The risky business of dopamine agonists in Parkinson disease and impulse control disorders.

Claassen, D. O., van den Wildenberg, W. P. M., Ridderinkhof, K. R., Jessup, C. K., Harrison, M. B., Wooten, G. F., & Wylie, S. A. (2011). The risky business of dopamine agonists in Parkinson disease and impulse control disorders. Behavioral Neuroscience, 125(4), 492-500. doi:10.1037/a0023795

The second article I chose for chapter 16 was over the neurological disorder Parkinson’s disease. Although there has been a lot of research done over neurological and psychological disorders, studies are constantly evolving what we know about these disorders. Parkinson’s disease is related to the degeneration of the substantia nigra and loss of the neurotransmitter dopamine. Symptoms of Parkinson’s disease include tremor at rest, muscular rigidity, akathesia, disorders of posture, disorders of locomotion, slowness of movement, and disturbances of speech. This disorder could be caused by encephalitis, syphilis, and drugs. The title of the article I chose was “The risky business of dopamine agonists in Parkinson’s disease and impulse control disorders.” The researchers in this study said that in spite of potential negative consequences, risk taking behavior is described by the chase of a reward. The neurotransmission of dopamine in the mesocortilimbic pathway was found as a modulator of risk behavior. This study evaluated patients with Impulse control disorder and Parkinson’s disease. Impulse Control Disorder is characterized by hyper-sexuality, compulsive gambling, eating, and shopping. These compulsive behaviors are associated with risky behavior. These behaviors are also thought to be the result of dopaminergic medication. Researchers used the Balloon Analogue Risk Task to assess the how agonist therapy affected risk behaviors in Parkinson’s patients that were diagnosed with impulse control disorder and actively displayed symptoms. There were a total of 41 participants: 22 with ICD and 19 without ICD. Researchers asked the patients to perform the task both “on” and “off” dopamine agonists. Dopamine agonists increased risk-taking in Parkinson’s disease patients with active ICD symptoms, but it did not have an effect on the control. The dosage was also an important factor in explaining risk behavior. Reduced risk taking was reported for both groups in high versus the low risk condition with negative consequences involved. Researchers also found that patients with Impulse Control Disorder were not impaired in processing and adjusting to negative consequences.

Structural brain abnormalities common to posttraumatic stress disorder and depression

Kroes, M. W., Rugg, M. D., Whalley, M. G., & Brewin, C. R. (2011). Structural brain abnormalities common to posttraumatic stress disorder and depression. Journal Of Psychiatry & Neuroscience, 36(4), 256-265. doi:10.1503/jpn.100077

This purpose of this study was to investigate the relationships between grey matter reduction in the brain in major depression and in post traumatic stress disorder (PTSD). PTSD and major depression have in the past been associated with brain volume reductions in the same locations. The researchers also sought to determine if correlations existed between brain volume and perceived psychopathology as reported by the participants. This study included 82 participants: 24 had PTSD, 24 had major depression, and 29 were used in the control group. The researchers obtained sMRIs (structural magnetic imaging scans) from PTSD individuals and from those in the major depression group and in the control group. The participants reported their perceived levels of anxiety and depression. In order to determine the changes in brain volume, the researchers utilized voxel-based morphometry along with the DARTEL algorithm within SPM5. The results showed that the participant groups with PTSD and major depression had areas with smaller brain volumes in comparison to those in the control group. PTSD and major depression groups did not significantly differ from each other. In patients with PTSD, there was a negative correlation to reported anxiety and brain volume in various areas such as the inferior temporal cortex, but volume was increased in major depression participants. In those with major depression, self-perceived depression was negatively correlated to brain volume in patients with PTSD. From this study, it was determined that brain volume in individuals with PTSD and in those with major depression was similar in certain areas. There were slight differences in the reported anxiety and depression from the patients.

