January 13, 2011

“Erasing” Traumatic Memories Moving from Science Fiction to Scientific Reality

From: TheGlobeandMail.com

The brain has a remarkable capacity for keeping track of our past experiences. But detailed memories can sometimes seem more a curse than a blessing. This is especially true for those who’ve suffered significant losses or other traumas. Thus, while the holiday season is meant to be a joyous time, for many it merely provides salient reminders of these debilitating experiences.

Fortunately, researchers are discovering that memories may be far less durable than previously thought. Indeed research on “erasing” traumatic memories is quickly moving from the realm of science fiction to scientifically backed reality.

That each of us may be able to exert some control over what gets in and what then stays in long-term memory arises from our growing understanding of how the brain represents and stores information related to our conscious life experiences.

Read the entire article: “Erasing” Traumatic Memories Moving from Science Fiction to Scientific Reality

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October 25, 2010

Seizing an Opportunity: Broader Definitions of Epilepsy May Lead to Better Treatments

From The Dana Foundation:

There is not just one type of epilepsy. While some forms of the disease are characterized by convulsive seizures, others involve seizures that are barely noticeable. Seizures can occur for many reasons: they can be caused by genetic mutations, injury, or infection early in life. In addition, events in daily life, such as stress, or normal variations in hormones, such as estrogen and testosterone, can influence brain activity and therefore influence seizures. By considering the powerful interactions between the brain and the endocrine system, this influence of hormones on seizures can be understood and new treatment options can be considered.

A common misconception is that a seizure involves sudden, uncontrolled movements or convulsions. However, convulsions do not always accompany seizures. One type of epilepsy—absence epilepsy—is characterized by seizures that involve little movement at all, only a blank, expressionless gaze. For a brief period, the person experiencing the seizure is unresponsive, or “absent.” These seizures are not easy to recognize and may therefore go undetected. Even the person having the seizure may not notice it, because consciousness is temporarily interrupted during an absence seizure.

The diversity in the types of seizures has led to difficulty in classifying them. It is often hard to bring seizures under control because there are many causes, some of which are not well understood. Fortunately, in the past few decades clinical and laboratory research has led to a better understanding of the diversity of seizures and the causes of epilepsy.

Click here to read the entire article

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October 22, 2010

What research paradigms have cognitive psychologists used to study “False memory,” and what are the implications of these choices?

K. Pezdek, S. Lam
Article in Consciousness and Cognition

This research examines the methodologies employed by cognitive psychologists to study “false memory“, and assesses if these methodologies are likely to facilitate scientific progress or perhaps constrain the conclusions reached. A PsycINFO search of the empirical publications in cognitive psychology was conducted through January, 2004, using the subject heading, “false memory.” The search produced 198 articles. Although there is an apparent false memory research bandwagon in cognitive psychology, with increasing numbers of studies published on this topic over the past decade, few researchers (only 13.1% of the articles) have studied false memory as the term was originally intended—to specifically refer to planting memory for an entirely new event that was never experienced in an individual’s lifetime. Cognitive psychologists interested in conducting research relevant to assessing the authenticity of memories for child sexual abuse should consider the generalizability of their research to the planting of entirely new events in memory.

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October 21, 2010

Could an Experimental Memory Drug Put an End to “Senior Moments”?

From: Discover Magazine Online:

A new drug seems to be able to reverse normal age-related memory decline in old mice–like a face-lift for neurons, bringing them back to their younger days. The results of the experimental treatment, which works by blocking certain stress hormones, were published in the Journal of Neuroscience.

“What’s most surprising is that even short-term inhibition was able to reverse memory loss in old mice,” says Jonathan Seckl, a professor of molecular medicine who was involved in the research. “I don’t think people had realized this was so reversible. It takes [the animals] back to being relatively young.” [Technology Review].

Research has shown that stress hormones called glucocorticoids play a role in memory loss, by damaging the brain over time. But targeting the glucocorticoids themselves is dangerous, because reducing their levels would leave the body without a stress response. The researchers therefore targeted an enzyme instead, which activates the hormone in neurons.

Click here for the complete article.

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March 5, 2008

Gene variants may increase risk of anxiety disorders

anx.jpegFrom physorg: Massachusetts General Hospital (MGH) researchers – in collaboration with scientists at the University of California at San Diego and Yale University – have discovered perhaps the strongest evidence yet linking variation in a particular gene with anxiety-related traits. In the March issue of Archives of General Psychiatry, the team describes finding that particular versions of a gene that affects the activity of important neurotransmitter receptors were more common in both children and adults assessed as being inhibited or introverted and also were associated with increased activity of brain regions involved in emotional processing.

