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Cocaine and Perception: Does cocaine affect or alter our senses?
by Christopher Davis
Abstract
The purpose of this study is to determine the affect cocaine has on the brain’s ability to perceive its surroundings through audio and visual input. Three studies involving the administering of cocaine to rats, baboons, and humans were examined along with articles detailing the chemical reactions involved in producing a cocaine 'high.' The conclusion drawn from the results of the studies and the technical articles is that cocaine intake does not affect or even come close to altering the way the brain perceives its surroundings on the auditory or visual levels. The 'high' produced by cocaine comes without any hallucinatory or sense altering effects and operates more like the pleasure derived from eating a particularly tasty meal or winning a difficult game, unlike the 'high' produced during the use of marijuana. This study also indicates that the only sense altering effects produced by cocaine use come during periods of withdrawal and from physiological damage done by the chronic use of the drug, not from the chemical properties of the drug itself.
Cocaine belongs to a group of drugs known as psychoactive drugs that alter the way the brain processes information. More specifically, it is a member of the family of drugs known as 'stimulants' and is able to cause feelings of euphoria, invincibility, energy, arousal, lack of inhibition, and peacefulness (Resnick, Kestenbaum, & Schwartz, 1976 ). The active ingredient in cocaine is cocaine hydrochloride and it can be ingested through the inhaling of its powder form, through direct insertion into the bloodstream via a water solution and syringe, or through inhaling of cocaine powder’s heat released vapor, known as 'crack' for the crackling sound it produces when being heated (cocaine.org, 2003). It comes from the paste created by crushing the leaves of the coca plant, which happens to thrive in the tropical climates of South America where almost all of the cocaine trafficked in the US originates (http://unesdoc.unesco.org/images/0011/001158/115833e.pdf.). Cocaine encourages the release of a plethora of chemicals in the body and brain and also encourages the lingering of some active chemicals in the brain much longer than they normally would remain active; but how does this affect human perception and normal brain activity?
Direct studies can be done where a group of people are repeatedly administered cocaine and then given a series of tests to measure the various effects, tests on animals are also done. In a study performed by Hienz, Weed, Zarcone, and Brady, the effects of cocaine on auditory discrimination in baboons is explored in an effort to determine what cocaine ingestion changes in an auditory system similar to a humans. Their method was to train several baboons to respond to a ready signal of a flashing light so that they would press and hold a lever to stop the light from flashing. Once the light stopped flashing they were trained to hold it until they heard a certain tone or voice sound, the reward for a correct tone or voice recognition being an immediate administering of cocaine into their muscle tissue and a resumption of the experiment with the flashing ready light. The penalty for releasing the lever for the incorrect tone or voice sound being an immediate 'time out from the exercise' followed by cocaine administration and exercise resumption with the ready light (2003). The researchers found that as the trials progressed the baboons began to discriminate less and less between correct and incorrect responses. The mandatory time out period lost its deterrent characteristics as the baboons became more and more focused on obtaining the next cocaine administration. The response time to the tone or voice sound dropped significantly in the baboons being administered cocaine as the trials progressed, but did not drop nearly as sharply in the baboons being administered placebo (Hienz, Weed, Zarcone, Brady, 2003). At the conclusion of Heinz et. al.s study they were able to conclude that cocaine significantly reduced the time it took for the baboons to respond to the aural stimulus, but also significantly reduced the accuracy of their responses. When the correct or incorrect tone was sounded the baboons began to discriminate less and less between which tone to respond to and which one not too, seeming to exhibit a greater desire to keep the pleasurable impetus of reward going and also seeming to exhibit a greater disregard for the punishment of time-out from the experiment for wrong responses. The study of the baboons given doses of cocaine and then presented with a test revealed what many surveys of regular cocaine users have stated: when taking cocaine, one feels exhibit more focused, more energetic, and more capable (directly after ingestion) because, in fact, one is more focused, energetic, and capable, but one is also more prone to errors and lapses of motor capability because of other chemicals released by the presence of cocaine in their blood (http://www.erowid.org/experiences/exp.php?ID=18230, 2003).
