Introduction; background information on Obesity
Obesity is a condition where somebody becomes big with a lot of gross fat, or when they are said to be overweight. To define obesity, one should bring into consideration factors like age, sex and height of the individual in question. Precise definitions have been given in relation to a person’s body mass index. BMI is an index used for relating a person’s height with their weight. Using this, one is said to be obese when their Body Mass Index (BMI) is 30 and above. However, it is essential to consider the body build of a person when relating BMI to obesity. Very muscular people tend to have a high BMI without any health risks.
When diagnosing one for obesity disorder, several things are done. Taking a health history is the first step of diagnosing for obesity in an individual. Weight gain and weight loss activities are significant factors a doctor will consider when examining a patient. These would include a change in eating habits by the patient. Adopting a different diet pattern or use of appetite control methods are some of the keynoted procedure the doctor will take when examining a patient. Prior issue of health, either physical or emotional are factors that an examiner will consider an interest in during an examination. One major thing associated with obesity is family history. Existence of cases where obesity is linked to the family makes it essential to look at it as a factor when examining a patient for obesity. The next step is to take a general physical examination of a patient. The physical examination will include a measure of height, temperature and blood pressure of the individual. The examiner will be keen on listening to the patient heartbeat rate and also the breathing patterns in the lungs.
As indicated earlier for one to be said to be obese, their age, sex and height are taken into consideration. The body mass index is used to link all these factors with an individual’s weight and helps in determining if they are obese. When the BMI comes up as above 30, then the patients’ health is said to be at risk. Other than a person’s BMI, the waist circumference is a point of interest with this condition. Most fat predisposes the body to health risks such as diabetes and heart diseases. It is scientifically proven that women with a waist measurement of more than 89cm or men with a waist measurement exceeding 102cm have more health risks than people with smaller waists.
Obesity is mainly related to the increase in body fat in the body. Scientifically, a lot of body fat in the body impairs the brain. This explains the cognitive problems visible in overweight children and adults. Most children who are obese tend to have minimal physical and mental activities. Their learning is slow and academic performance is usually below average. They tend to eat more frequently than other kids. Obesity is said to impair the brains activity bt compromising the hypothalamic control of energy in the body—the results of this lead to reduced activity among obese and food cravings. Adults who are overweight have reluctance in engaging in any form of physical activity.
Traditionally obesity has been linked to conditions such as diabetes and heart-related diseases. A recent study shows that the brain is another body organ that is affected by the increase of body fats in the body. Parts of the brain that are theorized to be linked to the cognitive effects among obese individuals are said to be hippocampus, frontal lobes and cingulate gyrus. These parts are related to the cognitive strengths of an individual and once affected, they lead to the behavioural changes among obese individuals. The figure below gives an illustration of the effects of obesity on the brain, parts affected and their impact on the cognitive capabilities of the individual.
Obesity has been linked with a reduction in brain size. Obese individuals are believed to have a 2.4 per cent decrease in their brain size as they progress with maturity. This is usually associated with the reduction in parenchymal volume with comparison to healthy individuals. As earlier stated, the brain areas that are easily affected by an increase in general body fat in obese individuals are the hippocampus, cingulate gyros and frontal lobes. Increase in the body fat, which impairs these three parts, and for ten years, there is a decline in the general execution function of such an individual. Increased BMI is linked with brain atrophy in obese individuals. This is due to the reduction in the fiber bundle length (FBL). Modification of the FBL increases with age and a relative increase in BMI. Studies show that extensive cerebral atrophy in obese individuals is the reason behind the cognition impairment among individuals with higher body index mass (BMI). When the condition is not checked, the cognitive impairments tend to increase within age and BMI.