Alzheimer's disease: Strategies for Disease Modification

Alzheimer's is a disease that needs serious attention because beside the fact that it harms and stresses the one who is diagnosed with it also affects their family as well; on top of this it is the largest unmet medical need in neurology. This disease doesn’t discriminate many of history leaders have battled this disease. Those such as former President Ronald Reagan and Civil Rights Leader Rosa Parks are just a couple but it has had it affects on more than five million Americans. Alzheimer’s and dementia goes hand in hand. Dementia is a loss of brain function that occurs with certain diseases. Alzheimer's disease (AD) is one form of dementia that gradually gets worse over time. It affects memory, thinking, and behavior. Memory impairment, as well as problems with language, decision-making ability, judgment, and personality, is necessary features for the diagnosis. Age and family history are risk factors for AD. As you get older, your risk of developing AD goes up. However, developing Alzheimer's disease is not a part of normal aging. Having a close blood relative, such as a brother, sister, or parent who developed AD increases your risk. Having certain combination of genes for proteins that appear to be abnormal in Alzheimer's disease also increases your risk. Other risk factors that are not as well proven include is longstanding high blood pressure. An article I found was Alzheimer's disease: Strategies for Disease Modification and basically this article explain how there are and have been attempts to modifying this terrible disease. It explains how current drugs improve symptoms, but do not have profound disease-modifying effects. However, in recent years, several approaches aimed at inhibiting disease progression have advanced to clinical trials. Among these, strategies targeting the production and clearance of the amyloid peptide; a cardinal feature of Alzheimer's disease that is thought to be important in disease pathogenesis are the most advanced. Approaches aimed at modulating the abnormal aggregation of tau filaments (another key feature of the disease), and those targeting metabolic dysfunction, are also being evaluated in the clinic. This article discusses recent progress with each of these strategies, with a focus on anti-amyloid strategies, highlighting the lessons learned and the challenges that remain.

Nature Reviews Drug Discovery 9, 387-398 (May 2010) | doi: 10.1038/nrd2896

Neurological Disorders

In chapter 16 it discusses neurological and psychological disorders. The focus on neurological disorders is just as complex of those of psychological disorders. A neurological disorder is a disorder of the body's nervous system. Structural, biochemical or electrical abnormalities in the brain, spinal cord, or in the nerves leading to or from them, can result in symptoms such as paralysis, muscle weakness, poor coordination, and loss of sensation, seizures, confusion, pain and altered levels of consciousness. There are many recognized neurological disorders, some relatively common, but many rare. They may be revealed by neurological examination and studied and treated within the specialties of neurology and clinical neuropsychology. Interventions include preventative measures, lifestyle changes, physiotherapy or other therapy, neurorehabilitation, pain management, medication, or operations performed by neurosurgeons. There are many as one billion people worldwide with these disorders. An article I found that discusses this as a means to help those with neurological disorders is The Progress Stem Cells for the Treatment of Neurological Disorders. It states that many common neurological disorders, such as Parkinson's disease, stroke and multiple sclerosis, are caused by a loss of neurons and glial cells. In recent years, neurons and glia have been generated successfully from stem cells in culture, fuelling efforts to develop stem-cell-based transplantation therapies for human patients. More recently, efforts have been extended to stimulating the formation and preventing the death of neurons and glial cells produced by endogenous stem cells within the adult central nervous system. The next step is to translate these exciting advances from the laboratory into clinically useful therapies.

Nature 441, 1094-1096 (29 June 2006) | doi: 10.1038/nature04960; Published online 28 June 2006

Predictors of subjective impairment after stroke: influence of depression, gender and severity of stroke

Chapter 16 of our textbook talks about disorders of the brain and how they can be diagnosed and treated. Stroke results from a lack of blood, called ischemia, followed by cellular events that cause the real damage. The ideal treatment for stroke is to restore blood flow in the blocked vessels before the cellular events occur. There are certain medications and therapies that also help to treat stroke patients. The study I found is “Predictors of subjective impairment after stroke: Influence of depression, gender and severity of stroke”. The aim of this study was to identify some key factors that are associated with stroke survivors perceptions of their impairments. There were a total of 104 participants that had to meet certain criteria to be eligible to participate in the study. The longitudinal study was conducted from 1999 to 2003 with the help of 4 rehab centres. The patients were examined twice with their partners. Once directly after agreeing to participate and then one year later. 104 patient/spose groups gave consent and completed questionnaires on admission to rehab. One year later, 81 of the initial 104 couples agreed to participate in the study. The researcher used the Barthel Index to asses patients level of functional disability, the Patient Competency Rating to measure deficiencies in physical, cognitive, and psychosocial functioning, and performance on everyday tasks, and the Cornell Depression Scale was constructed specifically for patients with cerebral dysfunctions. Results showed the same prevalence in depressive symptoms between measurement points, only slight gender differences were found in the prevalence of depressive symptoms. At time two, the percentage of depressed men was much higher than that of women, 28.2%, 14.3% respectively. It was indicated that gender was a predictor of patients perceived impairments but that depression had no predictive value of perceived impairment. The researcher believes that their findings strongly indicate that rehabs should focus more on interventions that promote emotional coping and reduce depressive symptoms of stroke sufferers.

