Transcranial Magnetic Stimulation - Dissertation Example

?Discussion This is a dissertation on a Transcranial Magnetic Stimulation (TMS) Study on Intra Variability and Attention Deficit/Hyperactivity Disorder-Related States in Adults. A Transcranial Magnetic Stimulation is a procedure that uses magnetic fields to stimulate the nerve cell located in the brain in order to treat certain neurological and psychiatric disorders (Belmaker, and George, 2007). In this dissertation, the TMS is used to verify whether it has any effect on symptoms of ADHD or not. Discussion: Part 1 (pilot study). 5.1.1. Right Eye Movement (Mu) discussion. The Mu values of the three right eye anti-saccade tests of the first three participants are 5.0, 4.6 and 4.6, 4.0, 4.6 and 4.6 and 4.8, 5.2 and 5.2 respectively. According to the anti-saccade task, the more the errors an individual makes in the task, for example looking towards the target (which in this case was the gray dot) instead of looking at the opposite periphery indicates that the individual has problems with the brain activity hence a disorder (Engle, 2005). The participants were measured at three different times and showed almost stable results This means that the participants produced few errors in the anti-saccade task hence can be said to almost stable in the ADHD symptoms. In the case of the fourth participant, the results were slightly different from the results of the other three participants. According to the Mu values shown by the results in the graph, the participant had 3.0, 2.6, and 1. These are very low and mean that the participant committed very many errors and therefore may has brain neurological problem and may have unstable symptoms of ADHD. 5.1.2. Right Eye Movement (sig) discussion. The right eye movement sig values of the first three participants are 0.4, 0.2, and 0.3. for the first one, 0.4, 0.2 and 0.25 for the second one and 0.2 for the third on the three anti-saccade task. This indicate that the neurons involved in eye movement of the individual are not affected much by the eye movement hence visual response of the individual is not significantly inhibited. Thus, their anti-saccade task performance is stable and there are no ADHD symptoms. The fourth participant had however very different results from the other three participants. The sig value of the fourth participant was 0.8, 2.0 and 3.0. These indicate a very high value. It therefore means that the neurons of the eye movement are affected and they therefore affect the right visual response. The neurons are affected to a very high extent leading to the conclusion that the participant has unstable anti-saccade performance and may have ADHD symptoms. 5.1.3. Left Eye Movement (Mu) discussion. The Mu values of the left eye movement of the first participant were 4.6, 4.4 and 4.8, for the second one, they were 3.7, 3.8, 3.6 and 3.2, 4.0, 3.6 for the third. These indicated stability of the participant’s ADHD symptoms having been measured by the movement of the left eye. Like in the right eye movement, the almost similar Mu values indicate that the participants have fewer errors unlike the individual with more symptoms. Thus, they have stable performance in three anti-saccade tasks. The fourth participant’s Mu results were 3.0, 3.7 and 3.9. This means that there were many errors in the anti-saccade tasks which indicated that the brain activity of that participant was somewhat low and hence the symptoms were more stable but those of the other three anti-saccade performances were not stable. 5.1.4. Left Eye Movement (Sig) discussion. The left eye movement sig values of the first participant were 0.35, 0.32 and 0.17 and the third participant were 0.3, 0.31 and 0.42. This indicates stable visual response and hence the neurons are not affected or they are affected just a little. If the participants have good visual response, it means that the participants have stable symptoms of ADHD. The participant therefore functions like a normal healthy person and their performance in anti-saccade tack are stable. The second and fourth participants had sig values of 0.15, 0.35, 0.7, and 0.63, 0.55 and 0.82 respectively. However, these two participants had different results of the sig values from the other two participants. This difference is attributed to the neurons in the brain. The brain neurons that may have been affected by a disorder in turn affects how the individual will respond to visual stimuli. This is because there is an interconnectedness of the neurons in the brain region. Therefore, the participant committed many errors in response to the gray spot in anti-saccade task, which was considered unstable performance. From the results above, the examiners found that 3 out of 4 (75%) participants have a stable performance in the three anti-saccade task and then have no ADHD symptoms. Consequently, it can be verified that the anti-saccade task design is sufficiently stable by 75% and any defect in its performance is due to other factors such as ADHD symptoms. These results provided confidence to progress to the actual study. 5.2. Discussion part 2: Barkley’s ADHD questionnaire (current symptoms). The Barkley’s ADHD questionnaire used to measure the symptoms of ADHD (Barkley, 2010). in each participants of the main study showed impulsivity was the most common symptoms (4 out of 6 participants) compared to hyperactivity and inattention(3 out of 6 participants). It also indicated that one participant had moderately inattention symptom, two had borderline and the rest had no inattention symptom. Likewise, one participant had borderline-hyperactive symptoms, two had marginal hyperactive and the other three participants had no hyperactive symptoms. Two participants had borderline-impulsivity, two had mild impulsive symptoms and the last two had no impulsivity. Two participants experienced borderline ADHD total symptoms, one had marginal, one had marked ADHD total symptoms and the rest had no ADHD total symptoms. In Sluggish Cognitive Tempo symptoms (SCT), 4 out of 6 participants had no symptoms, one participant had borderline SCT and the last had marginal SCT symptoms. Berkley also indicated the onset age which is necessary for intervention of the participants (Barkley, 2010). In this study the ages of onset for the five participants were before 16 years old and just one participant experienced 19 years old as the age of onset. The use of the questionnaire gathered more information about the participants of the study which can be used to determine the type of intervention for each participant individually according to the density of symptoms (Barkley, 2006). The difference between Berkley’s tests and the anti-saccade tasks is that Berkley measured the observable symptoms of the disorder while anti-saccade and the other test measured brain activity which was not observable hence are more conclusive than the observable ones which may be prone to bias by participants and also the ones analyzing the questionnaires. The above results can be interpreted to show the intra-personal variability in stability of ADHD in as far as the symptoms of the disorder are assessed. Different individuals having the ADHD symptoms may be affected differently and therefore the form of interventions administered to such individuals should also depend with the stability of the symptoms. In addition, the participant in this study had low level of ADHD symptoms thus they are not ADHD sample, and 5 out of 6 participant had ADHD symptoms in their childhood that might be diminished in their adulthood, these results are compatible with the results by Lahey et al. (1999). 