Functional magnetic response imaging (fMRI)
Functional magnetic response imaging is a technique used to monitor the flow of blood in the brain when a person performs a task. The method is based on the fact that neurons in the brain that have an increased blood flow during an activity are the most active parts of the brain at the time. The method is used to detect abnormalities in the brain that cannot be identified by other imaging techniques. It looks and evaluates the parts of the brain that are handling certain functions of the brain in an individual. By understanding the effect of certain diseases on the brain, doctors can guide on proper treatments of the health conditions at hand. The method uses the blood-oxygen-level-dependent contrast. This is a machine that scans the activity in the brain by imaging the flow of blood in the brain. By use of the mapped blood flow into the brain, physicians can monitor the brains activity and other related spinal responses. The method has been preferred since it does not require any surgical procedure to reveal the brain or injections. Although the procedure is affected by noise, the analysis of the results is done statistically to enhance the results that come up. The results acquired by the scan done using this method can be represented graphically enhancing comparison and future references of the analyzed condition.
Effects of obesity on brain functioning have also been studied using the same method. Studies done using this method have shown the relationship between obesity and some of the behaviour shown by obese individuals. The method is used by inducing stimulants into the body of the patients; one of the methods used was inducing glucose into the body of an obese patient and another healthy patient. The doctors used the BOLD scanner to look at the responses of the hypothalamus in the brain. When an individual takes in glucose, the hypothalamus is supposed to show inflow of blood as compared to before. This is because of the need to regulate the energy flow into the body from the ingested glucose. The healthy patient, showed blood flow into the hypothalamus over a short period times. His rate of flow was normal showing that his urge to feed was just ok and in the expected rate. The hypothalamus controlling homeostatic and non-homeostatic drives to eat was the most focused on in the study. For obese individuals, their hypothalamic inhibitory responses are delayed. Their blood flow to the hypothalamus, which is supposed to be quick for a normal person is delayed leading to the high appetite among the obese individuals. These results indicate the effects of high BMI that lead to secondary obesity.
By the study of the brain activity, physicians can monitor dietary responses of the brain that may lead to secondary obesity in obese individuals. The analysis that is gotten can then be used in finding treatment that can ensure obese individuals are not predisposed to the secondary obesity, and can also be treated of their current condition—the use of FRMI in understanding the responses of obese people to food-related issues. The brain of these individuals tends to have low inhibitory responses to eating and more appetitive responses. These responses are the main motivation drive that obese people have to eat. The process gives clear information on the gut hormones that are influential in the way obese individuals respond to food-related stimuli. Normal weight individuals and especially children have greater memory and cognitive control when in response to either food or images of high-calorie foods. For the obese or overweight children, they are more prone to forgetting and therefore rarely recall the fact that high-calorie foods are unhealthy for them. Their memory activation time is very low compared to lean children. Their brain inhibitory senses for food respond slower than that of lean children.
The method has been used widely in finding other factors other than the increased appetite among children and adults that are likely to lead to more conditions of obesity. The poor school performance in studies and physical activities and the increased appetite have all been associated with brain disorders by the use of the Functional Magnetic Response Imaging BOLD scanners. This process shows great potential in coming to a solution that will solve obesity as a health menace in the world. The condition being a cause of other diseases such as diabetes and heart-related diseases, once eliminated, will ensure that other related diseases are also prevented.
Event and related potential. (ERP)
The event-related potential is referred to as the measure of brain response with reference to the direct result of specific cognitive, motor or sensory event. One might also say it is the psychological response of the brain to a stimulus. It is an invasive method of studying the brain by studying its functioning. This method makes use of electroencephalography (EEG). The method is widely used in many areas. Its applications go as broad as in cognitive psychology and neuroscience. By use of stimuli to study different conditions of the brain, neuroscientists can account for the time the brain communication and information processing timings of the body. The method is essential in measuring aspects of cognition that are not observable by behavioural methods, perceptual processing speeds, and attentional selection. The method has been found to treat well addictive behaviours due to its ability to study non-behavioural responses of the brain. The method can be used to analyze persistent appetites among obese people a provide physicians with the best approach toward the health issue. When the cognitive parts of the brain that are studied with this method, and the factors promoting obesity that are not displayed by behavioural means are exposed then the treatment of obesity can be easy to come by.
