大腦皮層的區(qū)域差別
Cable connections. An
axial section through the human brain showing Brodmann's area 22 and the primary auditory cortex in both the left and right
hemisphere. In area 22 of the left hemisphere (which is preferentially activated during language processing) clusters of Neurons are spaced further apart and are cabled together with
longer axons than the neuronal clusters in area 22 of the right
, 百拇醫(yī)藥
hemisphere. This asymmetry is not apparent in the primary
auditory cortex where the neuronal clusters in both hemispheres
have the same spacing. (The neuronal clusters in area 22 and in
the primary auditory cortex are the same size in both
hemispheres.)
關(guān)于大腦皮層各區(qū)域微結(jié)構(gòu)的了解還處于萌芽期。為什么這個區(qū)域是處理語言，為什么另一些是處理認知，各區(qū)域的神經(jīng)元分布組織有什么不同之處嗎?
, 百拇醫(yī)藥
為了回答這個問題，傳統(tǒng)解剖學家做出了大腦皮層初步的草圖，指出，大腦皮層不同區(qū)域的神經(jīng)元簇在大小和厚度上是有差別的。而有了現(xiàn)代的神經(jīng)科學手段，我們對大腦受到輸入信號刺激時各皮層區(qū)域神經(jīng)遞質(zhì)釋放的大致模式也了解了一些。而關(guān)于大腦左右兩半球相應(yīng)位置的細胞學、結(jié)構(gòu)學方面的研究卻很少，這些對應(yīng)區(qū)域在解剖學上非常相似，但在功能上卻相去甚遠。
ScienceV289 No.5486 期上 Enter Galuske et al.的報道彌補了這一缺憾。他們通過carbocyanine對死者大腦組織染色，檢測了兩半球Brodmann's22區(qū)域的差別。
在左半球，22區(qū)與語言有關(guān)，對分辨和產(chǎn)生詞匯非常重要，而右半球的22區(qū)則幫助分辨聲音的音律、音調(diào)和音強。
作者發(fā)現(xiàn)左右半球的22區(qū)都散布著神經(jīng)元簇，幾乎所有的神經(jīng)簇的大小都一致。但在左半球的22區(qū)，比右半球相應(yīng)區(qū)域神經(jīng)元分布的更分散，且有更長的軸突。在左半球22區(qū)及其他處理語言的區(qū)域中，錐體細胞比右半球22區(qū)中最大的錐體細胞還要大。作者認為細胞更大將會有更長的軸突，從而能將左半球幾個處理語言的區(qū)域聯(lián)系起來。
, 百拇醫(yī)藥
Enter
Galuske et al.的出色工作證明神經(jīng)心理學、大腦解剖學和神經(jīng)元的細胞分子生物學正在融合在一起。
相關(guān)文章：
F. E. Bloom, A. Björklund, T. Hökfelt, Eds., Handbook of Chemical Neuroanatomy, The Primate Nervous System, part 1, vol. 13 (1997) [publisher's information]; part 2, vol. 14 (1998) [publisher's information]; and part 3, vol. 15 (1999) (Elsevier, Amsterdam)
[publisher's information]. R. A. W. Galuske, W. Schlote, H. Bratzke, W. Singer, Science 289, 1946 (2000). J. M. Allman, Evolving Brains (Scientific American Library Series No. 68,New York, 1999) [publisher's information]. J. J. Hutsler and M. S. Gazzaniga, Cereb. Cortex 6, 260 (1996) [Medline];
, 百拇醫(yī)藥
T. L. Hayes and D. A. Lewis, Brain Lang. 49, 289 (1995) [Medline]. K.
Brodmann, in Some Papers on the Cerebral Cortex, G. von bonin, Transl. (Thomas, Springfield, IL, 1960). J. C. Piacentini and G. W. Hynd, Clin. Psychol. Rev. 8, 595 (1988). W.
Singer, in Pattern Recognition by Self-Organizing Neural Networks, G. A. Carpenter and S. Grossberg, Eds. (MIT Press, Cambridge, MA, 1991)
[publisher's information]. V. M. Brown et al., personal communication. R.
