Lexix Rodriguez
Mind Body Brain
15 of March 2018
Neuroimaging and Cognition
Psychology seeks to explain human behavior and the mental processes that lead us to encode information otherwise known as cognition. However, in order to further understand the reason behind our decisions, the source of our creative thinking, or even the mental processes behind our behavior, we must further research the neural activity in our brains to analyze these senses. The advancements in neuroimaging techniques have played a pivotal role in the understanding of both behavior and cognition. The breakthroughs in neuroimaging has led researchers to observe brain activity during cognitive and behavioral tasks, thus leading to an in depth understanding of the relationship between complex behaviors and our brain. Neuroimaging techniques have been the pioneers in psychological breakthroughs that have helped us understand the neurological activities behind memory, encoding,emotions, learning, language, diseases and pretty much anything that has to do with cognitive processing and behavior. It has been through the study of our brain and its neural activity that we have been able to create breakthroughs of information and a deeper understanding of our brain. The development of neuroimaging techniques such as: Positron Emission Tomography (PET scan), Functional Magnetic Resonance Imaging (FMRI) and Electroencephalogram and Event-related Potentials (EEG) have individually offered different insights on brain activity depending on what each scan measures. However, one of the limitations of neuroimaging includes the concept of reverse inference. Reverse inference refers to the practice in which researchers fail to take into account how under a mental task the activation of one part of the brain is correlated to that part; however if another part is activated it should not be strictly associated with the task itself. With this in mind it is important for us to be able to distinguish the different measurements of brain imaging and how these results can conclude interesting findings of our brain and cognition.
One of the most used forms of neuroimaging in cognitive neuroscience is Functional Magnetic Resonance Imaging (fMRI). The methods used for fMRI range between invasive and noninvasive techniques but the method that is mostly used is the BOLD technique. Functional magnetic resonance imaging measures the changes of metabolic activities that increase blood flow and oxygen levels in the brain caused by neural activities (Xue, Lu, Dong & Chen, 2010). It is through the BOLD (Blood, Oxygenation,Level, Dependent) technique that enables us to detect the differences in magnetic sensitivity of oxygenated hemoglobin and deoxygenated hemoglobin. It is the neural activities in the brain that can alter oxygen levels due to their consumption of oxygen which therefore increases the level of responses for BOLD oxygen levels in the blood. BOLD fMRI indirectly measures neural activities in the brain, but studies have found strong evidence that there is a strong correlation between neural activity and BOLD responses. It is because of this strong connection that BOLD fMRI continues to be one of the most common used neuroimaging techniques available (Xue, Lu, Dong & Chen, 2010).
In a study that challenges the interpretations made by neuroimaging techniques on social group processing, researchers use fMRI to measure the parts of the brain that activate when recognizing people by race and the indirect ways we measure these social groups. The study takes ten black and ten white American subjects to memorize images of varied black and white subjects with antique objects. After memorizing the stimuli, the subjects were able to recognize the faces of their same race faster. Although the activation of the fusiform face area (FFA) was higher in white subjects than black subjects, it did not explain the behavior and cognition behind this race bias ("Race, Behavior and the Brain: The Role of Neuroimaging in understanding Complex Social Behaviors", 2003). In an effort to clarify this racial bias, the researcher decided to test the relationship between activation of the amygdala and the behavioral measures of racial bias. To test this, the researchers presented the same subjects with black and white unfamiliar faces and were asked to classify for race as quickly as possible. They were also asked to classify words into good or bad.
On a different trial the participants were also asked to do the same task combined with the faces as quickly as possible. The faces and words (black, white, good, bad) were changed and reversed a couple of times. The results of this study on the fMRI imaging test showed that there was a greater activation of the amygdala for black faces but it was not for all participants. What was found was an interesting pattern and correlation in which the subjects who had greater negative bias on race evaluation had greater amygdala activation to black faces rather than white faces. However, Phelps and Thomas conclude how although the amygdala was activated it does not explain the reason behind it. As the study suggest (2003) “An activation response does not inform us as to what exactly, a brain region does in the generation of a behavior†(Phelps, Thomas). This relates to the ideas behind cognition and behavior by showing how unconsciously we learn to categorize different social groups due the conditioned responses that we attain from society. The amygdala playing a role in emotional responses showed an interesting pattern in which the people who reacted to black faces had a greater negative bias which is reflected in their learned associations and stigmas created by society. Although the conclusion of Phelps and Thomas study play a part in social cognitive behavior, it does not quite explain the sources behind it, nor the ways that negative bias plays a part in our cognition.
In terms of measuring how cognition plays a part in behavior and cognitive processes, the neuroimaging technique Electroencephalogram and Event-related Potentials (EEG) offers a different type of measurement for brain activity. EEG consists of placing electrodes on the scalp to measure small changes in voltage produced by simultaneous neural brain activity. Although It offers sufficient quality for temporal resolution, it fails to offer spatial resolution which makes it unsuited for deep brain structures (Norbury, 2018). EEG recordings offer researchers the ability to see flow of information in real time. In the article Neuroimaging for drug addiction and related behaviors (2011), the researchers explain the reasons why EEG is becoming more accessible. They state “Other neuroimaging technologies cannot achieve such temporal resolution because blood flow and glucose utilization changes are indirect measures of neural activity, and the methods to record them are slow. Thus, PET and fMRI are less well suited for determining the neural chronometry of a certain brain function†(Parvaz, Woicik, Alia-Klein, Volkow & Goldstein, 2011). Although PET and fMRI scans offer an in depth resolution for deep brain structures, EEG offers researchers the ability to study brain waves in real time thus leading to the source of how different information is processed.