Wilz, G. (2007). Predictors of subjective impairment after stroke: influence of depression, gender and severity of stroke. Brain Injury, 21(1), 39-45.

http://web.ebscohost.com.ezproxy.utm.edu/ehost/pdfviewer/pdfviewer?vid=49&hid=104&sid=aa55f6e5-99fe-4d45-9098-e56892e98a8e%40sessionmgr104

Cognitive retraining in epilepsy

Chapter 16 of our textbook talks about disorders of the brain, their symptoms, and how to treat them. One of the disorders I chose was Epilepsy because my one year old nephew has this disorder. The doctors are saying he will grow out of it, his medicine has helped a lot with the seizures and we are hoping for the best. Epilepsy is where a person suffers from recurrent seizures, either idiopathic(spontaneous) or symptomatic(has a specific cause). The current research study wishes to study the effects of cognitive retraining on targeted skills areas. The measures of neuropsychological functioning were a group of tests/tasks, showing emphasis on memory, attention, and emotional state. The subject was 32 years old, male, and a graduate working in a factory. He has had epilepsy for 8 years. After the patient has seizures he often feels mentally slow and has aches and pains in the limbs that had convulsive movements. His seizures lasted 3-5 minutes and would occur 5-7 times before treatment was started.  Regular intake of anti-seizure drugs decreased his seizures but he was still having about 3 a year. He developed a fear of seizures and experienced a slow decline in his concentration and memory power which became a setback at work. A neuropsychological evaluation was performed to identify areas for needed rehab. The researchers gave him treatment in attention/concentration and memory. The treatment was comprised of cognitive and supportive therapy. The cognitive retraining included both paper and pencil tasks and real life activities aimed at improving his ability to focus and sustain attention. The training program lasted 6 weeks. Results showed an overall increase in performance across the 6 week training period. The researcher believes that their findings show that by identifying cognitive deficits in patients, effective training programs can be implemented to help regain some performance and be beneficial to epilepsy sufferers.

Gupta, A., & Naorem, T. (2003). Cognitive retraining in epilepsy. Brain Injury, 17(2), 161-174.

http://web.ebscohost.com.ezproxy.utm.edu/ehost/pdfviewer/pdfviewer?vid=29&hid=104&sid=aa55f6e5-99fe-4d45-9098-e56892e98a8e%40sessionmgr104

Brain Activation and Defensive Response Mobilization During Sustained Exposure to Phobia-related and Other Affective Pictures in Spider Phobia

Wendt, J., Lotze, M., Weike, A. I., Hosten, N., & Hamm, A. O. (2008).  Brain activation and defensive response mobilization during sustained exposure to phobia-related and other affective pictures in spider phobia.  Psychophysiology, 45(2), 205-215.  Retrieved from EBSCOhost.  doi:10.1111/j.1469-8986.2007.00620.x

In Chapter 16 of our textbook, there is a section on anxiety disorders.  The textbook notes that some of the most common psychiatric conditions are due to anxiety disorders.  There are many types of anxiety disorders, but the one that I chose my article on was about specific phobias.  When an individual has a specific phobia, he or she experiences fear or arousal when exposed to certain things in specific situations (i.e. animals, blood, heights).  The amygdala is the brain region that is known to be involved in fear learning and activation of fear and phobia.  According to this study, individuals with specific phobias have overreactive defense systems.  They also have “phobia-specific startle potentiation” of the startle reflex when they view images of the objects that they fear.  In this study, the researchers aimed to discover three things: if a sustained exposure to phobia-relevant stimuli would provoke a continuous defensive response mobilization in those individuals with specific phobias, if there would be an increase in the activation of the amygdala when shown a phobia-relevant stimuli rather than a neutral stimuli, and if there would be an increase in the activation of the insula during the processing of phobia-relevant stimuli.  Thirty-two women participated in this study.  They were asked to complete the German version of the Spider Phobia Questionnaire (SPQ).  After the participants took the questionnaire, researchers discovered that 16 participants had a spider phobia (experimental group) and 16 participants did not have a spider phobia (control group).  The participants viewed 150 different pictures from the International Affective Picture System.  These pictures were from five different categories, which included spiders (phobia relevant), mushrooms (neutral), pleasant contents (i.e. babies), unpleasant contents (i.e. animal attack), and complex neutral pictures (i.e. buildings).  There was a time lapse of three seconds between each picture that was shown.  The participants were measured while viewing the images on the eyeblink component of the startle response (electromyographic or EMG activity) and on their brain activation using fMRI technology.  The researchers found that the participants in the spider phobia group had increased activation of the amygdala when viewing the spider pictures as well as larger eyeblink magnitudes.  These results, however, are not necessarily fear specific because other pleasant pictures caused the same activation level in the amygdala as did the spider images.  Another finding was that the activation of the insula was increased during sustained phobic exposure.  The results of this study suggest that the activation of the amygdala is due to “motivationally relevant” stimuli with the activation of the insula associated with an actual or anticipated defensive response mobilization.  This study enables other psychologists and scientists to understand that there are other brain regions besides the amygdala that are responsible for fear and specific phobias.