Transcranial Magnetic Stimulation over Posterior Parietal Cortex Disrupts Transsaccadic Memory of Multiple Objects
Transcranial Magnetic Stimulation over Posterior Parietal Cortex Disrupts Transsaccadic Memory of Multiple Objects
复制标题
对后顶叶皮层的经颅磁刺激会破坏多个物体的扫视记忆
作者：
S. L. Prime;M. Vesia;J. Crawford
后顶叶皮层（PPC）在扫视过程中眼球和手臂运动目标的空间更新中起作用，但其在知觉记忆更新中的作用尚不清楚。我们之前报道过，跨跳眼记忆具有在单个注视（注视任务）或不同注视（扫视任务）之间存储三到四个Gabor斑块方向的能力。在这里，我们测试了8个被试的PPC在跨跳记忆中的作用，方法是同时在几个控制部位的左右PPC上施加单脉冲经颅磁刺激（TMS），并将其与没有经颅磁刺激的行为对照组进行比较。在颅磁刺激试验中，我们在扫视前后的三个不同时间间隔中的一个随机发送脉冲，或者在注视任务的等效时间发送脉冲。对照组证实，受试者正常情况下至少能保留三个视觉特征。经颅磁刺激对左PPC和对照部位的表现没有显著影响。然而，经颅磁刺激右脑PPC会破坏两项任务中的记忆表现。这种经颅磁刺激诱导的效应在扫视任务中最具破坏性，特别是当刺激与扫视时间更接近时。在这里，比较动前和动后特征的能力被减少到一个对象，正如预期的那样，如果记忆的空间方面被破坏了。这一发现表明右脑PPC在视觉特征跨跳记忆的空间加工中起作用。我们认为这一过程使用了与扫视相关的反馈信号，类似于在空间更新中观察到的反馈信号。
The posterior parietal cortex (PPC) plays a role in spatial updating of goals for eye and arm movements across saccades, but less is known about its role in updating perceptual memory. We reported previously that transsaccadic memory has a capacity for storing the orientations of three to four Gabor patches either within a single fixation (fixation task) or between separate fixations (saccade task). Here, we tested the role of the PPC in transsaccadic memory in eight subjects by simultaneously applying single-pulse transcranial magnetic stimulation (TMS) over the right and left PPC, over several control sites, and comparing these to behavioral controls with no TMS. In TMS trials, we randomly delivered pulses at one of three different time intervals around the time of the saccade, or at an equivalent time in the fixation task. Controls confirmed that subjects could normally retain at least three visual features. TMS over the left PPC and a control site had no significant effect on this performance. However, TMS over the right PPC disrupted memory performance in both tasks. This TMS-induced effect was most disruptive in the saccade task, in particular when stimulation coincided more closely with saccade timing. Here, the capacity to compare presaccadic and postsaccadic features was reduced to one object, as expected if the spatial aspect of memory was disrupted. This finding suggests that right PPC plays a role in the spatial processing involved in transsaccadic memory of visual features. We propose that this process uses saccade-related feedback signals similar to those observed in spatial updating.
登录
查看更多内容
DOI：
10.1073/pnas.0601813103
发表时间：
2006-07-25
影响因子：
11.1
作者：
Shomstein, Sarah;Behrmann, Marlene
通讯作者：
Behrmann, Marlene
DOI：
10.1098/rstb.1999.0476
发表时间：
1999-07-29
影响因子：
6.3
作者：
Pascual-Leone, A;Bartres-Faz, D;Keenan, JP
通讯作者：
Keenan, JP
抓住物体的把手：认知和行动之间必要的相互作用。
DOI：
10.1037//0096-1523.27.1.218
发表时间：
2001
期刊：
Journal of experimental psychology. Human perception and performance
影响因子：
--
作者：
Creem,SH;Proffitt,DR
通讯作者：
Proffitt,DR
影响因子：
56.9
作者：
ANDERSEN, RA;ESSICK, GK;SIEGEL, RM
通讯作者：
SIEGEL, RM
影响因子：
2.5
作者：
Chafee, MV;Goldman-Rakic, PS
通讯作者：
Goldman-Rakic, PS