How you feel influences what you see, it is not just what you see that influences how you feel; a top down approach to understanding the visual system.
Affective Circumplex: Affect can vary in terms of valence (positive/negative) and arousal (high/low).
A great analogy for understanding how affect (the experience of an emotion) influences perception is to think of affect as a spotlight, or a source of “attention” that sheds light on the external world. This is known as a top-down process because the cortical and sub cortical levels of the brain directly influence what one externally experiences. This is opposed to a bottom-up process wherein external stimuli influences processing in the brain (an example of this process would be hearing something hit the floor behind you and immediately shifting your attention to that object). The brain uses both of these processes interchangeably, but it has only been recently that a top-down understanding of the visual system (a system that has classically been believed to be primarily regulated by external stimuli and how such stimuli influence attention) has been accepted. Many studies by Lisa Feldman Barrett and the Interdisciplinary Affective Sciences lab at Northeastern University seem to have proved strong evidence against the popular claim that the bottom-up system is the sole means by which perception can be influenced. More
As much fun as I had exploring psychology last time I set out to write a blog post, this article from Science Daily caught my eye last week and I had to revert to my biology-related posting habit. Evidently, researchers at Oxford in the UK are using skin cells to grow induced pleuripotent stem (IPS) cells to use in their study of Parkinson’s Disease. What’s so useful about this technique is that skin cells are easily accessible, in contrast to the hard-to-reach tissues of the brain. With the skin cells obtained, the scientists plan to grow dopaminergic neurons and work on techniques for early detection of PD, perhaps finding ways to diagnose it before patients start showing symptoms. The skin cells will be from early-stage Parkinson’s patients, so they can be compared to the dopaminergic cells of healthy individuals to determine where things go wrong in the neurons affected by the disease. More
Research has been conducted that proves that our thoughts can control the rate of firing of neurons in our brain. This research reveals the crucial advancement of brain-operated machines in the field. John P. Donoghue at Brown University has conducted research that uses neural interface systems (NISs) to aid paraplegics. NISs allows people to control artificial limbs; individuals simply need to think about commanding their artificial limbs and signals are sent down from their brain to control the movement of these limbs! This great feat is not the only applicable result of current research done by brain-machine interfaces. Dr. Frank Guenther of Boston University uses implanted electrodes in a part of the brain that controls speech to tentatively give a voice back to those who have been struck mute by brain injuries. The signals produced from these electrodes are sent wirelessly to a machine that is able to synthesize and interpret these signals into speech. This is specifically useful for patients suffering from locked in syndrome, wherein an individual with a perfectly normal brain is unable to communicate due to specific brain damage, and thus allowing these individuals to communicate with the world! These discoveries are not only incredibly useful, but they also reveal the astonishing feats that the field of computational neuroscience is accomplishing in the world today.
“Magic mirror on the wall, who is the fairest one of all” says the evil Queen of Snow White and the Seven Dwarfs. I don’t deny that growing up on Disney gave me a somewhat skewed sense of reality at times. Wouldn’t it be nice to all have our own magic mirrors, constantly reminding us how wonderful and beautiful we are in the midst of the stress that is life?
A recent study by researchers at Cornell University have shown that we may actually have such a magic mirror – Facebook, as fate would have it. There are varying opinions concerning internet use on our personalities, but this study shows that Facebook can have a short term positive effect on self esteem. More
Because of the brain’s amazing and incomprehensible complexity, there are billions of neurons that connect and network all the major areas of the brain with the small intricate parts as well. So how can we distinguish one of these neurons from the billions of others?
Well, within the past five years more advanced techniques have been discovered and used on various organisms. The most prevalent, and probably the most revolutionary, has been staining. This process was pioneered in the late nineteenth century by Camillo Golgi and allowed for the staining of whole, random cells.
Since then, much progress has been made and today the viewing of even more complex and minute parts that make up the brain is possible. One extraordinary technique was developed by a team of Harvard researchers a few years ago, and it is truly beautiful.
Known as the Brainbow technique, these investigators were able to use genetics to visualize complete neuronal circuits in unprecedented detail. Up to four differently colored fluorescent proteins were used, generating a palette of 100 distinct hues that labeled individual neurons.
Here are the fluorescent proteins in their full glory illuminating the many neurons that make up the brain of a mouse. More
With the Pancakes for Parkinson’s event at Boston University nearing, on April 2nd, I thought it would be a good time to check up on the latest in Parkinson’s research.
Firstly, Parkinson’s Disease (PD) is a motor disorder that affects dopaminergic neurons of the brain, which are necessary in the coordination of movement. Onset is usually around age 60, starting with symptoms including tremor, stiffness, slowness of movement, and poor balance and coordination. While current treatments can help alleviate the symptoms in patients, none provide a cure.
Second off, the mission of the Michael J. Fox Foundation for Parkinson’s Research and other support groups is to find better treatments for those suffering from the disease. With the Baby Boomer generation entering late adulthood and old age, more research needs to be done to better understand the disease and help those with it find relief. Consider stopping by the GSU Alley for some pancakes to show your support for the Foundation and its cause next month!
Ranging from studying food intake to using technology, many approaches have been used in PD research. More
Crime is a trillion-dollar-a-year problem with the average psychopath convicted of four violent crimes by the age of forty. Although psychopathy is one of the least-funded areas of psychology, Dr. Kent Kiehl, one of the leading investigators in this field, hopes to defy this standard.
In January 2007, he requested to have a portable fMRI brought into the Western New Mexico Correctional Facility; the first fMRI ever brought into a prison. Kiehl hopes to test his theory that psychopathology is caused by a defect in the paralimbic system, which is involved in processing emotion, inhibition, and attention control.
August 25, 2009 marked the day that America, and most importantly Massachusetts, lost one of its greatest senators, Ted Kennedy. Kennedy was diagnosed with a type of brain cancer called glioblastoma multiforme (GBM) in May 2008 after suffering from a seizure. GBM is a tumor formed in the glial, or supportive, brain cells; there is no current evidence for a genetic predisposition to this type of cancer. The American Cancer Society believes that 21,000 Americans are diagnosed with brain tumors, and about 10,000 are GBMs. They are the most aggressive and common type of brain tumor, which are resistant to many types of treatments. Only 3% of patients diagnosed with these tumors generally survive five years after diagnosis.
In early 2007, a 64-year-old Swiss woman was admitted to the emergency room of a local hospital after having suffered a moderate right hemispheric stroke. Several days following her hospitalization, the woman began to experience what she described to her physicians as a “pale,” “transparent” arm that began at her elbow, which she could move and utilize to complete actions. The phenomenon the Swiss woman experienced was a Supernumerary Phantom Limb (SPL), which is characterized by the sensation of possessing an extra limb that did not exist previously. Though uncommon, conditions such as SPL and phantom limb (the sensation that a missing limb is still attached to the body) typically arise due to some form of insult to the somatosensory region of the brain or from the removal or lack of body parts.
In the healthy brain, multisensory circuits organize visual, tactile, and proprioceptive inputs to the brain in order to compose a somatotopic map of which body parts are inherently our own. However, even the normal brain can be manipulated into believing in the existence of an extra limb. More
For those of you who’ve forgotten or perhaps even repressed your memories of high school English class, the line in the title is the cry of the power-hungry and all-around homicidal maniac Lady Macbeth, the female lead in Shakespeare’s great tragedy, Macbeth. After having committed regicide so that her husband may become king, she becomes convinced that she cannot wash King Duncan’s blood from her hands. Thoughts are soliloquized, guilt is manifested in madness, and archetypes are born.