Cortical areas involved in object, background, and object-background processing revealed with functional magnetic resonance adaptation

Telah dilakukan penelitian terhadap modifikasi kristal Tolbutamida untuk memperoleh suatu bentuk kristal dengan kelarutan tertinggi atau lebih dikenal struktur kristal aktif. Modifikasi kristal diperoleh dengan menggunakan bermacam macam pelarut (polar non polar) dan bervariasinya kecepatan pendinginan. Analisa kristal didasarkan pada spektra infra merah, analisa termal (differential thermal Analysis dan Thermo gravi metri analysis). difraksi sinar-X dan kelarutan

Age-Related Neural Dedifferentiation in the Motor System

Recent neuroimaging studies using multi-voxel pattern analysis (MVPA) show that distributed patterns of brain activation elicited by different visual stimuli are less distinctive in older adults than in young adults. However, less is known about the effects of aging on the neural representation of movement. The present study used MVPA to compare the distinctiveness of motor representations in young and older adults. We also investigated the contributions of brain structure to age differences in the distinctiveness of motor representations. We found that neural distinctiveness was reduced in older adults throughout the motor control network. Although aging was also associated with decreased gray matter volume in these regions, age differences in motor distinctiveness remained significant after controlling for gray matter volume. Our results suggest that age-related neural dedifferentiation is not restricted to sensory perception and is instead a more general feature of the aging brain

Whole-brain searchlight analysis of age differences in motor distinctiveness.

<p>Whole-brain searchlight analysis of age differences in motor distinctiveness.</p

Sustained happiness? Lack of repetition suppression in right-ventral visual cortex for happy faces

Emotional stimuli have been shown to preferentially engage initial attention but their sustained effects on neural processing remain largely unknown. The present study evaluated whether emotional faces engage sustained neural processing by examining the attenuation of neural repetition suppression to repeated emotional faces. Repetition suppression of neural function refers to the general reduction of neural activity when processing a repeated stimulus. Preferential processing of emotional face stimuli, however, should elicit sustained neural processing such that repetition suppression to repeated emotional faces is attenuated relative to faces with no emotional content. We measured the reduction of functional magnetic resonance imaging signals associated with immediate repetition of neutral, angry and happy faces. Whereas neutral faces elicited the greatest suppression in ventral visual cortex, followed by angry faces, repetition suppression was the most attenuated for happy faces. Indeed, happy faces showed almost no repetition suppression in part of the right-inferior occipital and fusiform gyri, which play an important role in face-identity processing. Our findings suggest that happy faces are associated with sustained visual encoding of face identity and thereby assist in the formation of more elaborate representations of the faces, congruent with findings in the behavioral literature

Whole-brain searchlight analysis of the distinctiveness of motor representations, collapsing across age.

<p>Distributed patterns of activation in primary motor cortex, pre-supplementary motor area (left panel; z = 56) cerebellum (right panel; y =  −52) reliably distinguished between left- and right-hand finger tapping. Coordinates are reported in MNI space.</p