“We found that variations in this gene were associated with shy, inhibited behavior in children, introverted personality in adults and the reactivity of brain regions involved in processing fear and anxiety,” says Jordan Smoller, MD, ScD, of the MGH Department of Psychiatry, the report’s lead author. “Each of these traits appears to be a risk factor for social anxiety disorder, the most common type of anxiety disorder in the U.S.”

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January 9, 2008

Cheap drugs against aggression don’t work

Study shows placebos as good as antipsychotics for the intellectually disabled.

Scientists have discovered that taking a sugar pill is more effective than routine medications in treating aggression in people with intellectual disabilities. Until now, patients with intellectual disabilities have been prescribed antipsychotic drugs — normally given to people with a psychiatric disease like schizophrenia — to treat aggressive behaviour such as head banging. But evidence for the drugs’ effectiveness has been thin.

“Antipsychotic drugs are widely used because they are cheap and at high doses they sedate people,” says Eric Emerson at Lancaster University, an expert in the behaviour of intellectually disabled people.

Peter Tyrer, based at Imperial College London, led an international research project looking at 86 people with intellectual disability at clinics across England, Wales and at one centre in Australia. Patients being treated for aggressive behaviour randomly received one of two antipsychotic drugs — respiridone or haloperidol — or a placebo.

Nature News

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January 4, 2008

Altered emotional response in bipolar mania

abnormal states,neuroimaging,psychiatry — thomasr @ 11:20 am

Psychiatric illnesses are often good models for testing the functional relationship between specific regions of the brain. At the same time, one may gain insight into the neurocognitive mechanisms behind a specific disease.

This is the case in a recently published study in Psychiatry Research by Foland et al.:

Evidence for deficient modulation of amygdala response by prefrontal cortex in bipolar mania.
Foland LC, Altshuler LL, Bookheimer SY, Eisenberger N, Townsend J, Thompson PM.

Several studies have implicated the involvement of two major components of emotion regulatory networks, the ventrolateral prefrontal cortex (VLPFC) and amygdala, in the pathophysiology of bipolar disorder. In healthy subjects, the VLPFC has been shown to negatively modulate amygdala response when subjects cognitively evaluate an emotional face by identifying and labeling the emotion it expresses.

The current study used such a paradigm to assess whether the strength of this modulation was altered in bipolar subjects when manic. During functional magnetic resonance imaging (fMRI), nine manic subjects with bipolar I disorder and nine healthy subjects either named the emotion shown in a face by identifying one of two words that correctly expressed the emotion (emotion labeling task) or matched the emotion shown in a face to one of two other faces (emotion perception task). The degree to which the VLPFC regulated amygdala response during these tasks was assessed using a psychophysiological interaction (PPI) analysis.

Compared with healthy subjects, manic patients had a significantly reduced VLPFC regulation of amygdala response during the emotion labeling task. These findings, taken in context with previous fMRI studies of bipolar mania, suggest that reductions in inhibitory frontal activity in these patients may lead to an increased reactivity of the amygdala.

Psychiatry Res. 2008 Jan 15;162(1):27-37.

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October 18, 2007

How Schizophrenia Develops: Major Clues Discovered

schizo.jpegSchizophrenia may occur, in part, because of a problem in an intermittent on/off switch for a gene involved in making a key chemical messenger in the brain, scientists have found in a study of human brain tissue. The researchers found that the gene is turned on at increasingly high rates during normal development of the prefrontal cortex, the part of the brain involved in higher functions like thinking and decision-making — but that this normal increase may not occur in people with schizophrenia.

The gene, GAD1, makes an enzyme essential for production of the chemical messenger, called GABA. The more the gene is turned on, the more GABA synthesis can occur, under normal circumstances. GABA helps regulate the flow of electrical traffic that enables brain cells to communicate with each other. It is among the major neurotransmitters in the brain.

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September 6, 2007

New insights into OCD

abnormal psych,personality,psychiatry — thomasr @ 3:48 pm

ocd.jpegObsessive-compulsive disorder (OCD) is a common debilitating psychiatric disorder, yet the cause of OCD is unknown and few effective treatments are available. A recent study of mutant mice reveals a novel mechanism leading to OCD-like behaviors in mice and suggests potential new therapeutic strategies.

