Beuzeron-Mangina J H
Neurosurgery Department, Montreal Neurological Institute, McGill University Montreal, Quebec, Canada.
Int J Psychophysiol. 1996 Apr-May;22(1-2):9-23. doi: 10.1016/0167-8760(96)00023-2.
The goals of this research were to use an original Memory Workload Paradigm with visually presented words and to explore the following points: (1) With depth electrodes, stereotaxically implanted in intracerebral structures bilaterally (amygdala, anterior hippocampus, posterior hippocampus, orbital-frontal, anterior cingulate gyrus and cortical areas) to delineate brain structures involved in this memory workload task. (2) To investigate whether a memory load effect can be demonstrated on the latencies and amplitudes of the late components of intracerebral event-related potentials (ERPs). (3) If a load effect is present, do intracerebral ERP latencies and amplitudes vary as a function of memory set size? The analysis of intracerebral ERPs revealed that a negative waveform with a maximum amplitude around 400 ms was the component which was significantly involved in memory workload tasks. Significant load effects for the N4 latency were found in both amygdalae and the left posterior hippocampus, as well as both anterior regions of the second temporal gyri (p < 0.01). The intracerebral N4 latency varied linearly as a function of set size while the amplitude varied quadratically for the right amygdala and the left posterior hippocampus (p < 0.05). The results support the conclusion that the Memory Workload Paradigm provides the possibility to use memory load effect on ERPs as a marker to identify which intracerebral structures are predominantly involved in memory functions.
本研究的目的是使用一种原始的记忆负荷范式，其中单词以视觉方式呈现，并探索以下几点：(1) 通过将深度电极立体定向双侧植入脑内结构（杏仁核、前海马体、后海马体、眶额叶、前扣带回和皮质区域），来描绘参与该记忆负荷任务的脑结构。(2) 研究记忆负荷效应是否能在脑内事件相关电位（ERP）晚期成分的潜伏期和波幅上得到体现。(3) 如果存在负荷效应，脑内ERP的潜伏期和波幅是否会随记忆集大小而变化？脑内ERP分析显示，一个最大波幅出现在约400毫秒左右的负向波是显著参与记忆负荷任务的成分。在双侧杏仁核、左侧后海马体以及双侧颞叶第二回的前部区域均发现了N4潜伏期的显著负荷效应（p < 0.01）。脑内N4潜伏期随集大小呈线性变化，而右侧杏仁核和左侧后海马体的波幅呈二次方变化（p < 0.05）。结果支持这样的结论，即记忆负荷范式提供了利用ERP上的记忆负荷效应作为标记来识别哪些脑内结构主要参与记忆功能的可能性。
