Monday, July 28, 2008

Brain electrodes tackle severe depression

Severely depressed patients who do not respond to conventional therapy may be helped by deep brain stimulation (DBS), according to the most-extensive study to date of the experimental procedure.

In a clinical trial in Toronto, Canada, 12 out of 20 patients who had stimulating electrodes placed in a brain area called the subcallosal cingulated gyrus showed significant improvement in their depression, with seven of them going into full remission.

source : http://www.nature.com

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Monday, July 21, 2008

Eyewitnesses May Misidentify Perpetrator Of A Crime Due To Stress Or Fear

A study about the fragility of eyewitness identification used within the criminal justice system, has conducted by researchers at Goldsmiths, University of London. According to this study, stress and fear reduce the likelihood of successful identification, bringing into question a victim’s ability to identify the perpetrator of a crime.

Visitors to the London Dungeon were asked to describe and identify an actor encountered in the ‘Labyrinth of the Lost’ who stepped out to block their path. Whilst they were in the labyrinth, some participants wore a heart rate monitor to measure the level of their anxiety.

The researchers found that participants who had experienced a higher state of anxiety were less likely to report correct descriptions of the actor and were less likely to correctly identify him/her in a line-up than participants who had experienced less anxiety.

Most research on the effectiveness of eyewitness identification is likely to overestimate accuracy because the participant witnesses do not feel the fear or stress evoked by crime that would be present in real situations.

For ethical reasons, participants in experiments cannot be subjected to the same stress that a victim of crime may experience. This study sought to recreate a similar level of fear and stress, however, by using the scare in the London Dungeon so as to understand what effect such stress may have on memory.

Professor of Psychology, Tim Valentine, who headed the research, emphasised the significance of the results: “We know already that mistaken eyewitness identification is the leading cause of wrongful convictions in the USA. This research takes us a step closer to understanding the problem.”

“The experience in the Labyrinth of the Lost is much less extreme than the stress a victim of crime may experience, but we still observed a catastrophic failure of identification by visitors who found the experience stressful.”

“The research doesn’t suggest there is anything wrong with the identification procedures that the police use, but does demonstrate just how difficult it can be for a victim to identify the offender.”

Evidence shows that mistaken eyewitness identification is a common cause of miscarriages of justice. 218 people wrongly convicted in the USA have been exonerated by new DNA analysis from crime scene samples. 75% of these cases were the result of mistaken eyewitness identification.

source: http://www.sciencedaily.com

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Tuesday, July 15, 2008

Culture And Depression - New Data May Help Doctors More Accurately Diagnose Patients

The expectation that East-Asian people emphasize physical symptoms of depression (e.g. headaches, poor appetite or aches/pains in the body) is widely acknowledged, yet the few available empirical studies report mixed data on this issue. A new study from the Centre for Addiction and Mental Health (CAMH) debunks this cultural myth, and offers clinicians valuable insight to into cultural context when assessing a patient, leading to more accurate diagnosis.

Lead by CAMH Clinical Research Director Dr. R. Michael Bagby, in collaboration with Dr. Andrew Ryder, Concordia University, Steven Heine, University of British Columbia and a number of collaborators from Second Xiangya Hospital of Central South University, People’s Republic of China, this study recruited more than 200 participants, half from an outpatient clinic in China, and half from a clinical research department outpatient clinic at CAMH, and tested two central hypotheses: 1. East-Asian participants will emphasize somatic or physical symptoms of depression more than North American participants, and 2. North American participants would emphasize psychological symptoms of depression (e.g. report feeling sad, crying spells, or a loss of self-confidence) more than East-Asian participants. Dr. Bagby and his team also wanted to examine the role stigma and alexithymia (difficulty using words to describe emotions) play in how each culture presented and expressed depression symptoms.

This rigorous work is one of only a few studies to address these questions with a direct cross-cultural comparison of clinical patients. Also, it is the only study to use three assessment tools (spontaneous report of problems during unstructured discussion with doctor; clinician-rated symptoms in a structured clinical interview; and a symptom rating scale in questionnaire form) translated into both English and Chinese (Mandarin) and modified to address cross-cultural differences.

As Dr. Bagby explains, “the onset of depression triggers a biological response that takes place within a specific social context, resulting in a cascade of somatic and psychological experiences that are interpreted through a particular cultural lens. Careful translation and adaptation of our assessment tools helped us clarify if different approaches lead to different symptom profiles and conclusions about patients.”

Overall, the data demonstrate a consistently greater level of psychological symptom reporting in the North American sample, regardless of assessment tool. This suggests a tendency for Western cultures to emphasize psychological symptoms of depression (psychologization), rather than a tendency for those from East-Asian cultures to emphasize physical symptoms (somatization).

East-Asian participants did report a significantly higher level of somatic symptoms when reporting through the spontaneous interview and structured clinical interview. Also, these participants reported higher levels of stigma and alexithymia. A refined examination of this link revealed that the observed cross-cultural differences in somatic symptom scores relates, in part, to cultural differences in internally versus externally oriented thinking. This suggests that people who do not frequently focus on their internal emotional state are more likely to notice somatic symptoms.

While this data may help clinicians be more aware of how culture can impact how people talk about their illness, this data does not constitute a norm for depression worldwide. More work should be done to understand the interaction of biology, culture and individual differences in predicting variations in how people present symptoms of depression.

The Centre for Addiction and Mental Health (CAMH) is Canada’s largest mental health and addiction teaching hospital, as well as one of the world’s leading research centres in the area of addiction and mental health. CAMH combines clinical care, research, education, policy development and health promotion to transform the lives of people affected by mental health and addiction issues.

CAMH is fully affiliated with the University of Toronto, and is a Pan American Health Organization/World Health Organization Collaborating Centre.

source: http://www.medicalnewstoday.com

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Thursday, July 3, 2008

Depression Ups Risk Of Complications Following Heart Attack

People who suffer from severe depression following a heart attack might be more likely to experience cardiac complications while hospitalized, according to a new study.

Lead author Jeff Huffman, M.D., and assistant professor of psychiatry at Harvard Medical School said,”There is good evidence that if a person has depression after a heart attack, they are more likely to die from cardiac causes in the following months and years. But it can not studied yet whether depression impacts cardiac outcomes immediately after a heart attack-the time we see the most complications.”

There are 129 patients included in the study at Massachusetts General Hospital. Within 72 hours of having a heart attack, each participant underwent an interview to determine if he or she suffered from depression or not. 17 of the original group members had a diagnosis of major depression lasting for at least two weeks.

Major depression was a significant predictor of heart rhythm problems, congestive heart failure or a second heart attack.

Huffman added,”The results suggest that physicians should be especially mindful of treating depression in patients with cardiac risk factors, and also suggest close in-hospital monitoring of heart attack patients with major depression given this increased risk for complications.”

David Bush, M.D., associate professor at The Johns Hopkins University School of Medicine and Heart Institute said,”Surprising thing is that differences in outcomes were seen in a relatively short time and the new observation is that risk for these bad outcomes start while patients are still in the hospital”.

Posted by Tom at 10:01:09 | Permalink | No Comments »