By Dr. Jing Lu and Dr. Guoping Feng, in Scitizen.com

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September 3, 2007

Psychiatrists the least religious

human nature,naturalism,psychiatry — thomasr @ 3:30 am

In a recent survey of American physicians (see also here) it was found that the least religious of all medical specialties is psychiatry. It was also found that religious physicians, especially Protestants, are less likely to refer patients to psychiatrists, and more likely to send them to members of the clergy or religious counselors. As co-author Farr Curlin claims:

“Something about psychiatry, perhaps its historical ties to psychoanalysis and the anti-religious views of the early analysts such as Sigmund Freud, seems to dissuade religious medical students from choosing to specialize in this field,”

scr_logo.jpgSCR comment: Another possibility is that psychiatrist, contrary to other medical specialities, see the direct consequences of how both therapeutic (as well as recreational) drugs can alter the mind. It would be interesting to know whether the runner-up on the atheist scoreboard is the group of neurologists. This could suggest that these groups are more likely to view the mind as a product of the brain, and that other medical specialist groups may still operate (e.g. implicitly) with a view that allows a distinction between a physical body and a non-physical mind.

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August 26, 2007

When the Need to Belong Goes Wrong

socialphobia.jpegWhen the Need to Belong Goes Wrong: The Expression of Social Anhedonia and Social Anxiety in Daily Life

People possess an innate need to belong that drives social interactions. Aberrations in the need to belong, such as social anhedonia and social anxiety, provide a point of entry for examining this need. The current study used experience-sampling methodology to explore deviations in the need to belong in the daily lives of 245 undergraduates. Eight times daily for a week, personal digital assistants signaled subjects to complete questionnaires regarding affect, thoughts, and behaviors.

As predicted, higher levels of social anhedonia were associated with increased time alone, greater preference for solitude, and lower positive affect. Higher social anxiety, in contrast, was associated with higher negative affect and was not associated with increased time alone. Furthermore, greater social anxiety was associated with greater self-consciousness and preference to be alone while interacting with unfamiliar people.

Thus, deviations in the need to belong affect social functioning differently depending on whether this need is absent or thwarted.

Psychologial Science

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August 2, 2007

Trating panic disorders — an update

abnormal psych,psychiatry — thomasr @ 4:34 am

Psychotherapy and benzodiazepines have been reported as effective panic disorder treatments individually with different benefits and disadvantages. Does combining the therapies offer extra advantages? Medscap.com brings a report.

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May 24, 2007

Visual hallucinations? Draw it!

epilepsy_brain.jpgVisual (and other non-visual) hallucinations sometimes occur during epileptic seizures. A relatively straightforward but little used method to describe these experiences is to ask the sufferer to draw the hallucinations — even as they occur.

According to G.D. Schott, in an article in the latest issue of Brain, such descriptions not only not only serve as tools to understand the sufferer and symptoms; they can also be used for differential diagnosis. 

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March 7, 2007

Bipolar depression — treatment and perils

abnormal psych,psychiatry — thomasr @ 3:34 pm

Why is it seemingly more difficult to treat bipolar depression than bipolar mania? Why does it seem so hard to get the FDA to approve medications for bipolar depression? Medscape brings the latest news.

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December 22, 2006

Inducing a dreamy state

braineletrodes.jpgBrain stimulation provides an interesting tool to study the functions of a given area of the brain. In a study by Vignal et al. published in Brain, artificial stimulation or seizures in specific mesial temporal lobe structures were assessed both in terms of location and phenomenology.

Among the findings, the researchers found that “Forty-five per cent of dreamy states were evoked by stimulation of the amygdala, 37.5% by the hippocampus and 17.5% by the para-hippocampal gyrus.”

Furthermore, they found that their study “demonstrates the existence of large neural networks that produce recall of memories via activation of the hippocampus, amygdala and rhinal cortex.”

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November 19, 2006

Altered cognition and emotion in depersonalization disorder

depersonal.jpgDepersonalization Disorder (DPD) is a dissociative disorder in which sufferers are affected by persistent feelings of depersonalization. The symptoms include a sense of automation, feeling a disconnection from one’s body, and difficulty relating oneself to reality. In a recent study Medford et al. reports that patients with DPD do not process emotionally salient material in the same way as healthy controls, in accordance with their subjective descriptions of reduced or absent emotional responses

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