靈活而目標(biāo)明確的行為能力要求在短時(shí)間內(nèi)保持積極記憶和控制多種類型的信息,，這種能力稱為“工作記憶（WM）”。大腦接受的信息會(huì)自動(dòng)保存在工作記憶中,，如何描述和控制這些信息對(duì)了解大腦如何指導(dǎo)行為至關(guān)重要,。
通常情況下，人們通過(guò)具體信息的刺激物來(lái)進(jìn)行研究,，如地點(diǎn)或文字,。然而最近，研究人員一直在強(qiáng)調(diào)規(guī)則的重要性,，即在刺激因素與等待回應(yīng)之間建立聯(lián)系,。在7月10日《神經(jīng)元》（Neuron）雜志發(fā)表的一篇文章中，Montojo和 Courtney 等人將心算與功能磁共振成像進(jìn)行關(guān)聯(lián)研究,，測(cè)試在WM區(qū)控制下更新的數(shù)字（即刺激物）和更新的數(shù)學(xué)運(yùn)算（即規(guī)則）是否依賴于相同的神經(jīng)系統(tǒng),。
結(jié)果表明，雖然一個(gè)共同的神經(jīng)網(wǎng)絡(luò)激活這兩種類型的更新,，但更新規(guī)則卻優(yōu)先激活大腦皮層前額葉,，而更新數(shù)字則優(yōu)先激活大腦皮層頂葉。新研究結(jié)果說(shuō)明,，數(shù)字和運(yùn)算規(guī)則同時(shí)在WM中儲(chǔ)存,，但它們卻具有兩種不同的神經(jīng)激活機(jī)制。（生物谷Bioon.com）
生物谷推薦原始出處：
Neuron,，Vol 59, 173-182, 10 July 2008,，Caroline A. Montojo and Susan M. Courtney
Differential Neural Activation for Updating Rule versus Stimulus Information in Working Memory
Caroline A. Montojo1 and Susan M. Courtney1,2,3,
1 Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD 21218-2686, USA
2 Department of Neuroscience, Johns Hopkins University, Baltimore, MD 21218-2686, USA
3 F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD 21218-2686, USA
Corresponding author
Susan M. Courtney
[email protected]
Summary
Establishing what information is actively maintained in working memory (WM) and how it is represented and controlled is essential to understanding how such information guides future behavior. WM has traditionally been investigated in terms of the maintenance of stimulus-specific information, such as locations or words. More recently, investigators have emphasized the importance of rules that establish relationships between those stimuli and the pending response. The current study used a mental arithmetic task with fMRI to test whether updating of numbers (i.e., stimuli) and updating of mathematical operations (i.e., rules) in WM relies on the same neural system. Results indicate that, while a common network is activated by both types of updating, rule updating preferentially activates prefrontal cortex while number updating preferentially activates parietal cortex. The results suggest that both numbers and rules are maintained in WM but that they are different types of information that are controlled independently.
