Saturday, December 13, 2014

Neuroimaging in Depression


Major depressive disorder also knows as clinical depression is a mood disorder that causes a persistent feeling of sadness and loss of interest associated with a dysregulation of brain regions including the prefrontal cortex and limbic system. The structural and functional relation between the abnormalities in these regions are far from understood in depressed patients. The symptoms are assumed arise from changes caused by both regions. 
Research Professor Scott Langenecker from the University of Illinois, Chicago provided a meta analysis of a fMRI study on how emotional valence modulates brain functional abnormalities in depression. His research entails The riddle of Depression: Failing to Learn and take Advantage of Optimized opportunity. It is critical to consider models of emotional dysfunction in depression, and therefore emotional valence is an important moderator when understanding neural abnormalities in depression.
At the Academic Medical Center in Amsterdam Dr. Bart de Kwaasteniet and his colleagues used a multimodal neuroimaging approach to further investigate this relationship between structural and functional abnormalities in these brain regions in depressed patients. In the meta analysis presented by Langenecker, the neuroimaging study conducted by Groenewold al et. in emotional process in depression patients was not consist with the model that describes neural association with biased emotion processing. Kwaasteniet’s and his colleagues conduced multiple neuroimagining scans of patients healthy and those with depression. They focus on the two regions that are connected by the uncinate fascicles which are know to be involved in the region of emotion.  The two regions consisted of the subgenual anterior cingulate cortex and the medial temporal lobes, which have been focused on increased activation in models describing the neural correlates of biased emotion processing in depression patients. 
This meta-analysis preformed by Groenewold al et. integrates these findings and examines whether emotional valence modulates such abnormalities since they are initially inconsistent with the model. According to their results Depressed subjects also showed reduced activity in left dorsolateral prefrontal cortex for negative stimuli and increased activity in orbitofrontal cortex for positive stimuli.
Kwaasteniet’s results from the neuroimaging scans lead him into developing a new hypothesis that  brain structure abnormalities  lead to differences in connectivity between brain areas in depressive disorder, which may have been why the meta-analysis preformed by Groenewold al et. was inconsistent with the model of neural association of biased emotion processing in depression patients. 








Elsevier. (2013, July 8). Brain structural deficits may contribute to increased functional connections 

between brain regions implicated in depression. ScienceDaily. Retrieved December 1, 2014 from 

www.sciencedaily.com/ releases/2013/07/130708103156.htm


Groenewold, N. A., Opmeer, E. M., de Jonge, P., Aleman, A., & Costafreda, S. G. (2013). Emotional 

valence modulates brain functional abnormalities in depression: evidence from a meta-analysis of 

fMRI studies. Neuroscience and Biobehavioral Reviews, 37(2), 152-63. 

10.1016/j.neubiorev.2012.11.015


NSA's Application of Threat Detection for Unidentified Stimuli

I have always been interested in the idea of facial recognition, how it works in both the human perspective and how it can be applied in this day and age with the technology we have. I came across an article talking about the NSA and their use of Facial Recognition. By using the internet, the NSA is able to download hundreds of millions of images which they can use to cross-reference and then successfully create recognizable patterns through complicated algorithms. This correlated mostly with me with the research talk done in class “Familiar novel discrimination and threat detection for unidentified stimuli”. In this study, the experimenter was studying the ability for the brain to (quickly) correlate recognizable images and non-recognizable images (demonstrated with the use of famous people’s images) and how they may or may not stir up a defense mechanism (they are seen threatening).
                It’s interesting that the brain is already working at a capacity at which the memory can store recognizable images to the point of subconscious recall. At the same time, programs are finally reaching this level of technological advancement which can attain such a degree of information at a reasonable pace. The conclusion of the experiment with the brains recall process correlated to a human evolutionary idea which the brain is able to connect ideas or emotions connected to certain information given, which can then lead to a determination of response. This information can actually be useful to the study of the NSA’s use of facial images for facial recognition because it means that it is no longer necessary for images to be complete frontal and high resolution pictures to work with an algorithm to make their recognition software more capable. Instead a more specific algorithm, which through deeper study of the brain and more intense coding, can mimic the operations of the brain at its natural level and thus make the program more useful on less “desirable” but easier to attain images.
                Billions of dollars from the government and private sector is already flowing into projects such as these relating to facial recognition, so although the level of expertise needed to make the application of the study to this new software is incredibly high, the funding is present and the results and uses of this application is extremely necessary in this time and age.

Resources:

Cleary, A. M., Ryals, A. J., Nomi, J. S. (2013). Intuitively detecting what is hidden within a visual mask: Familiar novel discrimination and threat detection for unidentified stimuli. Memory and Cognition, 41(7), 989-999.

Risen, James, and Laura Poitras. "N.S.A. Collecting Millions of Faces From Web Images." The New York Times. The New York Times, 31 May 2014. Web. 10 Dec. 2014.

