Domenici Nicola, Tonelli Alessia, Gori Monica
Unit for Visually Impaired People (U-VIP).
J Exp Psychol Gen. 2022 Dec;151(12):3134-3143. doi: 10.1037/xge0001252. Epub 2022 Jun 13.
Sensory adaptation is a feature-specific modulation of neural responses and is potentially fundamental to maximizing perceptual sensitivity. Despite its function being unclear, it has been hypothesized that sensory adaptation modifies the neurons' response codes, increasing the ability to process sensory signals on a larger scale. To better understand how such flexibility of our brain is possible, we investigated the effect of high- and low-frequency vibrotactile adaptation on perceived tactile temporal frequency during childhood, a time known for the brain to experience varying levels of plasticity. We tested tactile temporal frequency discrimination thresholds in both children and adults before and after tactile adaptation. Our results demonstrate that sensory adaptation does not consistently change perceived tactile temporal frequency in younger children as it does in adults, as adult-like trends begin to emerge at around 8 years of age but consolidate only in 10-year-old children. The absence of adaptation aftereffects suggests that, under certain conditions, sensory history does not affect perception in younger children in a similar way to adults. Surprisingly, younger children proved to be less flexible in modulating neural responses after prolonged exposure to an adapting stimulus, a tendency conflicting with the high plasticity levels the brain experiences during the early stages of life. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
感觉适应是神经反应的一种特定于特征的调节,可能是最大化感知灵敏度的基础。尽管其功能尚不清楚,但据推测,感觉适应会改变神经元的反应编码,提高在更大范围内处理感觉信号的能力。为了更好地理解我们大脑的这种灵活性是如何实现的,我们研究了高频和低频振动触觉适应对儿童期感知触觉时间频率的影响,儿童期是大脑经历不同程度可塑性的时期。我们在触觉适应前后测试了儿童和成人的触觉时间频率辨别阈值。我们的结果表明,感觉适应在年幼儿童中并不像在成人中那样一致地改变感知到的触觉时间频率,因为类似成人的趋势在8岁左右开始出现,但直到10岁儿童才巩固。适应后效的缺失表明,在某些条件下,感觉历史对年幼儿童感知的影响与成人不同。令人惊讶的是,年幼儿童在长时间暴露于适应刺激后,在调节神经反应方面表现出较低的灵活性,这种趋势与大脑在生命早期所经历的高可塑性水平相矛盾。(PsycInfo数据库记录(c)2022美国心理学会,保留所有权利)