Drugs and their effect on Human Brain

Here are summaries of the effect of select street drugs on the brain. Some of the introductory information is derived from About.com. Select authoritative references for information about effects of drugs on the brain include: Drug Abuse in the Decade of the Brain, Gabriel G. Nahas and T. F. Burks, Eds., IOS Press, 1997. Drug Use and Abuse, Jean-Pierre Changeux, in The Brain by G. M. Edelman and J. Changeux, editors, Transaction Publishers, 2001. Heroin Heroin is a highly addictive opiate (like morphine). Brain cells can become dependent (highly addictive) on this drug to the extent that users need it in order to function in their daily routine. While heroin use starts out with a rush of pleasure, it leaves the use in a fog for many hours afterwards. Users soon find that their sole purpose in life is to have more of the drug that their body has become dependant on. From Dakota State University, a great resource on the effects of various drugs on the body and brain. See also, National Institute on Drug Abuse facts about heroin. Marijuana The parts of the brain that control emotions, memory, and judgment are affected by marijuana.  Smoking it can not only weaken short-term memory, but can block information from making it into long term memory. It has also been shown to weaken problem solving ability. Cannabis and Cognitive Functioning, Nadia Solowi, Cambridge Univ. Press, 1998. Alcohol Alcohol is no safer than drugs. Alcohol impairs judgment and leads to memory lapses. It can lead to blackouts. It distorts vision, shortens coordination, and in addition to the brain can damage every other organ in the body. Cocaine Cocaine, both in powder form and as crack, is an extremely addictive stimulant. An addict usually loses interest in many areas of life, including school, sports, family, and friends. Use of cocaine can lead to feelings of paranoia and anxiety. Although often used to enhance sex drive, physical effect of cocaine on the receptors in the brain reduce the ability to feel pleasure (which in turn causes the dependency on the drug). Cocaine: Effects on the Developing Brain, (Annals of the New York Academy of Sciences), John A. Harvey and Barry E. Kosofsky, Eds., New York Academy of Sciences, 1998. The Neurobiology of Cocaine Addiction: From Bench to Bedside, Herman Joseph and Barry Stimmel, Eds., Haworth Press, 1997. See National Institute on Drug Abuse facts about cocaine and crack. Inhalants Inhalants, such as glue, gasoline, hair spray, and paint thinner, are sniffed. The effect on the brain is almost immediate. And while some vapors leave the body quickly, others will remain for a long time. The fatty tissues protecting the nerve cells in the brain are destroyed by inhalant vapors. This slows down or even stops neural transmissions. Effects of inhalants include diminished ability to learn, remember, and solve problems.  See National Institute on Drug Abuse facts about inhalants. Ecstasy Extended use of this amphetamine causes difficulty differentiating reality and fantasy, and causes problems concentrating. Studies have found that ecstasy destroys certain cells in the brain.  While the cells may re-connect after discontinued use of the drug, they don't re-connect normally. Like most drugs, this one impairs memory and can cause paranoia, anxiety, and confusion. See National Institute on Drug Abuse facts about ecstasy. LSD While some people use LSD for the sense of enhanced and vivid sensory experience, it can cause paranoia, confusion, anxiety, and panic attacks. Like Ecstasy, the user often blurs reality and fantasy, and has a distorted view of time and distance. See National Institute on Drug Abuse facts about LSD. Steroids Anabolic steroids are used to improve athletic performance and gain muscle bulk. Unfortunately, steroids cause moodiness and can permanently impair learning and memory abilities. See National Institute on Drug Abuse facts about steroids. Tobacco Tobacco is a dangerous drug, putting nicotine into your body. Nicotine affects the brain quickly, like other inhalants, producing feelings of pleasure, like cocaine, and is highly addictive, like heroin. See National Institute on Drug Abuse facts about nicotine. Methamphetamine Known on the street as meth, speed, chalk, ice, crystal, and glass, methamphetamine is an addictive stimulant that strongly activates certain systems in the brain.  See National Institute on Drug Abuse facts about methamphetamine. Ritalin This drug is often prescribed to treat attention deficit disorder. It is becoming an illicit street drug as well. Drug users looking for a high will crush Ritalin into a powder and snort it like cocaine, or inject it like heroin. It then has a much more powerful effect on the body. It causes severe headaches, anxiety, paranoia, and delusions. The Amazing Brain

 

The Neurobehavioral Challenge

Four pounds and several thousand miles of interconnected nerve cells (about 100 billion) control every movement, thought, sensation, and emotion that comprise the human experience. Within the brain and spinal cord there are ten thousand distinct varieties of neurons, trillions of supportive cells, a few more trillion synaptic connections, a hundred known chemical regulating agents, miles of minuscule blood vessels, axons ranging from a few microns to well over a foot and a half in length, and untold mysteries of how—almost flawlessly—all these components work together. This is the amazing brain. 

Exploring the brain's anatomy, functional architecture, and neurofunctional systems provides the foundation for appreciating the neurobehavioral basis of ordinary daily functioning, creative processes, expression of talents, adjusting to brain injury, and psychopathology.

