ABSTRACT
It is not clearly known as to why some people identify camouflaged objects with ease compared with others. The literature suggests that Field-Independent individuals detect camouflaged object better than their Field-Dependent counterparts, without having evidence at the neural activation level. A paradigm was designed to obtain neural correlates of camouflage detection, with real-life photographs, using functional magnetic resonance imaging. Twenty-three healthy human subjects were stratified as Field-Independent (FI) and Field-Dependent (FD), with Witkin’s Embedded Figure Test. FIs performed better than FDs (marginal significance; p=0.054) during camouflage detection task. fMRI revealed differential activation pattern between FI and FD subjects for this task. One sample T-test showed greater activation in terms of cluster size in FDs, whereas FIs showed additional areas for the same task. On direct comparison of the two groups, FI subjects showed additional activation in parts of primary visual cortex, thalamus, cerebellum, inferior and middle frontal gyrus. Conversely, FDs showed greater activation in inferior frontal gyrus, precentral gyrus, putamen, caudate nucleus and superior parietal lobule as compared to FIs. The results give preliminary evidence to the differential neural activation underlying the variances in cognitive styles of the two groups.
ABSTRACT
Empathy deficit is a core feature of schizophrenia which may lead to social dysfunction. The present study was carried out to investigate functional and structural abnormalities associated with empathy in patients with schizophrenia using functional magnetic resonance imaging (fMRI) and voxel-based morphometry (VBM). A sample of 14 schizophrenia patients and 14 healthy control subjects matched for age, sex and education were examined with structural highresolution T1-weighted MRI; fMRI images were obtained during empathy task in the same session. The analysis was carried out using SPM8 software. On behavioural assessment, schizophrenic patients (83.00±29.04) showed less scores for sadness compared to healthy controls (128.70±22.26) (p<0.001). fMRI results also showed reduced clusters of activation in the bilateral fusiform gyrus, left lingual gyrus, left middle and inferior occipital gyrus in schizophrenic subjects as compared to controls during empathy task. In the same brain areas, VBM results also showed reduced grey and white matter volumes. The present study provides an evidence for an association between structural alterations and disturbed functional brain activation during empathy task in persons affected with schizophrenia. These findings suggest a biological basis for social cognition deficits in schizophrenics.
ABSTRACT
Inflammatory pseudo-tumor of spleen, a benign reactive lesion of unknown etiology and pathogenesis, is extremely rare with isolated case reports in literature. These are usually misdiagnosed preoperatively, both clinically and radiologically; metastasis or lymphoproliferative disorders with pathological studies allow reliable diagnosis of the disease. We report the unusual occurrence of this lesion in the spleen.