Department of Experimental Psychology, University of Oxford, Oxford, UK.
Department of Psychology, University of Toronto Scarborough, Toronto, ON, Canada.
Eur J Neurosci. 2021 Dec;54(11):7918-7945. doi: 10.1111/ejn.15535. Epub 2021 Dec 2.
According to dual-process signal-detection (DPSD) theories, short- and long-term recognition memory draws upon both familiarity and recollection. It remains unclear how primate prefrontal cortex (PFC) contributes to these processes, but frequency-specific neuronal activities are considered to play a key role. In Experiment 1, nonhuman primate (NHP) local field potential (LFP) electrophysiological recordings in macaque left dorsolateral PFC (dlPFC) revealed performance-related differences in a low-beta frequency range during the sample presentation phase of a visual object recognition memory task. Experiment 2 employed a similar task in humans and targeted left dlPFC (and vertex as a control) with repetitive transcranial magnetic stimulation (rTMS) at 12.5 Hz during occasional sample presentations. This low-beta frequency rTMS to dlPFC decreased DPSD derived indices of recollection, but not familiarity, in subsequent memory tests of the targeted samples after short delays. The same number of rTMS pulses over the same total duration albeit at a random frequency had no effect on either recollection or familiarity. Neither stimulation protocols had any causal effect upon behaviour when targeted to the control site (vertex). In this study, our hypotheses for our human TMS study were derived from our observations in NHPs; this approach might inspire further translational research through investigation of homologous brain regions and tasks across species using similar neuroscientific methodologies to advance the neural mechanism of recognition memory in primates.
根据双加工信号检测(DPSD)理论,短期和长期识别记忆既依赖于熟悉度,也依赖于记忆恢复。目前尚不清楚灵长类动物前额叶皮层(PFC)如何促进这些过程,但频率特异性神经元活动被认为起着关键作用。在实验 1 中,在猕猴左侧背外侧前额叶皮层(dlPFC)进行的非人类灵长类动物(NHP)局部场电位(LFP)电生理记录显示,在视觉物体识别记忆任务的样本呈现阶段,低频范围内存在与表现相关的差异。实验 2 在人类中采用了类似的任务,并在目标左侧 dlPFC(以及顶点作为对照)进行了重复经颅磁刺激(rTMS),在偶尔的样本呈现时以 12.5 Hz 的频率进行刺激。这种低频 beta 频率 rTMS 到 dlPFC 降低了随后的记忆测试中基于 DPSD 的记忆恢复指标,但对短期延迟后的目标样本的熟悉度没有影响。在相同的总持续时间内,即使以随机频率施加相同数量的 rTMS 脉冲,对记忆恢复或熟悉度也没有影响。当刺激目标为对照部位(顶点)时,这两种刺激方案对行为均无因果影响。在这项研究中,我们对人类 TMS 研究的假设是从我们对非人类灵长类动物的观察中得出的;这种方法可能会通过在不同物种中使用类似的神经科学方法研究同源大脑区域和任务来激励进一步的转化研究,从而推进灵长类动物识别记忆的神经机制。