5.3. Discussion part 3 Anti-saccade task and theta burst TMS. The left and right eye anti-saccade movement are measured before and after theta burst TMS and also measured when both the real and sham TMS is administered to the participants. In all the scenarios (pre, post1 and post2), the anti-saccade is measured. Comparing the mean and standard deviations, the results indicate a slight increase in the left and right eye movement error in anti-saccade task in both real and sham TMS. This means that administration of the real and sham TMS did not improved the visual response and therefore increased the number of errors committed by the participants when presented with visual stimuli in the anti-saccade task. The possible reason for the same response to real and sham theta burst TMS is due to study sample, the participants are healthy individuals without any significant symptoms associated with the ADHD disorder as it is in the Barkley’s ADHD questionnaire results. The Mauchly’s test of sphericity also indicated that the sphericity support the results above. This is because of the differences between the participants not being very different from one another. This denotes that most of the participants did not have ADHD symptoms and therefore no change expected to take place hence the reasons for the results being non significant. In the multivariate test, the variables in the study (TMS, time point and eye movement direction) were not significant when presented within subjects hence agreeing with the null hypothesis. However, according to the univariate test scores, the time point RT mean is .002, this therefore indicates significance and hence rejection of the null hypothesis. The rejection of the null hypothesis means that there is a significant improvement in the performance of the participants on anti-saccade tasks after the application of the theta-burst TMS. This therefore goes against the results of the multivariate tests of non-significance indicated by the results. The rejection of the null hypothesis may be as a result of the few participants having symptoms of the disorder. 5.4. Discussion part 4 Global Vigor and Affect instrument. In the Global Vigor and Global Affect test, the results elicited showed the difference between presentation of the real and sham TMS. In both the real and sham TMS, the participants GV and GA were recorded. The participants’ GV was high before the real TMS was administered but after the TMS, the GV reduced. According to research findings of Klein et al. (2006), the significant increase in work or memory load, response time and accuracy of patients with ADHD when responding to continuous performance test, a stop signal and go-no go tasks, and N-back tasks were negatively affected, hence continous tests being performed on the participants may have therefore been the cause of such results discussed above. According to the results from the study, there was significance in the GV results which indicate that the null hypothesis was wrong hence should be rejected. These results led to the interpretation that the there was a significant improvement in the performance of the participants on GVA after applying theta-burst TMS. On the other hand, the GA results indicated no significance but this does not change the interpretation because GV measures the energy and alertness of the participant which indicate the symptoms of ADHD of hyperactivity and inattention. This therefore leads to the conclusion that symptoms of ADHD were present though on a low level. Conclusion This study was about a Transcranial Magnetic Stimulation (TMS) Study on Intra-Subject Variability and Attention Deficit/Hyperactivity Disorder-Related States in Adults. The study showed the different results provided by the different measures and tests used as a way of justifying the problem under study and also showing how it may be a problem. It is evident from the results shown above that there are intra-subject differences in the ADHD disorder in terms of onset and severity of the symptoms. The different measures used have shown that subjects vary in their response to variables like TMs, time-point and direction of eye movement which indicate the severity of the disorder or even the presence of the disorder. The limitation of this study was that the participants were subjected to numerous tests in a short span of time and it may have therefore led to incorrect results being observed. The time given for relaxation was only one week hence not enough to recover from the previous tests. The other limitation was using many participants with no symptoms of ADHD hence affected the ability of the results to be generalized. Further studies should be carried out using more participants who have more symptoms of ADHD so that most of the results that appeared insignificant or whose significance was minimal like in the anti-saccade test can have more pronounced significance. In future also, there should be more time break given in between tests to allow participants time to recover from previous tests hence reliability of the next tests to be performed. References 2011. Web. http://jn.physiology.org/content/63/3/523.abstract. Retrieved 12th December. Aitken, M. and Cardinal, R. (2006). ANOVA for the behavioural sciences researcher. London: Routledge. Barkley, R. (2010). ADHD in Adults. London: Jones &Barlett Learning. Belmaker, R.and George, M. (2007). Transcranial magnetic stimulation in clinical psychiatry. Virginia: American Psychiatry Pub. Engle, R. (2005). Cognitive limitations in aging and psychopathology. New York: Cambridge University Press. Field, A. (2009). Discovering statistics using SPSS. London: Sage Publications Ltd. Fischer, M et al. (2010). ADHD in adults: What Science says. New York: Guilford Press. Handy, T. (2009). Brain signal analysis: advances in neuroelectric and neuromagnetic methods. Massachusetts: MIT Press. Hunter, W. (2003). Psychological abstracts, volume 90. New York: American Psychological Association. Klein, G. et al. (2006). Working minds: a practitioner’s guide to cognitive task analysis. Massachusetts: MIT Press. Padberg, F. and Marcolin, M. (2007). Transcranial brain stimulation for treatment of psychiatric disorders. 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