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      Schizophrenia is a severe and complex mental illness that includes a variety of symptoms affecting person’s cognitive abilities and emotional responses (National Institute of Mental Health, 2016). Among “positive” symptoms of Schizophrenia are those that have an “acquired” nature, like hallucinations, delusions, thought disorders, movement disorders (National Institute of Mental Health, 2016). “Negative” Schizophrenic symptoms include capabilities that have been “lost” from individual’s personality, like emotional flat effect, anhedonia, severe apathy, social withdrawal, lack of drive or interest (National Institute of Mental Health, 2016).
      Bipolar disorder (BPD) is a mental health condition that causes extreme mood swing that include emotional highs, like mania or hypomania, and emotional lows, such as depression (Mayo Clinic, 2017). Manic phase symptoms include mood and behavioral changes, for example, having an overly silly or joyful mood, talking fast about many different things, having a short temper to extreme irritability, having high levels of energy despite not getting an adequate amount of sleep, tendency to make irrational and risky decisions, experience “very fast” thoughts (National Institute of Mental Health, 2016). Depressive phase may include feeling hopeless and sad, not having any energy and significantly reduced energy levels, trouble concentration on things, forgetfulness, the feeling of emptiness, change in eating and sleeping patterns, thinking about death or contemplating a suicide (National Institute of Mental Health, 2016). 
      In the case of both mental illnesses the impairment of multiple and highly critical brain circuits that relay information through the thalamus is involved (Byne et al. 2001). Abnormal activation of somatosensory cortex, the auditory, or the visual cortex may be attributed to synaptic degeneration within the thalamic relay nuclei (VPL, LGN, MGN) and result in the appearance of various types of hallucinations observed in Schizophrenia (Nolte, 2009). Parts of the motor and limbic system also relay their information via thalamus (motor: VA, VL; limbic system: Anterior), thus, any abnormalities within those nuclei may account for movement and thought disorders, such as repeated movements, anger outburst, agitation, fear, inability to process emotion and regulate a behavior (Nolte, 2009). Impairments of the DM nucleus may result in disrupted function of the prefrontal cortex, which may be linked to the tendencies towards dangerous and risky behaviors during the manic phase in BPD, as that brain region regulates higher order thinking and executive order making, while in Schizophrenia, it may attribute to the attention deficit, executive function deficit, lack of strategic planning (Nolte, 2009). 
      The aim of this study was to look at the set of pediatric MRI data acquired from the subjects with early onset of Schizophrenia, BPD with psychosis, BPD without psychosis, and healthy controls (HC), and to measure the cerebrum and thalamic volumes and to note significant volumetric differences in those structures based on the type of the subject’s diagnosis. Prior neuroimaging study performed by Frazier et al. (2007) resulted in significant volumetric difference in the thalamus, particularly in subjects with Schizophrenia. Frazier et al. (2007) also demonstrated a significant effect of sex on the total cerebral volume, where both BPD groups (with or without psychosis) had a significantly smaller cerebral volumes as compared to HC, particularly female BPD groups displayed the smallest cerebral volumes as compared to HC. We using a different method in analyzing the same data set, but we are expected to observe the same results in regards to cerebrum and thalamic volumes as did Frazier et al. (2007). 

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     103 subjects included 57 males and 46 females, aged 4-17, made up four diagnostic categories: Bipolar Disorder with Psychosis (N=19), Bipolar Disorder without Psychosis (N=35), Schizophrenia Spectrum (N=20), and Healthy Controls (N=29) (Kennedy et al. 2011). 
      The two independent variables in this study are sex (male and female) and subject diagnosis (BPD with Psychosis, BPD without Psychosis, Schizophrenia, and Healthy Controls). We have two dependent variables in this study: cerebral volume and thalamic volume. For the first dependent variable – cerebrum volume – we used the Anova test to determine the differences among means between subject diagnosis and sex. For the second dependent variable – thalamus volume – we used the Anova with covariants test (Ancova) to control for different ages and brain sizes. 
     Pediatric brain imaging data was acquired on 1.5 Tesla General Electric Sigma Scanner (Kennedy et al. 2011). Structural imaging was done to obtain 124 1.5 mm thick coronal slices, using 10 ms RT and 3 ms TE (Kennedy et al. 2011). 
