Psychology related things.
medicalschool:

Cerebral angiography is a procedure that uses a special dye (contrast material) and x-rays to see how blood flows through the brain. For a cerebral arteriogram, arterial access is usually obtained in the femoral artery in the groin. Once the catheter is inserted, the contrast dye is injected, and a series of X-ray pictures is made. These X-ray images show the arterial, venous, and capillary blood vessel structures and blood flow in the brain.
A cerebral arteriogram may be performed to detect abnormalities of the blood vessels within or leading to the brain. Such abnormalities include aneurysms, stenosis, arteriovenous malformation (a condition in which there is an abnormal connection between the arteries and veins), thrombosis (a blood clot within a blood vessel), vasospasm (a spasm of the blood vessel causing an irregular narrowing of the vessel), or occlusion (complete obstruction of a blood vessel). Other conditions that cause a displacement of the brain’s blood vessels may be detected by a cerebral arteriogram. These conditions include tumors, edema (swelling), herniation (dislocation of the brain tissue, caused by pressure within the brain due to swelling, bleeding, or other reasons), increased intracranial pressure (ICP, or increased pressure within the brain), and hydrocephalus (fluid in the brain).

medicalschool:

Cerebral angiography is a procedure that uses a special dye (contrast material) and x-rays to see how blood flows through the brain. For a cerebral arteriogram, arterial access is usually obtained in the femoral artery in the groin. Once the catheter is inserted, the contrast dye is injected, and a series of X-ray pictures is made. These X-ray images show the arterial, venous, and capillary blood vessel structures and blood flow in the brain.

A cerebral arteriogram may be performed to detect abnormalities of the blood vessels within or leading to the brain. Such abnormalities include aneurysms, stenosis, arteriovenous malformation (a condition in which there is an abnormal connection between the arteries and veins), thrombosis (a blood clot within a blood vessel), vasospasm (a spasm of the blood vessel causing an irregular narrowing of the vessel), or occlusion (complete obstruction of a blood vessel). Other conditions that cause a displacement of the brain’s blood vessels may be detected by a cerebral arteriogram. These conditions include tumors, edema (swelling), herniation (dislocation of the brain tissue, caused by pressure within the brain due to swelling, bleeding, or other reasons), increased intracranial pressure (ICP, or increased pressure within the brain), and hydrocephalus (fluid in the brain).

Monday, 15 July 2013

Human Beings Are Information Processors

Schema theory defines cognitive schemas as mental representations of knowledge. Mental representations are stories in categories in memory. These schemas provide guidelines for interpretation of incoming information when people try to make sense of the world. Schemas influence cognitions in that schemas create expectations about what will happen in specific situations. Schema theory can, to a large extent, explain reconstructive memory and stereotyping.

Darley and Gross (1983) performed an experiment in which they showed participants videos of a girl playing in a poor environment, then in a wealthy environment. Then they saw a video of the girl in what could be an intelligence test. When the participants were asked to judge the future of the girl they all said that the “poor” girl would do worse than the “wealthy” girl. The study demonstrated how human beings actively process information based on a few salient details to form an overall impression that may not necessarily be correct. 

 

Friday, 12 July 2013

Digital Textbooks vs Traditional Textbooks

In our high school, we’ve been given the option of whether we would like to have a physical or a digital copy of the class textbook. Despite the advantages of digital textbooks, I made the decision of receiving traditional textbooks instead for various reasons. For my particular school, the online option consists of being given a lengthy numerical and alphabetical passcode that needs to be entered in order to access the textbook. Despite the obvious problem of losing or failing to commit the passkey to memory, there also exists the problem of Internet access. Digital textbooks pose a great disadvantage for the students who lack decent or any Internet access. For example, I did choose to have the digital textbook for one of my classes and found that the system would often crash if my Internet access weren’t at full speed to load the desired pages. In addition, the traditional textbooks offer you the constructive option of posting an abundance of post-it notes upon the pages. Yet there still exists the problem of students losing or damaging their textbooks, which is a reason why I believe that the digitalization of textbooks will become both more beneficial and environmentally friendly in the future. However, I believe that the software should be altered to allow the books to be in a pdf format to avoid the necessity of Internet access and allow access to all students.

Thursday, 11 July 2013

Ancient Views and Treatments - Trephination

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People in prehistoric societies apparently believed that all events around and within them resulted from the actions of magical, sometimes sinister, beings who controlled the world. In particular, they viewed the human body and mind as a battleground between external forces of good and evil. Abnormal behavior was typically interpreted as a victory by evil spirits, and the cute for such behavior was to force the demons from a victim’s body.

This supernatural view of abnormality may have begun as far back as the Stone Age. Some skulls from that period recovered in Europe and South America show evidence of an operation called trephination, in which a stone instrument, or trephine, was used to cut away a circular section of the skull. Some historians have concluded that this early operation was performed as a treatment for severe abnormal behavior – either hallucinations or melancholia. The purpose of opening the skull was to release the evil spirits that were supposedly causing the problem.  

Electroencephalogram (EEG)

The electroencephalogram (EEG) is based on electrical recordings taken from the scalp. It was first used by Hans Berger over 65 years ago. Electrodes placed on the scalp pick up very small changes in electrical activity within the brain. These changes are shown on a computer screen and can also be printed out. The pattern of changes is sometimes referred to as “brain waves”.

The EEG has proved useful in many ways. For example, it has been found that there are five stages of sleep, varying in terms of the depth of sleep and the presence or absence of dream activity. These stages differ in terms of the EEG record, and EEG research was crucial in identifying these stages. It has also proved useful in the detection of epilepsy, damaged brain tissue, and the location of tumors by abnormal changes in brain wave patterns. 

