Human Split Brain Study

One Brain or Two?, Michael Gazzaniga and Roger W. Sperry explore the independent abilities of the two hemispheres in the brain, the left and right, by studying split-brain patients and their responses to certain tests. The tests are designed to examine the mental and perceptual capacities of the split-brain patients. With careful placement of objects or pictures, the first test measures the visual abilities of the patients. The second test measures the tactile cognition abilities of the patients by allowing them to feel an object behind a screen, then asking them to name the object. The third and more challenging test combines the visual test and tactile test to measure the auditory abilities of the patients. Each of these tests shows the different ways that the brain works in split-brain and normal brain humans alike.

Dr. Jill Bolte Taylor describes her experience of a stroke in her left hemisphere on December 10, 1996 causing her to lost the ability to move or talk, as well as her self awareness. Throughout her presentation, she mentions the basic functions of the two hemispheres of our brain: right and left hemisphere. Taylor argues both sides of the brain functions differently and process various of information. Taylor defines the right hemisphere of the human brain is about the “present moment” or “right here, right now”, it processes with pictures and learn physically based on our movements. She compares the right hemisphere to a “parallel processor”, whereas she compares the left hemisphere as a “serial processor”. Taylor defines the left hemisphere

The other test held was an auditory test. The test was done in two different ways. One way was finding the objects in a bag that were mentioned verbally and the other was identifying the item reached by touch. This test’s results were also supporting the previous researchers’ logical conclusion about the left hemisphere ability of speech. It confirmed the right hemisphere’s ability of comprehending language and its ability of expressing it in a nonverbal way. During the test, evidently, the right hemisphere had no trouble identifying the unknown objects by touch as the left hemisphere did. Moreover, some three- dimensional drawings of the slit-brain patients, who were all right handed, developed much better drawings using their left hands compared with their right hands.

As shown in the chart, the split brain has a low correlation than the intact brain, which has a higher correlation. This proves that a person with a split brain cannot process information to the left and right. Face recognition is in the right side of the brain while vocabulary and reasoning in the left side of the brain. When comparing face and reasoning it only gave a low correlation same with face and vocabulary. Vocabulary and reasoning is in the left hemisphere, therefore, being a bit more stronger than the rest of the results. In the intact brain reasoning, vocabulary, and face are being processed to the left and right showing that they are laterized.

In which exact placement of an object or word mattered if the image went to right brain or left brain. Tactical stimulation in which the participants were asked to feel the object but could not see it. And testing auditory was the hardest one they said because the sound enters through both of your ears so they are sent to both sides of your brain. But you can minimize to one side of hemisphere as Gazzaniga explained in his methods. After performing all this methods he revealed some fascinating findings about brain functions. With visual ability he said that both sides of your brain are equally skilled for visual perception. But when the lights were flashed on both sides of brain and the patients could only see the ones on the right because the center of speech is located on the left side of brain so in order to say that you saw the light the object have to be seen by the left side of your brain. With the tactile stimulation same thing was done but this time the object was placed in their hands and since the left hemisphere have verbal abilities it was easily identified the object that was placed in right hand but with left

In class on 9/18, we discussed the structures of the brain and how each part works. The brain has so many parts that it is almost impossible to remember all the parts and their functions. The brain is very complex, but the most interesting thing that was talked about was the two different hemispheres. We discussed how the right hemisphere controls the left side of the body and vise versa I found it very interesting that the left side of the brain controls more of our logic and grammar, and the right side of the brain controls more emotional expressions. When Dr. Yarnell discussed her story of her friend and her friend’s husband getting in a fight I think the way she told her to help resolve it was very interesting. Her response was to move into her left side

Mead & Hampson (1996) developed a study involving the divided visual field paradigm and a phonological rhyme/non-rhyme task to test the speed and accurateness of either side of the brain. This study was used to investigate functional asymmetry between the left and right hemispheres in phonological processing. The research was taken out equally on 15 male and 15 females London Metropolitan University students ranging from ages 18 – 35 years old. They were all specifically chosen to be right–handed and had English as their first language thus providing a fair experiment to see whether our left hemisphere (left side of the brain) or the right hemisphere is faster and more accurate. In conclusion using the mean and standard

The most modern evidence comes from neuroimaging. The N170 ERP was instrumental in highlighting brain activation when viewing face stimuli. The activation patterns helped to locate the fusiform face area (FFA) because N170 was so distinct to faces. In this essay the fMRI research into the FFA will be explored in detail. To prove faces are special, the research aimed to find a correlation between distinct face-processing brain activity and a specific brain region. The FFA was discovered in 1997 by Kanwisher. It was first described as a brain region which only responded to faces. In fact, activation was found for cat faces and cartoon faces (Tong et al, 2000). There was also some very low level activation to animals, houses and