Cocaine changes the presence of neurotransmitters in the brain causing four (or more, but typically four) of these neurotransmitters to be available in altered amounts. Dopamine, a transmitter that controls many of the pleasure pathways in the brain, is caused to linger longer close to the post synaptic receptors with cocaine hydrochloride binding to the transporters at the pre synapse and blocking their ability to pump dopamine away from the receptors, inhibiting its re-uptake (http://www.drugabuse.gov/NIDA_Notes/NNVol14N2/Cocaine.html). This leads to the increased sense of arousal and ability in cocaine users once they ingest the drug, thanks to the over abundance of dopamine. They feel they can hold more active conversations and enjoy an extreme clarity of thought, feeling as though they are able to take on anything and anyone. Acetylcholine is a neurotransmitter that triggers the flexion of muscles, and is also affected by the presence of cocaine.. The presence of cocaine in the bloodstream and muscle tissues (as well as the brain) increases the release of acetylcholine at the site of muscles, creating spastic movement, muscle seizures, involuntary tics and loss of physical control of the muscles. Cocaine also encourages the release of serotonin, creating the heightened sense of euphoria and peace, but it also agitates the adrenal glands causing the release of adrenaline which triggers the onset of sudden power, strength, focus, and physical capability (http://cocaine.org/misc/monoamines.html). Cocaine is a very complex and unpredictable drug, triggering sudden death in some first time users upon ingestion or even death that occurs several days after ingestion. The fact that it alters the presence of so many common and vital neurotransmitters in the human brain is what allows it to produce such profound mental states in the human mind (Wetli, Fishbain, 1985). Lower reaction times to a stimulus and increased physical response to that stimulus can be expected, but the chemical does not produce hallucinatory states like other stimulants. Cocaine enhances the body’s perception of outside input and shortens the time it takes to respond to it while also intensifying the response and the sense of pleasure derived from the response.
Cocaine does not provide the same function as marijuana or LSD and does not have the same effect on the mind’s ability to perceive the signals produced by the brain’s sensory organs. Marijuana, for instance, has an active ingredient known as THC that binds to special cannaboid receptors in the brain, releasing neurotransmitters that produce sensations of being 'high,' giddy, euphoric, and the experience of hallucinations (http://www.cannabisculture.com/whatsnew/chocobliss.html). Marijuana directly affects the mind’s ability to perceive its surroundings and respond to them, but cocaine only changes the way the mind responds to its surroundings (not how it perceives them) (http://www.acde.org/common/Marijana.htm). Cocaine does not affect or alter the body’s senses. Everything that a non-user of cocaine sees, feels, smells, tastes, and hears is exactly the same as a user would sense; however, what is affected and altered is how the user’s brain responds to the sensory input and how he classifies the input as pleasurable, painful, neutral, or irrelevant. This is largely why it is classified as a stimulant and not a hallucinogen.
The argument can still be made that cocaine can in fact impact the body’s ability to perceive its surroundings, but this argument is only marginally valid in cases of addiction when the drug is withheld from the chronic user. Having used the drug for so long to alter the balance of neurotransmitters in the brain a tolerance is quickly built up in which the brain copes with the consistent interference of cocaine hydrochloride in its system by changing how much of the affect transmitters it will produce and release. Once these changes are made the brain literally becomes hard wired to operate with any degree of normalcy only when the drug is present. In addicted users this condition is fulfilled all of the time, but when it is not fulfilled symptoms of withdrawal quickly set in. These symptoms include acute paranoia, mood swings, convulsions and psychosis. With the pleasure receptors, muscle activators, sleep regulators, and fight or flight systems all malfunctioning in the absence of much needed cocaine hydrochloride the brain begins to malfunction and perceive danger, tension, and signs of aggression from other people when none of these things are actually present. Hallucination can set in along with schizophrenia and insomnia because of the disrupted serotonin and dopamine levels. All of the symptoms are clear changes in the way outside input is being perceived and processed, validating the fact that the with-holding of cocaine from a dependent user can alter his senses (http://www.druglibrary.org/schaffer/Library/studies/cu/CU35.html, 2003). The truth remains that outside of its absence cocaine cannot produce these altering effects except in cases of pre-birth exposure, such as the case of a study performed by Tan-Laxa, Sison Switala, Rintelman, and Ostrea in which infants exposed to cocaine while still in the womb suffered auditory defects due to altered developmental patterns, side-effects of cocaine abuse during pregnancy.
References
http://www.aros.net/~lambo/coca/coca.htm
http://www.cocaine.org
http://unesdoc.unesco.org/images /0011/001158/115833e.pdf
http://www.erowid.org/experiences/exp.php?ID=18230
http://www.drugabuse.gov/NIDA_Notes/NNVol14N2/Cocaine.html
http://cocaine.org/misc/monoamines.html
http://www.cannabisculture.com/whatsnew/chocobliss.html
http://www.acde.org/common/Marijana.htm
http://www.druglibrary.org/schaffer/Library/studies/cu/CU35.html
Resnick, R. B., Kestenbaum, R. S., & Schwartz, L. R. (1967). Acute systemic effects of cocaine in man: a controlled study by intranasal and intravenous routes.
Science, Vol. 195, pp 696
Tan-Laxa, M. A., Sison-Switala, C., Rintelman, W., & Ostrea, E. M. (2004). Abnormal auditory brainstem response among infants with prenatal cocaine exposure.
Pediatrics, Vol. 135, pp 357
Hienz, R. D., Weed, MR, Zarcone, T. J., & Brady, J. V. (2003). Cocaine's effects on detection, discrimination, and identification of auditory stimuli by baboons.
Pharmacology, biochemistry, and behavior, Vol. 74, pp 287
Wetli, C. V., Fishbain, D. A. (1985). Cocaine-induced psychosis and sudden death in recreational cocaine users.
Journal of forensic sciences, Vol. 30, pp 873
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