     The three most common MRI sequences used in tests and diagnostics are T1 weighted, T2 weighted, and T2 Flair according to Preston (2006). T1 weighted MRI is used to analyze anatomical structures and has short TR and short TE, CSF appears dark on T1 weighted MRI, while T2 weighted MRI is obtained using longer TR and TE and will result in bright CSF on the scans, T2 weighted MRI is a good tool for tracking fluids (Preston 2006). T2 Flair is similar to T2 weighted MRI but it implements very long TR and TE, thus normal CSF is weakened and appears dark on the scans while pathologies come into view as brightnesses on the scan (Preston 2006). 
      For image analysis we used FSL software which allowed us to observe the brain in various planes and dimensions, segment cerebrum and thalamus, and to calculate the total volumes of these structures (FMRIB Software Library, 2017). In FSLView we were able to view subjects’ original MRI scans, while FSL BET enabled us to view the brain without any external structures such as meninges, skull, eye balls, etc. FSL First allowed us to segment aspects of the brain that we are studying and FSL Stats gave us the volumetric measurements of cerebrum and thalamus in mm3.  
      Upon completing one-way ANOVA we were able to obtain a significant effect of sex on the cerebrum volume: F (1, 95) = 25.505, p < 0.001, and ?2 = 0.183 (See Figure 1). Similarly, we found a significant main effect of diagnostic category on cerebrum volume: F (3, 95) = 3.312, p = 0.023, and ?2 = 0.071 (See Figure 1). Additionally, there has been shown a significant sex by diagnostic category interaction: F(3, 95) = 2.958, p = 0.036, add the ?2 = 0.064 (See Figure 1). The post hoc test did not yield any significant differences between the specific groups in our study with p > 0.054 despite a statistically significant one-way ANOVA (See Figure 1).
      Repeated measures ANOVA for the within subjects looked at the measures of thalamic volumes that were taken from within the subject, thus left and right side, and did not determine any significant difference across the diagnostic groups: p > 0.226 (See Table 2). Between subjects ANCOVA test asked if the subjects’ average thalamic volumes are different between the diagnostic groups, and the test did show a significant effect of sex on the average thalamic volume: F(1, 93) = 5.441, p = 0.022, add the ?2 = 0.033 (See Figure 2). There has also been shown a significant effect of age on the average thalamic volume: F(1, 93) = 14.312, p < 0.001, add the ?2 = 0.088 and a significant effect of total cerebral volume on the average thalamic volume: F(1, 93) = 40.204, p< 0.001, add the ?2 = 0.247 (See Figure 2).    Discussion        Our study showed a significant effect of sex on the cerebrum volume, with males having larger cerebrum values across all categories, additionally, both BPD groups displayed the smallest cerebrum volumes as compared to HC. These results confirmed the predictions we made in the beginning of our study and we were able to obtain the same results as Frazier et al. (2007). For the thalamic volume we were able to detect only a significant effect of sex, age, and the total cerebrum volume between the subjects, however, there was no significant effect of subject diagnosis on the average thalamic volume, as we predicted in the beginning of our study. These results differed from ones obtained by Frazier et al. (2007) and a different analytical tool that was implemented in our study can be accounted for such difference.       Based on the data we obtained, it can be concluded that decreased cerebrum value can be accounted for symptoms present in BPD patients (with or without psychosis). Although, the total thalamic volume did not show any significant variability across diagnostic groups it might be useful to conduct a future study where we can segment thalamic nuclei and analyze for any volumetric differences between subject categories, since degeneration of a particular nuclei can not be detected if only measuring for overall thalamic volume.  References        FMRIB Software Library (2017) Retrieved January 23, 2018 from       Mayo Clinic (2017). Bipolar Disorder. Retrieved January 23, 2018, from       National Institute of Mental Health (2016). Bipolar Disorder. Retrieved January 23, 2018, from      National Institute of Mental Health (2016). Schizophrenia. Retrieved January 23, 2018, from       Preston D. C. (2006). Magnetic Resonance Imaging (MRI) of the Brain and Spine: Basics. Retrieved January 23, 2018 from       Wanderah, T. W., & Gould D. J. (2009). The Human Brain: An Introduction To Its Functional Anatomy. 7th edition. E-book. Retrieved from

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