Thu, 21 Aug 2008 06:48:53 BST CiteULike: sensesublime's Yu http://www.citeulike.org/user/sensesublime/author/Yu CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/sensesublime/article/1119147 <i>Neuroreport, Vol. 17, No. 16. (6 November 2006), pp. 1747-1751.</i><br /><br />Previous studies find that the feedback-related negativity in brain potentials is sensitive to the negative outcome of one's own performance. The feedback-related negativity is suggested to reflect the learning processes using feedback about the consequences of recent actions. Learning can also take place when one observes other people's actions and the associated outcomes. We recorded brain potentials while the participant received outcome feedback for their own or for another person's performance in a gambling task. The feedback-related negativity or the feedback-related negativity-like effects were obtained in both situations, suggesting that similar neural mechanisms are involved in evaluating the outcomes of one's own and the other's actions. Thus, the neural processes in learning-by-observation resemble those in learning-by-doing. Brain responses to outcomes of one's own and other's performance in a gambling task. R Yu X Zhou doi:10.1097/01.wnr.0000239960.98813.50 Neuroreport, Vol. 17, No. 16. (6 November 2006), pp. 1747-1751. 2007-02-23T18:17:37-00:00 2006 Neuroreport 0959-4965 17 16 1747 1751 gambling mfn observation http://www.citeulike.org/user/sensesublime/article/1111752 <i>Cereb Cortex, Vol. 7, No. 4. (June 1997), pp. 374-385.</i><br /><br />Changes in cortical activity during working memory tasks were examined with electroencephalograms (EEGs) sampled from 115 channels and spatially sharpened with magnetic resonance imaging (MRI)-based finite element deblurring. Eight subjects performed tasks requiring comparison of each stimulus to a preceding one on verbal or spatial attributes. A frontal midline theta rhythm increased in magnitude with increased memory load. Dipole models localized this signal to the region of the anterior cingulate cortex. A slow (low-frequency), parietocentral, alpha signal decreased with increased working memory load. These signals were insensitive to the type of stimulus attribute being processed. A faster (higher-frequency), occipitoparietal, alpha signal was relatively attenuated in the spatial version of the task, especially over the posterior right hemisphere. Theta and alpha signals increased, and overt performance improved, after practice on the tasks. Increases in theta with both increased task difficulty and with practice suggests that focusing attention required more effort after an extended test session. Decreased alpha in the difficult tasks indicates that this signal is inversely related to the amount of cortical resources allocated to task performance. Practice-related increases in alpha suggest that fewer cortical resources are required after skill development. These results serve: (i) to dissociate the effects of task difficulty and practice; (ii) to differentiate the involvement of posterior cortex in spatial versus verbal tasks; (iii) to localize frontal midline theta to the anteromedial cortex; and (iv) to demonstrate the feasibility of using anatomical MRIs to remove the blurring effect of the skull and scalp from the ongoing EEG. The results are discussed with respect to those obtained in a prior study of transient evoked potentials during working memory. High-resolution EEG mapping of cortical activation related to working memory: effects of task difficulty, type of processing, and practice. A Gevins ME Smith L McEvoy D Yu Cereb Cortex, Vol. 7, No. 4. (June 1997), pp. 374-385. 2007-02-18T20:18:23-00:00 1997 Cereb Cortex 1047-3211 7 4 374 385 alpha eeg effort memory theta