bolgert, F. F. (2005). Vivid dreams, hallucinations, psychosis and REM sleep in Guillain–Barré syndrome. Brain: A Journal of Neurology, 128, 2535-2545.

Dahmen, N. N., Kasten, M. M., Mittag, K. K., & Müller, M. J. (2002). Narcoleptic and schizophrenic hallucinations: Implications for differential diagnosis and pathophysiology. The European Journal of Health Economics, 3(Suppl 2), S94-S98.

Dang-Vu, T. T., Desseilles, M. M., Albouy, G. G., Darsaud, A. A., Gais, S. S., Rauchs, G. G., & … Maquet, P. P. (2005). Dreaming: A neuroimaging view. Schweizer Archiv für Neurologie und Psychiatrie, 156, 415-425.

Desseilles, M., Dang-Vu, T., Schabus, M., Sterpenich, V., Maquet, P., & Schwartz, S. (2008). Neuroimaging insights into the pathophysiology of sleep disorders. Sleep, 31, 777-794.

Diederich, N. J., Leurgans, S., Wenqing, F., Chmura, T. A., & Goetz, C. G. (2008). Visual hallucinations and symptoms of REM sleep behavior disorder in Parkinsonian tauopathies. International Journal of Geriatric Psychiatry, 23, 598-603.

Franklin, M. S., & Zyphur, M. J. (2005). The Role of Dreams in the Evolution of the Human Mind.Evolutionary Psychology, 359-78.

Gouzoulis-Mayfrank, E., Thelen, B., Maier, S., Heekeren, K., Kovar, K., Sass, H., & Spitzer, M. (2002). Effects of the hallucinogen psilocybin on covert orienting of visual attention in humans.Neuropsychobiology, 45, 205-212.

Hobson, J. (2009). REM sleep and dreaming: towards a theory of protoconsciousness. Nature Reviews Neuroscience, 10, 803-813.

Iaria, G., Fox, C., Scheel, M., Stowe, R., & Barton, J. (2010). A case of persistent visual hallucinations of faces following LSD abuse: a functional Magnetic Resonance Imaging study. Neurocase (Psychology Press), 16, 106-118.

Laszlo, E. (2006). Quantum and Consciousness: In Search of a New Paradigm. Zygon: Journal of Religion & Science, 41, 533-542.

Maquet, P., Ruby, P., Maudoux, A., Albouy, G., Sterpenich, V., Dang-Vu, T., & … Laureys, S. (2005). Human cognition during REM sleep and the activity profile within frontal and parietal cortices: a reappraisal of functional neuroimaging data. Progress In Brain Research, 150219-227.

McCarley, R. (2011). Neurobiology of REM sleep. Handbook Of Clinical Neurology / Edited By P.J. Vinken And G.W. Bruyn, 98151-171.

Passie, T., Halpern, J., Stichtenoth, D., Emrich, H., & Hintzen, A. (2008). The pharmacology of lysergic acid diethylamide: a review. CNS Neuroscience & Therapeutics, 14(4), 295-314.

Picchioni, D., Killgore, W. S., Balkin, T. J., & Braun, A. R. (2009). Positron Emission Tomography Correlates of Visually-Scored Electroencephalographic Waveforms During Non-Rapid Eye Movement Sleep.International Journal of Neuroscience, 119, 2074-2099.

Schwartz, S. S., Dang-Vu, T. T., Ponz, A. A., Duhoux, S. S., & Maquet, P. P. (2005). Dreaming: A neuropsychological view. Schweizer Archiv für Neurologie und Psychiatrie, 156, 426-439.

Takeuchi, T. (2005). Dream mechanisms: Is REM sleep indispensable for dreaming?. Sleep & Biological Rhythms, 3, 56-63.