In a study conducted by Dietrich and Kanso (2010) they review creativty and which parts of the brain are associated with it by using EEG. EEG and creativity has been researched in the early 1990’s moving away from its traditional measures of mental processing. In an effort to prove that creativity or as it mentions “divergent thinking†is not solely limited to the right hemisphere of the brain, researchers use EEG in measuring four themes for divergent thinking effects. The themes used for research and classification were: “(a) laterality, we examine the evidence for the involvement of (b) the prefrontal cortex, (c) temporoparietal regions, and (d) all other brain structures†(Dietrich & Kanso, 2010). By using these themes or regions of structures they involve parts of the brain that can be heightened during divergent thinking. With the data received from the different tasks that were performed they found that the creative task provoked “…an increase in EEG power in the Beta 2 and gamma bands. Induction had a much stronger effect on the cortex than the creative task†(Danko, 2009). What this means is that an area not necessarily associated with the creative task was activated. With this study they failed to get meaningful data of supporting that creative thinking was solely a right hemisphere process. What they did find was that divergent thinking specifically involves all both hemispheres of the brain and other cerebral areas. However, they decided to create another study in which they got subjects to do some artistic creative tasks.
The researchers Bhattacharya and Petsche created a series of studies using EEG neuroimaging for the study of creativity and cognition. The subjects of the study ranged between novices in art, experts and amateurs. By using variables of both genders, subjects of all ages and different professions depending on the task at hand, they were able to differentiate the findings. During each task at hand they were able to distinguish different activation of cerebral areas depending which resulted in an activation of several temporoparietal areas. What was found resulted in the conclusion that artistic creativity should not be restricted to the workings of the right hemisphere of the brain, but rather an interaction of multiple cerebral regions and hemispheres (Dietrich & Kanso, 2010). The study (2010) concludes that creativity is not associated to any brain region specifically with exception to the prefrontal cortex. What was found for the prefrontal cortex was changes in brain activity caused by creative cognition. These conclusions came about as the EEG studies created an increase in synchrony which indicated a cooperation of the brain with the task at hand (Dietrich & Kanso, 2010). The implications of this study offers us the ability to further understand the interchangeable connections that our brain has with all hemispheres and lobes. This debunks the idea behind left brain vs right brain personalities by creating a deeper understanding that our brain will interchangeably use all encoded information to further assist on whatever task is presented.
Neuroimaging techniques are now considered the windows to our minds and have each led to individual advances dependent on what each technique measures. Although there are different measurements that neuroimaging techniques offer, it is understood that each separately or combined offer a wider range of brain mirroring for information on neural activity and cognition. It is because of the countless research and studies that have led to a range of diverse topics within the field. Studies such as the “Race, Behavior and the Brain: The Role of Neuroimaging in understanding Complex Social Behaviors", offer us an insight on the ideas behind racial bias and how it is rooted in our amygdala and conditioned responses by the society each subject lived in. The social contributions that studies like these offer are the ability to remand human behavior and commence a decoding process for whatever racial bias was encoded beforehand. Although it seems as a drastic approach to the findings, it does not take away the possibility of learning how to encode the information and asses the social problem at hand through the processes of cognition.
Likewise, in the EEG study we were able to further assess the discussions on left vs right brain and where creativity lies in our brains. Although EEG does not offer an in depth view of brain structure, it does offer an understanding of which areas react to creativity and from what hemispheres or lobes they’re coming from. Although there is no definitive conclusion as to which part of the brain is the source of creativity, we can conclude from the research that our whole brain is connected in helping us deal with such tasks. Both studies offered an insight in cognition and how neuroimaging helps answer questions that once were unknown. The advances in neuroimaging techniques are still progressing and it will only take a matter of time for researchers to further understand the neurological aspects of our brain and asses cognitive processes and behavior.
Bibliography
Dietrich, A., & Kanso, R. (2010). A Review of EEG, ERP, and Neuroimaging Studies of Creativity and Insight. Citeseerx.ist.psu.edu. Retrieved 14 March 2018.
Parvaz, M., Woicik, P., Alia-Klein, N., Volkow, N., & Goldstein, R. (2018)
Neuroimaging for drug addiction and related behaviors. NCBI. Retrieved 14 March 2018.
Phelps, E., & Thomas, L. (2003) Race, Behavior and the Brain: The Role of
Neuroimaging in understanding Complex Social Behaviors.
Psych.nyu.edu. Retrieved 12 March 2018.
Xue, G., Lu, Z., Dong, Q., & Chen, C. (2010). Brain Imaging Techniques and Their Applications in Decision-Making Research. National Center for Biotechnology Information. Retrieved 12 March 2018.