生物谷報道：人的大腦能夠覺察環(huán)境中影像和聲音的細微變化,，不管是一閃而過的蚊子還是吉他手一個微小的失誤，我們都能夠立即輕而易舉地覺察到,。然而,，已有研究發(fā)現(xiàn)，大腦中變化前的映像和變化后的映像,，即使間隔了一小段時間,，也會干擾大腦檢測視覺差異的能力。
法國波爾多大學（University of Bordeaux）的科學家Laurent Demany等人說,，大腦必定以某種方式記住變化前的情景,。許多實驗已經證明，哪怕是100毫秒的短暫時間間隔,，也會嚴重干擾我們覺察周圍環(huán)境復雜圖像變化的能力,。這種現(xiàn)象被稱為“動態(tài)性失明”（change blindness）。
上述這些科學家最近研究了時間間隔對大腦覺察聲音變化的影響,。他們的目的是通過研究確定,，大腦是否用相同的機制來覺察影像和聲音的變化。參與試驗的人要在許多音調中,，覺察到一個音調的音高發(fā)生的變化,。試驗時，研究了不同的變化前聲音復雜程度和安靜的時間間隔,。
研究人員本來以為,，若是與覺察圖像變化的過程相似，大腦將在復雜的聲音環(huán)境中,，能記住的變化比在簡單的環(huán)境中要少,。但是他們的研究結果發(fā)現(xiàn),，盡管有時間上的延遲，參與實驗者還是能夠記住非常復雜的,、多達12種音調的變化,。
這項研究的結果表明，與影像相比,，人類大腦使用更復雜的機制來記住聲音，因此某種程度上說,，人對聲音的變化比對影像的變化更敏感,。
該研究結果發(fā)表在2008月1月的Psychological Science上。
生物谷推薦原始出處：
Psychological Science
Volume 19 Issue 1 Page 85-91, January 2008
To cite this article: Laurent Demany, Wiebke Trost, Maja Serman, Catherine Semal (2008)
Auditory Change Detection: Simple Sounds Are Not Memorized Better Than Complex Sounds
Psychological Science 19 (1), 85–91.
doi:10.1111/j.1467-9280.2008.02050.x
Auditory Change Detection: Simple Sounds Are Not Memorized Better Than Complex Sounds
Laurent Demany11Université Bordeaux 2 and Centre National de la Recherche Scientifique, Bordeaux, France, Wiebke Trost11Université Bordeaux 2 and Centre National de la Recherche Scientifique, Bordeaux, France, Maja Serman11Université Bordeaux 2 and Centre National de la Recherche Scientifique, Bordeaux, France, and Catherine Semal11Université Bordeaux 2 and Centre National de la Recherche Scientifique, Bordeaux, France
1Université Bordeaux 2 and Centre National de la Recherche Scientifique, Bordeaux, France
ABSTRACT—Previous research has shown that the detectability of a local change in a visual image is essentially independent of the complexity of the image when the interstimulus interval (ISI) is very short, but is limited by a low-capacity memory system when the ISI exceeds 100 ms. In the study reported here, listeners made same/different judgments on pairs of successive "chords" (sums of pure tones with random frequencies). The change to be detected was always a frequency shift in one of the tones, and which tone would change was unpredictable. Performance worsened as the number of tones increased, but this effect was not larger for 2-s ISIs than for 0-ms ISIs. Similar results were obtained when a chord was followed by a single tone that had to be judged as higher or lower than the closest component of the chord. Overall, our data suggest that change detection is based on different mechanisms in audition and vision.