In 1967, M.S. Gazzaniga studied the split brain in man. Gazzaniga wanted to study how the two halves of the brain functioned independently. Since it a little unethical to snip the peoples corpus callosums just for fun, it wasn‘t until doctors discovered that cutting the corpus callosum could actually cure severe epileptic seizures that it was possible for Gazzaniga and Sperry to study them. They found that the test subjects intelligence, personality, and emotions had not changed. We use each half of our brains for specific skills. Three different tests were designed to check mental capabilities. It was found that the left-brain is better at speaking, writing, reading, and math, and the right brain is better at recognizing

The hypothesis of the researchers used the abstract would distract participants from the face memory to enhance out group heterogeneity bias. The experiment included grayscale images of forward facing males. The images looked black and white photograph. The image was five inches tall and three point five inches wide. Four images were white men with neutral facial expression. African American men with neutral expression and four image with an angry expression .The participants watched the images which was presented one at a time. The order of the images were random. If the images were in the same order it would make it more memorable. Making the order of faces random prevented order effects from systematic errors could influence the results of the study one group viewed the image for half a second. While the second group viewed the image for one second. The third group viewed the image for four seconds. The researchers gave each group a different amount of time to view the image to vary the cognitive load. Next the participants watched a film of landscapes for five minutes. The film was used as distractions for the faces that was just seen. The distractor prevented the participants from

Julian Keenan’s Cognitive Neuroimaging Lab in the Department of Biology. As a research assistant, my responsibility was researching related studies to update the literature review section of Dr. Keenan’s journal article. The journal article is on eye-tracking and self-face recognition and its manuscript is under review. Once the reviews are finalized, the publication will list me as a co-author. In this position, I gained experience in researching the literature, and learned some specifics about the cognition of self-face recognition versus recognizing other faces.

Everyone is familiar with the famous Rubin face-vase drawing, a black and white print in which one can simultaneously perceive faces by focusing on the black ink or a vase by focusing on the white. If I announce that this is a picture of a vase, am I right? However you announce you see a picture of two faces, are you right? Who’s right? Are we both right? Or are we both wrong? Is it right and wrong; good and evil? I believe neurobiological research, as well as personal anecdotal study; have demonstrated that dichotomous thinking, (mental duality) is an appropriate expectation for developing brains. However an evolved adult brain has developed the ability (free will) to reconcile their emotional reactivity with

Prosopagnosia, also known as face blindness, is a form of visual agnosia characterized by an inability to recognize faces. Usually those with Prosopagnosia are able to see the features on a person 's appearance with little difficulty; however, it is the retention and synthetization of those images that challenges them. Many people also report deficits in other aspects of face processing, such as judging age or gender, recognizing certain emotional expressions, or following the direction of a person 's eye gaze. Currently, scientists have yet to come to a consensus on the actual cause of the disease, but many suspect it is linked to extensive damage of the occipital and temporal lobes. Presently, one speculation is that Prosopagnosia is connected to the fusiform gyrus, an area of the brain located on the inferior/median temporal lobe. As found by researchers, “the fusiform gyrus is thought to constitute a “core” visual representation system for faces, in part because they show face selectivity and face repetition suppression” (Furl, N., Garrido, L., Dolan, R. J., Driver, J., & Duchaine, B., 2011, 1723-1740). However, looking at recent fMRI studies, scientists are questioning whether these conditions and damages to the fusiform gyrus relate to face processing skills at all (Furl, N. et al, 2011). Due to this uncertainty another theory has evolved. As stated by Gainotti (2010, 763-766), “prosopagnosia is due to disruption of purely visual entities, the face

The ability of the human visual system to integrate facial features into a gestalt whole is one of the processes that seems to contribute the most to human face perception (referred to as holistic face processing; Taubert et al.; 2006). A large number of behavioral studies provide evidence that demonstrate that faces are processed holistically. Two examples that provide evidences for holistic processing are the composite effect and the part-whole effect. In composite effect tasks, participants are required to decide whether two identical top halves are the same (Goffaux & Rossion, 2006; Le Grand, Mondloch, Maurer, & Brent, 2004; McKone, 2008). Evidences suggest this task is more difficult when the two top halves are paired with different bottom halves, indicating that perception of the identity of features in one half of a face is changed by a whole-face

Facial recognition is a very important task and process that we need. Because that is how we assess who is someone familiar or a stranger which is very important for our safety. An article written by Meng Ming and Pallet P. Pamela (2015) titled Inversion effects reveals dissociations in facial expression of emotion, gender, and object processing talks about how there are differences in processing of facial expressions for emotion, gender and objects. According to the article “It has been proposed that the FIE results from an orientation dependent processing scheme, in which upright faces trigger primarily holistic encoding, while inverted faces and objects recruit a more feature based approach.” (Meng, Pallet, 2015, p. 1). In other words, according to Meng and Pallet’s (2015) article a possible reasoning or explanation for facial inversion effect or FIE is because of our own brain’s way of processing information and that upright faces bring about one way of processing the information and inverted faces brings along another route that is more specific.