Neural correlates of short-term perceptual learning in orientation discrimination indexed by event-related potentials

The current work investigated the neural correlates of visual perceptual learning in grating orientation discrimination by recording event-related potentials (ERPs) from human adults. Subjects were trained with a discrimination task of grating orientation in three consecutive training sessions within 2 h. While reaction times (RTs) were shortened gradually across training sessions, the N1 was decreased and the P2 was increased over the parietal and occipital areas. A broadly distributed P3 was increased along with more practices. In addition, the time course of learning reflected in the P2 and P3 amplitudes was in line with the changes of reaction times and exhibited a stable level during later training. The impli- cations of these results to the neural mechanisms subserving perceptual learning were discussed.     

Involvement of the crebellum in sequential finger movement learning： Evidence from functional magnetic resonance imaging

Whether the cerebellum is involved in voluntary motor learning or motor performance is the subject of a new debate. Using functional magnetic resonance imaging （fMRI）, we examined cerebellar activation in eight voluntecrs before and after an extended period of training. Activation volume on both sides of cerebellum after learning was significantly reduced compared to that before learning even under the same motor frequency. Remarkably, while motor frequency for the training sequence was significantly higher than the control sequence after 41 d of learning, activation in the cerebellum for both sequences, with respect to activation loci and volumes, was very similar. These results suggest that the cerebellum was involved in motor learning but not motor performance. Changes of cerebellar activation from training thus appear to be associated with learning but not with improvement on task performance.     

Revision of “Parahagla lamina” Lin, 1982 and two new species of Aboilus (Orthoptera: Prophalangopsidae) from the EarlyMiddle Jurassic of Northwest China

The Lower and Middle Jurassic insects are rather poorly known from Northwest China. Here we restudy Parahagla lamina Lin, 1982 and transfer it from “Parahagla” to Aboilus Martynov, 1925. On the basis of the female forewing, we described two new species of the EarlyMiddle Jurassic, Aboilus tuzigouensis sp. nov. caome from Badaowan Foramtion at Tuzigou, Kelamayi, Xinjiang, Northwest China and A. jiyuanensis sp. nov. from Ma’ao Group, Jiyuan, Henan Province, Central China. The differences of the new materials from the other known species and their systematic positions are also discussed.     

Revision of “Parahagla lamina” Lin, 1982 and two new species of Aboilus (Orthoptera: Prophalangopsidae) from the EarlyMiddle Jurassic of Northwest China

The Lower and Middle Jurassic insects are rather poorly known from Northwest China. Here we restudy Parahagla lamina Lin, 1982 and transfer it from “Parahagla” to Aboilus Martynov, 1925. On the basis of the female forewing, we described two new species of the EarlyMiddle Jurassic, Aboilus tuzigouensis sp. nov. caome from Badaowan Foramtion at Tuzigou, Kelamayi, Xinjiang, Northwest China and A. jiyuanensis sp. nov. from Ma’ao Group, Jiyuan, Henan Province, Central China. The differences of the new materials from the other known species and their systematic positions are also discussed.