Gallistel, in the New Cognitive Neurosciences (MIT Press, Cambridge, MA, 2000), 百拇醫(yī)藥
axial section through the human brain showing Brodmann's area 22 and the primary auditory cortex in both the left and right
hemisphere. In area 22 of the left hemisphere (which is preferentially activated during language processing) clusters of Neurons are spaced further apart and are cabled together with
longer axons than the neuronal clusters in area 22 of the right
, 百拇醫(yī)藥
hemisphere. This asymmetry is not apparent in the primary
auditory cortex where the neuronal clusters in both hemispheres
have the same spacing. (The neuronal clusters in area 22 and in
the primary auditory cortex are the same size in both
hemispheres.)
關(guān)于大腦皮層各區(qū)域微結(jié)構(gòu)的了解還處于萌芽期。為什么這個區(qū)域是處理語言，為什么另一些是處理認知，各區(qū)域的神經(jīng)元分布組織有什么不同之處嗎?
, 百拇醫(yī)藥
為了回答這個問題，傳統(tǒng)解剖學家做出了大腦皮層初步的草圖，指出，大腦皮層不同區(qū)域的神經(jīng)元簇在大小和厚度上是有差別的。而有了現(xiàn)代的神經(jīng)科學手段，我們對大腦受到輸入信號刺激時各皮層區(qū)域神經(jīng)遞質(zhì)釋放的大致模式也了解了一些。而關(guān)于大腦左右兩半球相應(yīng)位置的細胞學、結(jié)構(gòu)學方面的研究卻很少，這些對應(yīng)區(qū)域在解剖學上非常相似，但在功能上卻相去甚遠。
ScienceV289 No.5486 期上 Enter Galuske et al.的報道彌補了這一缺憾。他們通過carbocyanine對死者大腦組織染色，檢測了兩半球Brodmann's22區(qū)域的差別。
在左半球，22區(qū)與語言有關(guān)，對分辨和產(chǎn)生詞匯非常重要，而右半球的22區(qū)則幫助分辨聲音的音律、音調(diào)和音強。
作者發(fā)現(xiàn)左右半球的22區(qū)都散布著神經(jīng)元簇，幾乎所有的神經(jīng)簇的大小都一致。但在左半球的22區(qū)，比右半球相應(yīng)區(qū)域神經(jīng)元分布的更分散，且有更長的軸突。在左半球22區(qū)及其他處理語言的區(qū)域中，錐體細胞比右半球22區(qū)中最大的錐體細胞還要大。作者認為細胞更大將會有更長的軸突，從而能將左半球幾個處理語言的區(qū)域聯(lián)系起來。
, 百拇醫(yī)藥
Enter
Galuske et al.的出色工作證明神經(jīng)心理學、大腦解剖學和神經(jīng)元的細胞分子生物學正在融合在一起。
相關(guān)文章：
F. E. Bloom, A. Björklund, T. Hökfelt, Eds., Handbook of Chemical Neuroanatomy, The Primate Nervous System, part 1, vol. 13 (1997) [publisher's information]; part 2, vol. 14 (1998) [publisher's information]; and part 3, vol. 15 (1999) (Elsevier, Amsterdam)
[publisher's information]. R. A. W. Galuske, W. Schlote, H. Bratzke, W. Singer, Science 289, 1946 (2000). J. M. Allman, Evolving Brains (Scientific American Library Series No. 68,New York, 1999) [publisher's information]. J. J. Hutsler and M. S. Gazzaniga, Cereb. Cortex 6, 260 (1996) [Medline];
, 百拇醫(yī)藥
T. L. Hayes and D. A. Lewis, Brain Lang. 49, 289 (1995) [Medline]. K.
Brodmann, in Some Papers on the Cerebral Cortex, G. von bonin, Transl. (Thomas, Springfield, IL, 1960). J. C. Piacentini and G. W. Hynd, Clin. Psychol. Rev. 8, 595 (1988). W.
Singer, in Pattern Recognition by Self-Organizing Neural Networks, G. A. Carpenter and S. Grossberg, Eds. (MIT Press, Cambridge, MA, 1991)
[publisher's information]. V. M. Brown et al., personal communication. R.
Gallistel, in the New Cognitive Neurosciences (MIT Press, Cambridge, MA, 2000), 百拇醫(yī)藥
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