By use of lean and obese participants, research was done using the method to determine the cognitive responses of individuals who are obese. The aim was to see the brain responses of some teenagers in when in the presence of food and non-food pictures. The food pictures were subdivided into high-calorie foods and low-calorie foods. The pictures were set in a way that each would attract the attention of the participants differently. A hypothesis had been made that the participants would, of course, show increased attention to either of the pictures presented to them. This was evident in the increase of P300 amplitudes when the pictures were presented to them. The participants were normal weight adolescents and obese adolescents. The normal weight adolescents showed preferential processing for high-calorie foods. This was, however, in contrast with the overweight/obese participants. This group did not show any change in their P300 amplitudes with a change in the amounts of calories in the food pictures presented to them. Their distinction was, however, clearly shown in the difference between food and non-food pictures that were presented to them. According to the incentive sensitization theory, there is weaker sensitization when low-calorie food is presented, leading to a lower cue reactivity. Higher calorie foods tend to bring a higher reactivity cue.
While it is expected that the group under study would show different P300 amplitudes with regard to the food and non-food pictures, the main difference that comes up between the overweight and normal-weight adolescents is in the processing of the lower-calorie foods. While the P300 amplitude of the normal weight students for the low-calorie foods is low, the overweight students show no variation for either of the foods. The results show the lack of preference in the diet for the over-weight participants. Their lack of preference can be used to explain the reason behind all the weight gain and high appetite all through their lifetime. The method shows that obesity for some is not as a result of their lifestyle choice but rather a consequence of their brain functioning. Their lack of inhibitory in their hypothalamic functioning leads to their high appetite, which at the end of the day ends up becoming the reason these individuals are overweight.
The method is quite instrumental as it allows researchers to see the brain activity as it unfolds in actions; the view of response is almost immediate and time-bound. When compared to the FMRI, the method gives an excellent temporal resolution in analyzing brain activity. The findings are not based on induced stimuli which at times might be biased but rather makes use of the natural stimuli patients are in constant contact with. Studying brain activity with reference to the day to day interactions with the environment ensures that the treatment that is created is effective. This is because the treatment will be based on actual environmental-based findings. Findings in these methods can be of great help in finding a solution to the health condition in question, which is obesity. Studying patients from natural stimuli is the best way to analyze their appetites and the drive behind their eating habits. While the method might not be effective in determining the exact part of the brain that is bringing the changes that are visible to the researcher, the idea they get from the responses the brain makes with the real environment is enough to be able to analyze the brain and come up with a valid conclusion. With a few brains scans to supplement the lack of knowledge of where exact parts of the memory are responsible would be instrumental in ensuring the results to be compiled are actually legit. With this method, the future of treating obesity is quite clear, and all we can hope for is that with advancements in technology, the method can be enhanced.
Conclusion.
Obesity has become a world problem with regard to the fact that it leads to other diseases such as heart diseases and diabetes. The need to look for a way to ensure that we are fully aware of the causes of obesity has raised the need to study the brain activity with reference to the cognitive behaviours associated with obesity. The use of fMRI clearly shows that the hypothalamus responds quite slowly to food stimulations and therefore, obese individuals are unable to control their appetites and therefore are exposed to secondary obesity due to their eating habits. The lack of control over gut hormones leads to increased appetite. ERP method shows how overweight people have no preferences over the type of food they take high or calorie food to them is no different. This predisposes them to even more serious health issues. The combined efforts of the two methods in finding the right treatment to the condition would be critical in the treatment of obesity. With technological advancements, using the ERP methods to study real-time behaviour and fMRI to determine the parts of the brain responsible for each behaviour will be a key tool in ensuring that the treatment of obesity is achieved. With these few advancements we are sure to totally eliminate the condition globally.
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