The primary goal of this study was to assess the connection and causation between the exposure to stress factors in female patients and the speed of brain activation in response to negative factors. The researchers compared the effects of negative factors on the level of brain activation between patients with and those without stressful life experiences (SLEs) prior to the onset of their depression. Their research revealed that this was still a grey area that needed further investigation to determine whether individuals falling into these two groups respond differently to negative stimuli based on their prior experiences.
Data obtained from the MRI system was then analyzed using SPSS 19.0 software where a P value<0.05 is considered statistically significant.The results of the analysis revealed that when stimulated with negative emotional pictures, female depressed patients with SLEs had a significantly higher activation of particular brain regions belonging to the area of the prefrontal lobe than those with no SLEs (Li et al., 2015). The outcome of this study led the researchers to make a conclusion that patients who have had SLEs have a higher response rate to negative stimuli than those who have not gone through the same. Their experiences remain imprinted in the brain and every time something triggers the memory, such individuals are likely to respond quicker and to a greater extent to the stimuli than those who do not have such memories.
General and Psychological Analysis of the Study
The investigation revealed that there are limited scholarly researches which compare brain activation to stimuli between patients with stressful life experiences and those who have not had such experiences prior to their first major episodes of depression. The few studies that exist compare such a response between patients with depression and those who lack the condition. As such, this was a pioneer research in this field. It was important to ensure that their study met specific assessment criteria that would enable other scholars to trust its findings and use it as a basis upon which they could develop further studies.
The Aims and Key Aspects of the Investigation
The main objective of the study concerned testing the hypothesis of whether being drug-naïve served as an important factor in brain activation toward the onset of depression for female patients when exposed to respective stimuli. In their review of the literature, the authors of this article noted that there is limited research in this field of study. One of the key aspects of their study was to establish if SLEs had any significant impact on the manner in which a patient responded to a negative stimulus. Through this investigation, they wanted to determine ways of protecting these patients with major depressive episodes. It was apparent that patients who have not had SLEs have a better capacity to deal with negative stimulus than their colleagues who went through such experiences (Szucs & Ioannidis, 2017). Their findings helped in ensuring that when handling patients suffering from major depression and who have had SLEs, stressful experiences are avoided as much as possible. Such stimuli worsen their condition because the brain tends to respond to a greater extent compared with their colleagues in the control group.
The Hypotheses and Their Justification
The hypothesis established that the presence of stress in female patients’ lives affected the extent and speed of brain activation. The researchers believed, through their preliminary investigations, that patients with SLEs are more sensitive to negative stimuli than their colleagues whose depression was caused by other factors. The scholars were able to justify their hypothesis. A study by Pfeifer and Weston (2020) showed that about 90% of those who suffer from major depressive episodes identify stress as a major factor that contributed to their condition. As such, anything that reminds them of the stressful situation will worsen their condition. Their brain, as indicated in the MRI test, responds faster when exposed to these negative stimuli. On the other hand, those who have not had SLEs take time to respond to such stimuli, and the response is not as pronounced as that of their colleges in the experimental group.
The Appropriateness of the Experimental Design, Participants, Tasks and Stimuli
The analysis of the article shows that the experimental design, participants, tasks, and stimuli were appropriately selected for the best outcome of this study. The experimental design of exposing participants to a negative stimuli and then assessing the response of different parts of the brain using an MRI scan was an effective scientific approach of assessing the impact. Participants were advised to express their feelings freely without suppressing them. Instead of asking them how they felt, a process that is prone to data distortion, the researchers used a scientific method of actually measuring the response of the brain through scan (Roy & Kessels, 2019). Participants did not have to explain their feelings because the outcome was visible to the investigators.
The strict selection of the participants, as they were drug-naïve patients with first major depressive episodes, was also appropriate in ensuring that other external factors, outside the scope of this study, do not significantly influence the outcome of the investigation (Pinti et al., 2020). The task given to the participants, of observing the negative pictures and responding to them accordingly, was also another appropriate way of conducting this investigation. The researchers also selected simple but highly appropriate stimuli. Pictures tend to bring emotions and it is an easy way of eliciting response from the brain. Thus, the overall design of the research in question appears to be rather reasonable given the goals of the study and the methods chosen to achieve them.
The Correctness of the Behavioral Data Analysis and Interpretation
The Life Event Scale (LES) was used to collect quantitative data for the analysis, which indicates that the premises for the behavioral data analysis were set at the required quality level. More specifically, the study used a two-sample t-test, which is a method applied to test whether the unknown population means of two groups are equal or not. As the patients were divided into the required two categories, the impact of the SLEs on patients was quantitatively assessed using the LES (Li et al., 2015). By using the t-tests as the key instrument in conducting this analysis, the study determined the disparity in brain activation regions between the examined patients.
The interpretation of the data at hand was implemented with due effectiveness and meticulousness. The application of the two-sample test to evaluate the quality and extent of the data under analysis has allowed for a more a more accurate data analysis, leading to a more effective interpretation of the key outcomes of the study. However, the data received are not sufficient to explain the neural mechanisms of SLEs concerning the onset of a major depressive episode because of the restricted set of healthy controls. Moreover, the data cannot illustrate the effect of SLEs on the emergence of depressive disorder. With that said, the data can be considered correct only in terms of the female patients group experiencing a major depressive disorder.
This research needs to be followed by a long-term study, including a large sample size, uniting imaging and genetic techniques to better define the pathological mechanisms of SLEs on the beginning of depression. Also, a longer period for the investigation is crucial to confirm the potential bipolar disorder symptoms for the correct data interpretation. In addition, the long-term follow-up research is critical to examine the connection between the therapeutic impact and early alterations in functional brain imaging outcomes regarding the two groups involved. For the general optimization of clinical therapy for depression and correct data results, it is necessary to analyze predictive functional neuroimaging markers (Li et al., 2015). To sum up, the selection of the assessment tools and the choice of data collection have defied the outcomes of the analysis to a certain degree.
The Effectiveness of the fMRI Parameters Chosen Given the Aim and Design of the Study
The pilot study aimed at investigating the particular functional deviations between the two groups under the study. It serves as the groundwork for further large sample long-term research featuring an effective way of using the fMRI parameters for accurate information and data assessment (Li et al., 2015). It is crucial that the research applied T1WI and T2WI sequences to eliminate subjects with severe brain illnesses, given that T1-weighted and T2-weighted spin-echo pulse sequences are usually included in all brain protocols. A common fMRI experiment includes each image to be acquired as several slices with thickness ~ 5 mm, as was applied in this pilot study (5.5 mm), and in-plane resolution of 3×3 mm for a field of view of 192×192 mm.
A single fMRI image complies with the typical dimensions of 64x64x21 mm. However, the voxel size applied (3 – 3.1 mm) is smaller than the average size used for fMRI, which contains fewer neurons, less blood flow, and has a lowered signal. Smaller voxels also imply a more extended scanning period, leading to the loss of the magnetization signal. In this study, the TR and TE differ from the most common MRI sequences. Also, the research used the partial flip angle (90º), which can enhance the signal-to-noise ratio in fast body imaging. However, the repetition time (RT) set at 350 ms could be considered insufficient, given that the traditional fMRI setting requires the 60 ms RT to obtain the images with the highest resolution (Roy and Kessels, 2019). The study has been customized to meet the goals and objectives specific to the research. The parameters of this research helped conclude that drug-naïve female patients who addressed SLEs before the depression episode had enhanced activation of certain brain regions concerning their emotional capacity, memory, assessment, control, and expression.
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