Observed, executed, and imagined action representations can be decoded from ventral and dorsal areas

Previous functional magnetic resonance imaging (fMRI) research on action observation has emphasized the role of putative mirror neuron areas such as Broca's area, ventral premotor cortex, and the inferior parietal lobule. However, recent evidence suggests action observation involves many distributed cortical regions, including dorsal premotor and superior parietal cortex. How these different regions relate to traditional mirror neuron areas, and whether traditional mirror neuron areas play a special role in action representation, is unclear. Here we use multi-voxel pattern analysis (MVPA) to show that action representations, including observation, imagery, and execution of reaching movements: (1) are distributed across both dorsal (superior) and ventral (inferior) premotor and parietal areas; (2) can be decoded from areas that are jointly activated by observation, execution, and imagery of reaching movements, even in cases of equal-amplitude blood oxygen level-dependent (BOLD) responses; and (3) can be equally accurately classified from either posterior parietal or frontal (premotor and inferior frontal) regions. These results challenge the presumed dominance of traditional mirror neuron areas such as Broca's area in action observation and action representation more generally. Unlike traditional univariate fMRI analyses, MVPA was able to discriminate between imagined and observed movements from previously indistinguishable BOLD activations in commonly activated regions, suggesting finer-grained distributed patterns of activation

An interference account of cue-independent forgetting in the no-think paradigm

Memory suppression is investigated with the no-think paradigm, which produces forgetting following repeated practice of not thinking about a memory [Anderson MC, Green C (2001) Nature 410:366–369]. Because the forgotten item is not retrieved even when tested with an independent, semantically related cue, it has been assumed that this forgetting is due to an inhibition process. However, this conclusion is based on a single stage to recall, whereas global memory models, which produce forgetting through a process of interference, include both a sampling and a recovery stage to recall. By assuming that interference exists during recovery, these models can explain cue-independent forgetting. We tested several predictions of this interference explanation of cue-independent forgetting by modifying the think/no-think paradigm. We added a condition where participants quickly pressed enter rather than not thinking. We also manipulated initial memory strength and tested recognition memory. Most importantly, learning to quickly press enter produced as much cue-independent forgetting as no-think instructions. Demonstrating the adequacy of two-stage recall, a simple computational model (SAM-RI) simultaneously captured the original cue, independent cue, and recognition results

A three base pair gene variation within the distal 5'-flanking region of the interleukin-10 (IL-10) gene is related to the in vitro IL-10 production capacity of lipopolysaccharide-stimulated peripheral blood mononuclear cells.

Item does not contain fulltextInterleukin-10 (IL-10) is an important multifunctional immunmodulator. There is evidence that IL-10 secretion is associated with certain genetic elements of the proximal IL-10 gene 5'-flanking region. The allelic and genotypic comparison of IL-10 expression by lipopolysaccharide (LPS)- stimulated leukocytes (PBMC) with a recently discovered distal "indel" DNA-sequence variation at - 7400 bp revealed significant inter-individual differences in the IL-10 in vitro production capacity. Homozygotes lacking the three base pairs "GGA" (- 7400del) at this gene locus are characterised by high expression of IL-10 with a median of 1690pg/ml (P <or=0.009). The allelic comparison supports this finding (P <or=0.002). Further analysis of the haplotype -7400/- 1087 showed that homozygotes for - 7400del/- 1087G may be classified as very strong IL-10 responders with a median IL-10 secretion of 2378 pg/ml (P <or=0.025). When leukocytes were stimulated in vitro by dibutyryl-cAMP or infected with Epstein-Barr virus no significant inter-individual differences between the - 7400indel alleles or genotypes and the IL-10 in vitro production capacity were observed. Our findings further the understanding of the complexity of IL-10 gene regulation in relation to defined regulatory gene variations

Automatic affective dynamics: An activation–habituation model of affective assimilation and contrast

Abstract. Our modeling approach seeks to better understand the computational dynamics of the affective and cognitive systems. One experimental phenomenon open to such dynamical analysis is &quot;affective priming &quot;-- or the influence of a prior stimulus on subsequent affective processing. In this type of procedure, ‘assimilation priming ’ refers to when the response to the target is biased in favor of the prime, such as with brief or minimally attended primes. However, following long durations or highly attended primes, the response to the target is often biased against the prime, which is termed ‘contrast priming’. We present a neural dynamics model of affective priming in which this transition from assimilation to contrast occurs automatically as a result of habituation. Unlike response strategies, this transition is predicted to rise and fall in a gradual nonlinear manner as a function of prime duration. We confirmed this prediction with a speeded affect judgment task that manipulated the exposure duration of valenced images.