The EEG has further been of value in identifying the functions of the two hemispheres of the brain. There is more activity in the left hemisphere than in the right hemisphere when someone is carrying out a language-based task. However, the opposite is the case during the performance of a spatial task. 

However, there are also various limitations to the use of the EEG, such as the fact that it measures electrical activity in several areas of the brain at once, and so it is hard to work out which parts of the brain are more active, and which are less active. It is also an indirect measure of brain activity because the recording electrodes are on the scalp. The EEG has been compared to trying to hear what people are saying in the next room by putting your ear to the wall. 

Friday, 5 July 2013

Effects of Neurotransmission on Human Behavior

Neurotransmitters are the chemical substances that receive information from other neurons through their dendrites and transmit it by electrical impulse across the cell body and along the axon to the terminal buttons at the end. The communication between the two neurons occurs in the synapse between two neurons. They are the building blocks of behavior.

The neurons send electrochemical messages to the brain so people can respond to stimuli from either the environment or internal changes in the body.

Neurotransmitters have a range of different effects on human behavior. They trigger behaviors such as mood, memory, sexual arousal, and mental illness. Two examples are the neurotransmitters serotonin and dopamine. Serotonin effects sleep, emotion, and arousal levels while dopamine effects learning, voluntary movement and feelings of pleasure. There are certain drugs that can help reduce or increase the transmission of certain neurons.

Neurons are specific in which neurotransmitters they can release and often, neurons working with certain neurotransmitters can be found in greater or lesser concentration. This means that at times, the amount of neurons that get sent around the body can be too much or too little; therefore, drugs are used to be able to regulate the amount of neurotransmission that should be happening within a person’s body. For example, a drug called Prozac prevents the re-uptake of serotonin in the brain, which allows for more successful regulation of mood. People who suffer from depression use this drug to help improve their moods. 

Sunday, 17 February 2013

Cyclothymia

Cyclothymia is a mild form of bipolar disorder. It is characterized by mood fluctuations that shift between depressive and hypomanic phases. Cyclothymics do not experience the extremes of major depression or manic episodes.

The depressive or hypomania symptoms of cyclothymia may last for a few days to several weeks at a time, with brief intervals of normal mood in between. Personality changes are often evident to family and friends. Individuals who have a stable mood for longer than two months at a time are not likely cyclothymic. Symptoms may be mimicked by substance abuse, borderline personality disorder, or other mood disorder. A family history of depressive or bipolar disorders increases the risk.

Symptoms of Cyclothymia

Hypomanic Phase

  • Excessive confidence and self-esteem
  • Reduced ability to concentrate, easily distracted
  • Sleep difficulties, excessive energy
  • Heightened irritability
  • Reduced inhibitions, may make foolish decisions
  • Hypomania lasts between several days and several weeks

Depressive Phase

  • Feelings of inadequacy, low self-confidence
  • Difficulty falling asleep, unrestful sleep
  • Fatigue, lack of energy
  • Negative thinking, feelings of guilt and sadness
  • Loss of interest in formerly enjoyable activities
  • Depression lasting between several days and several weeks

The cycling between phases must be present for at least two years for a diagnosis (one year for teenagers). Work and family life are often negatively affected by the shifting moods.

Differences by Gender and Age

Cyclothymia, like the related bipolar disorder, affects men and women in roughly equal numbers. The disorder typically begins in the teenage or young adult years. Onset later in life is rare, and may be brought on by substance abuse or certain medications. Cyclothymia may progress to bipolar, though treatment may prevent this.

Sunday, 10 February 2013

Normopathy

Psychiatric theorist Christopher Bollas invented the idea of normopathy to describe people who are so focused on blending in and conforming to social norms that it becomes a kind of mania. A person who is normotic is often unhealthily fixated on having no personality at all, and only doing exactly what is expected by society. Extreme normopathy is punctuated by breaks from the norm, where normotic person cracks under the pressure of conforming and becomes violent or does something very dangerous. Many people experience mild normopathy at different times in their lives, especially when trying to fit into a new social situation, or when trying to hide behaviors they believe other people would condemn.

Sunday, 20 January 2013
Monday, 7 January 2013

Positive Effects of Depression

Sadness, apathy, preoccupation. These traits come to mind when people think about depression, the world’s most frequently diagnosed mental disorder. Yet, forthcoming research in the Journal of Abnormal Psychology provides evidence that depression has a positive side-effect. According to a new study, depressed individuals perform better than their non-depressed peers in sequential decision tasks.

In their study, participants — who were healthy, clinically depressed, or recovering from depression — played a computer game in which they could earn money by hiring an applicant in a simulated job search. The game assigned each applicant a monetary value and presented applicants one-at-a-time in random order. Experiment participants faced the challenge of determining when to halt search and select the current applicant. In addition to resembling everyday decision problems, such as house shopping and dating, the task has a known optimal strategy. As reported, depressed patients approximated this optimal strategy more closely than non-depressed participants did. While healthy participants searched through relatively few candidates before selecting an applicant, depressed participants searched more thoroughly and made choices that resulted in higher payoffs.

This discovery provides the first evidence that clinical depression may carry some benefits. For decades, psychologists have debated whether depression has positive side-effects. While researchers have recognized that most symptoms of depression impede cognitive functioning, scholars such as Paul Andrews of the Virginia Institute for Psychiatric and Behavioral Genetics and Andy Thomson of the University of Virginia have proposed that depression may promote analytical reasoning and persistence — that is, qualities useful in complex tasks.

 
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