Read Psychology for Dummies Online
Authors: Adam Cash
Tags: #Psychology, #General, #Body; Mind & Spirit, #Spirituality
Psychology for Dummies (9 page)
As you can see from preceding lists of brain divisions, there’s a whole lot going on. Essentially, everything we do involves our brains. What happens, though, when some part of the brain gets damaged? The behavior and mental processes associated with the damaged portion of the brain are adversely affected, which also has an impact on related functions. Clinical neuropsychologists are particularly interested in the behavioral and mental consequences of receiving a brain injury.
Our brains can be damaged in numerous ways:
Closed-head injuries:
These injuries occur when someone sustains a blow to the head without anything penetrating the skull. A common form of closed-head injury is a
contrecoup
injury — the injury occurs to the part of the brain opposite from where the individual was struck. If I’m hit in the back of the head, I may sustain damage to my frontal lobe, thus affecting my organizational and planning abilities.
Open-head injuries:
These injuries occur when the skull is either penetrated or fractured and can often lead to serious brain injury.
Other brain disorders:
Degenerative diseases such as Alzheimer’s can produce brain damage in the form of atrophied brain tissue and cellular death. Strokes and other vascular accidents also can result in brain damage by denying the brain blood and oxygen, causing cellular death.
The endocrine system is responsible for the hormonal functions of the body. You may have experienced the power of hormones in influencing behavior during those wonderful years we call puberty. We go to bed a boy or a girl; we wake up a maniac. Drastic changes in the balance of hormones can often have drastic effects on our behavior. So it goes for even minor changes such as the fluctuations of the menstrual cycle.
Specific glands throughout the body secrete hormones that influence our behavior and bodily functions. Ovaries and testes influence a great deal of sexual behavior. Sex hormones can influence when and how fast a child enters puberty, for example. Hormones secreted by the adrenal gland influence aggressive behavior. The pituitary gland plays a role in our stress levels.
The use of medications in the treatment of mental illness has gained prominence over the last 50 or so years. Hundreds of drugs have been developed that are used to target the specific symptoms of a particular mental disorder with amelioration of their expression, alleviation of suffering, and improvement of overall functioning as primary goals of
pharmacotherapy.
Many brain systems involved in the symptoms of mental illness involve one particular neurotransmitter. The sleep difficulties and appetite disturbance often seen in major depressive disorder are thought to be related to the limbic system for example. Drugs used for the treatment of mental illness are designed to affect the functioning of the specific neurotransmitters in that brain region. For these particular symptoms, the neurotransmitter serotonin is targeted.
Theoretically, different disorders, or more specifically, different symptoms implicate different neurotransmitters. Drugs designed to treat these symptoms are selective for their effects on the particular neurotransmitter involved.
Medications that are used to treat depression are called
antidepressants.
Most antidepressants affect one or both of two neurotransmitters:
norepinephrine
and
serotonin.
Basically, there are two different classes of antidepressant medications differentiated by their mechanism of action.
Tricyclic antidepressants,
for example, block the presynaptic neuron’s re-absorption of mostly norepinephrine (NE). This allows for a functional “increase” in the level of NE in the synapse and prolongs the activation of the postsynaptic neuron when stimulated by NE.
Selective serotonin reuptake inhibitors (SSRIs)
block the re-absorption of serotonin rather than NE and have the similar effect of prolonging activation. Some of the more popular brands of SSRIs are Prozac, Paxil, and Zoloft.
The experience of auditory hallucinations or feeling like someone is out to get you can be extremely troubling. These are common symptoms of the mental disorder schizophrenia. One of the most powerful treatments for some of the symptoms of schizophrenia is the use of
antipsychotic medications.
Antipsychotic medications have a specific effect on the neurotransmitter dopamine. The
dopamine dysregulation hypothesis
of schizophrenia holds that the symptoms of psychosis result from disruptions in the action of dopamine in the brain. Antipsychotic medications block the postsynaptic receptor sites of dopamine. This blockage keeps dopamine from being able to activate the postsynaptic neuron and has been found to reduce the presence of psychotic symptoms substantially.
Unfortunately for antipsychotic medications, as for all medications, they don’t just affect the neurotransmitters in the brain areas theorized to be implicated in the disorder. They also affect other brain areas and can often lead to very unpleasant side effects. The experience of these side effects often leads people to stop taking their medication, which can have serious negative consequences. This situation keeps drug researchers searching for more selective drugs.
Anxiety disorders are the most common mental disorder in the United States. Millions of people suffer from intolerable worry, panic attacks, and disabling phobias. The good news is that medications can help with these symptoms.
Anxiolytic medications
are drugs designed to relieve the symptoms of anxiety disorders. Psychiatrists and family physicians prescribe one class of anxiolytics,
benzodiazapines,
quite often. Benzodiazepines affect the neurotransmitter GABA, which has a suppressing effect on the central nervous system. In other words, it slows things down in the brain.
Benzodiazepines are very effective in reducing anxiety. Unfortunately they are also highly addictive. They have a near-immediate effect and often produce sedation and an overall feeling of calmness. These feelings are highly pleasurable, and patients sometimes don’t want to stop taking these medications even after their anxiety disorder has been successfully medicated. Table 3-1 gives an overview of some frequently prescribed medications.
Table 3-1: Major Medication Groups Medication Problem Common Example Antidepressants Depression Prozac Panic disorder Zoloft Obsessive-compulsive disorder Paxil Bulimia Social phobia Antianxiety/Anxiolytics Insomnia Benzodiazepines Situational anxiety Generalized anxiety disorder Panic disorder Antipsychotics Schizophrenia Haldol Mania Zyprexa Psychotic depression Mood stabilizers Mania Lithium Bipolar disorder Depakote Stimulants ADHD Ritalin
In This Chapter
Turning on the light
Breaking through to the other side
Going to bed
Traveling the royal road
P erhaps since the beginning of time, human beings have been trying to alter their consciousness. For some, it may seem like a way to get in touch with a reality greater than themselves. For others, it may simply be a way to escape the harsh realities of a bad home or a meaningless job. Wallace and Goldstein defined
consciousness
as our current state of awareness of external and internal stimuli. A
stimulus
is anything in our world (an event, situation, or object) that triggers a psychological response.
Being conscious is like having a light on in our brain. When the light is out, we’re unconscious. Consciousness allows us to monitor ourselves and our environment, giving us greater control over our actions and behaviors. But, if you’ve stood on a busy street corner in a large city, you’ve realized that there’s a heck of a lot going on around us at any given time. We only have so much awareness to go around. Consciousness has its limits. The quantity or amount of material in our awareness, along with the content of that material, defines the level of consciousness we find ourselves in at any one moment.
