Different neuroplasticity for task targets and distractors.
Different neuroplasticity for task targets and distractors.
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DOI：
10.1371/journal.pone.0015342
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发表时间：
2011-01-31
期刊：
影响因子：
3.7
通讯作者：
Blake DT
中科院分区：
文献类型：
--
作者：
Spingath EY;Kang HS;Plummer T;Blake DT
成人学习诱导的感觉皮层可塑性导致具有与任务最相关的信息的神经元的动作电位速率增强，或者那些对一种感觉刺激反应强烈但对其比较刺激反应较弱的神经元。目前的理论认为，这种可塑性是由来自神经调节核团的奖赏信号增强靶刺激诱发的活动引起的。先前的工作已经发现证据表明，非选择性增强的神经反应，抑制任务干扰的反应，但在这些影响之间的差异检测和歧视没有直接测试。使用皮质植入物，我们定义生理反应猕猴体感皮层在串行，匹配，检测和歧视的任务。在检测学习过程中观察到神经反应性的非选择性增加。抑制任务干扰的反应，观察歧视学习过程中，这种抑制是特定的皮质位置，采样的任务干扰学习前的反应。感受野大小的变化被测量为对恒定幅度刺激有显著反应的皮肤面积，并且这些面积变化代替了反应性的变化。从检测学习之前，直到歧视学习后，持久的变化是选择性抑制的皮质位置响应任务干扰，和非选择性增强的反应在皮质位置选择性的目标和控制皮肤网站。在以前的研究中观察到的可塑性效应的比较表明，非选择性反应增强和选择性抑制足以解释已知的可塑性现象，在简单的空间任务。这项工作表明，一个简单的空间检测和歧视的任务，在初级感觉皮层的任务目标和干扰的差异性反应产生的非选择性增加反应在一个广泛的皮质轨迹，包括代表的任务目标，和选择性抑制的反应任务干扰在这个轨迹。
Adult learning-induced sensory cortex plasticity results in enhanced action potential rates in neurons that have the most relevant information for the task, or those that respond strongly to one sensory stimulus but weakly to its comparison stimulus. Current theories suggest this plasticity is caused when target stimulus evoked activity is enhanced by reward signals from neuromodulatory nuclei. Prior work has found evidence suggestive of nonselective enhancement of neural responses, and suppression of responses to task distractors, but the differences in these effects between detection and discrimination have not been directly tested. Using cortical implants, we defined physiological responses in macaque somatosensory cortex during serial, matched, detection and discrimination tasks. Nonselective increases in neural responsiveness were observed during detection learning. Suppression of responses to task distractors was observed during discrimination learning, and this suppression was specific to cortical locations that sampled responses to the task distractor before learning. Changes in receptive field size were measured as the area of skin that had a significant response to a constant magnitude stimulus, and these areal changes paralleled changes in responsiveness. From before detection learning until after discrimination learning, the enduring changes were selective suppression of cortical locations responsive to task distractors, and nonselective enhancement of responsiveness at cortical locations selective for target and control skin sites. A comparison of observations in prior studies with the observed plasticity effects suggests that the non-selective response enhancement and selective suppression suffice to explain known plasticity phenomena in simple spatial tasks. This work suggests that differential responsiveness to task targets and distractors in primary sensory cortex for a simple spatial detection and discrimination task arise from nonselective increases in response over a broad cortical locus that includes the representation of the task target, and selective suppression of responses to the task distractor within this locus.
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影响因子：
2.5
作者：
Blake, DT;Strata, F;Merzenich, MM
通讯作者：
Merzenich, MM
DOI：
10.1073/pnas.092278099
发表时间：
2002-07-23
影响因子：
11.1
作者：
Blake, DT;Strata, F;Merzenich, MM
通讯作者：
Merzenich, MM
影响因子：
56.9
作者：
Kilgard, MP;Merzenich, MM
通讯作者：
Merzenich, MM
影响因子：
1.9
作者：
Britten, KH;Newsome, WT;Movshon, JA
通讯作者：
Movshon, JA
影响因子：
5.3
作者：
Bender, KJ;Allen, CB;Feldman, DE
通讯作者：
Feldman, DE