Friday, December 12, 2014

Meditation and stress



Maher Hamadeh


With the rise in modern day smart phone technology and other user-friendly devices, over stimulation has been very common. People are constantly distracted with work, school, meetings, communication, social media, Internet shopping, etc. Unlimited Access to all of this can make excessive multitasking all the more tempting, leading to mind overload. Just like the human physical body, the mind needs a break from constant external stimulation. The lack thereof may take its toll on overall mental health. This type of break or mindfulness meditation has been found to reduce overall stress.
Most research focuses on lengthy meditation program benefits, however research conducted in Carnegie Mellon University showed that brief mindfulness meditation practices-“25 minutes for three consecutive days"-alleviates psychological stress. The article, Just 25 minutes of mindfulness meditation alleviates stress presents a 3 day experiment done by Creswell and his research team, testing 66 healthy individuals aged 18-30. After 3 days of brief breathing meditations, individuals reported their stress levels in response to stressful speech and math performance stress tasks. Reduced stress perceptions to the speech and math tasks were found, indicating that the mindfulness meditation fostered psychological stress resilience
Grabowecky’s study, Attention regulation and monitoring in
Meditation, illustrates that she also believes multitasking and overstimulation is a big issue. She even refers to this phenomenon as the rise of “the Zombie Nation”. Mindfulness and controlled attention, according to her, is the gateway to awareness and happiness. Without the isolation and attention designated to concentrate attention, the mind’s autonomy can be compromised by the outside world. Her studies showed many positive correlations between mediation and health. The Amygdala response to negative distracting sounds decreases with years of meditation practice. Post-retreat telomerase activity was also significantly greater in the retreat group. The last I will mention is that long-term meditators have thicker cortices in the colored regions.
The cultivation of emotional and mental states is also another profound effect meditation has. This allows people to assess stress levels faced from day to day. Aside from stress, meditation can also sustain or treat more severe conditions such as Depression since it has been shown to have a direct relationship with stress. Eliminating the stressors may be an effective treatment for many types of Depression.


Carnegie Mellon University. (2014, July 2). Just 25 minutes of mindfulness meditation alleviates stress, study shows. ScienceDaily. Retrieved December 12, 2014 from www.sciencedaily.com/releases/2014/07/140702122535.htm













The Meditating Mind Captured in Action


Meditation is a thousand-year-old practice that is widely popular around the world with many known benefits. Within the last few decades we developed technology to dive into the human mind and actually see what is happening inside the brain. Technology, such as MRI, is now helping researchers study what actually happens during meditation. In her lecture, Dr. Grabowecky mentioned how she found meditating extremely helpful in her life and now aims to encourage others to meditate as well. The two most common types of meditation are focused attention and open monitoring or mindfulness. Focused mediation is characterized by focusing all attention at one point, while mindfulness meditation is simply allowing the mind to flow freely and be aware of emotions and sensations without reacting to them. Both types are actively studied around the world to determine the effects and benefits that they can offer. In her study, Dr. Grabowecky found out that open monitoring participants were more successful at focusing more effectively on unexpected stimuli than the focus attention group.

At the Norwegian University of Science and Technology, a team of researchers is studying the difference between the two meditation styles with the help of an MRI machine. The most surprising result of the study is that open monitoring meditation actually leads to higher neural activity than at a state of rest. In contrast, when the participants performed focused attention meditation the neural activity was nearly equal to a state of rest. The finding might be a reason as to why the open monitoring participants in Dr. Grabowecky’s study performed better than the focus attention group. A member of the Norwegian University’s team, Dr. Xu said, "I was surprised that the activity of the brain was greatest when the person's thoughts wandered freely on their own, rather than when the brain worked to be more strongly focused.” This helps us better understand what is happening during meditation. With each meditation study, we are stepping closer to unlocking the secrets of meditation and the neural mechanisms behind the ancient practice.





References:

Jian Xu, Alexandra Vik, Inge R. Groote, Jim Lagopoulos, Are Holen, Øyvind Ellingsen, Asta K. Håberg, Svend Davanger. Nondirective meditation activates default mode network and areas associated with memory retrieval and emotional processing. Frontiers in Human Neuroscience, 2014; 8 DOI: 10.3389/fnhum.2014.00086

Lutz, A., Slagter, H. A., Dunne, J. D., & Davidson, R. J. (2008, March 10). Attention regulation and monitoring in meditation. Cell Press Neuron, 12(4), 1-7

The Norwegian University of Science and Technology (NTNU). (2014, May 15). This is your brain on meditation: Brain processes more thoughts, feelings during meditation, study shows. ScienceDaily. Retrieved December 12, 2014 from www.sciencedaily.com/releases/2014/05/140515095545.htm