Functional Neuroanatomy Resources

"Indeed, perhaps the most important general observation that can be made about the brain is that its anatomy is the most important thing about it." --Gerald M. Edelman (Building a Picture of the Brain,
The Brain, G. M. Edelman and J.-P. Changeux, editors, Transaction Publishers, 2001) 

It is impossible to understand human behavior without some level of understanding of the physical structure--the brain--that enables behavior. While a sense of the molar (general or large-scale) structure is essential for a basic recognition of the master organ of the body, an appreciation of the molecular (denser, inner-intricacies) provides foundation and insight to the complex nuances of human behavior.

Functional neuroanatomy is the field that concerns itself with linking function with brain structure, sometimes referred to as behavioral neuroanatomy.  

Here are some excellent printed resources for exploring functional neuroanatomy. 

Atlas of Functional Neuroanatomy, Walter J. Hendelman, CRC Press, 2000. A supberb, detailed atlas with accompanying CD-ROM with images.

Neuroanatomy: A Functional Atlas of Parts and Pathways, Ray Poritsky, Hanley & Belfus, 1992. A coloring book approach with mostly 2D drawings but some good 3D drawings, too.

Neuroanatomy Made Easy and Understandable, Michael Liebman, Aspen, 1986. The basics with atlas of drawings and CT images.

Functional Neuroanatomy, Adel K. Afifi and Ronald A. Bergman, McGraw-Hill, 1998. Goes well beyond neuroanatomy to include extensive text descriptions of systems and pathways and the functional and clinical associations. Contains and extensive atlas of lateral, sagittal, and coronal sections through preserved specimens as well as MRI images.

Functional Systems: 3D Reconstructions with Correlated Neuroimaging, Hans-Joachim Kretschmann and Wolfgang Weinrich, Thieme, 1998. An excellent collection of computer-rendered, three-dimensional color pictures of brain systems. Provides an excellent way to visualize the spatial relations on brain systems. Expensive but worth it.

Neuroscience: Fundamentals for Rehabilitation, Laurie Lundy-Ekman, Saunders, 1998. An excellent, colorful neuroanatomy text with extensive relevant text for understanding clinical abnormalities and treatment applications.

"Behavioral Neuroanatomy" by M. -Marsel Mesulam in Principles of Behavioral and Cognitive Neurology, 2nd Edition, by M.-Marsel Mesulam, Oxford University Press, 2000.

Brain Maps

The study of brain anatomy reveals incredible complexity. The Brain Maps below provide schematic diagrams of the organization and pathways of major brain divisions that may help in learning functional neuroanatomy. These maps are in Adobe Acrobat format and may be printed for personal use. (All maps print in portrait orientation except for the main Brain Map: Major Divisions and Pathways, which prints in Landscape orientation.) The maps can be used alongside brain models and anatomical drawings to help understand the relationships among anatomical systems. The Maps may not be used for commercial use without permission. 

Brain Rehabilitation

Rehabilitation of brain functions involves two essential processes:  restoration of functions that can be restored and learning how to do things differently when functions cannot be restored to pre-injury level. The direction and methods of brain rehabilitation typically is defined by the neuropsychological symptoms identified following brain injury.  While practice in various cognitive tasks--doing arithmetic problems, solving logic puzzles, practicing concentration skills, or reading--may help brain rehabilitation, this is usually not enough.  Brain injury rehabilitation must be designed taking into account a broad range of neurofunctional strengths and weaknesses. Basic skills must be strengthened before more complex skills are added. Only through comprehensive neuropsychological analysis can the many possible effects of brain injury be sorted out. This pattern of functional strengths and weaknesses becomes the foundation for designing a program of brain rehabilitation. Brain recovery follows patterns of brain development. Gross or large-scale systems must develop (or be retrained) before fine systems. Attention, focus, and perceptual skills develop (or are retrained) before complex intellectual activity can be successful. Excellent print resources in brain injury rehabilitation include the following: Principles of Neuropsychological Rehabilitation by George P. Prigatano offers guiding principles clinicians can use to create an effective rehabilitation program. Mild Traumatic Brain Injury: A Therapy and Resource Manual by Betsy S. Green and others offers many resources for therapy professionals. Search "Brain Injury Rehabilitation" at www.amazon.com for additional resources Internet resources include the following: The National Institute of Health offers a consensus statement on Rehabilitation of Persons with Traumatic Brain Injury that is very comprehensive. It provides a thorough review of acceptable practices in treating persons with brain injury. The Traumatic Brain Injury Model Systems is a consortium of research and treating institutions. Their website offers a wealth of information about rehabilitation. The Brain Injury Association offers information, publications, and further links to resources about brain rehabilitation.  The Neuro-Developmental Treatment Association provides information about this therapeutic technique--known as NDT--that emphasizes rehabilitation that follows normal biological neurodevelopment. The Transitional Learning Center in Galveston has been a pioneer in brain injury rehabilitation since 1982. TLC provides survivors of brain injury with the special rehabilitation services needed to re-enter the community. TLC's website offers numerous informational resources.