Hodzic Amra, Veit Ralf, Karim Ahmed A, Erb Michael, Godde Ben
Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, D-72074 Tübingen, Germany.
J Neurosci. 2004 Jan 14;24(2):442-6. doi: 10.1523/JNEUROSCI.3731-03.2004.
Perceptual learning can be induced by passive tactile coactivation without attention or reinforcement. We used functional MRI (fMRI) and psychophysics to investigate in detail the specificity of this type of learning for different tactile discrimination tasks and the underlying cortical reorganization. We found that a few hours of Hebbian coactivation evoked a significant increase of primary (SI) and secondary (SII) somatosensory cortical areas representing the stimulated body parts. The amount of plastic changes was strongly correlated with improvement in spatial discrimination performance. However, in the same subjects, frequency discrimination was impaired after coactivation, indicating that even maladaptive processes can be induced by intense passive sensory stimulation.
无需注意力或强化,通过被动触觉共激活即可诱导知觉学习。我们使用功能磁共振成像(fMRI)和心理物理学方法,详细研究了这种学习类型对不同触觉辨别任务的特异性以及潜在的皮质重组。我们发现,几小时的赫布式共激活会引起代表受刺激身体部位的初级(SI)和次级(SII)体感皮层区域显著增加。可塑性变化的程度与空间辨别性能的改善密切相关。然而,在同一受试者中,共激活后频率辨别能力受损,这表明即使是强烈的被动感觉刺激也可能诱发适应不良的过程。