Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
J Neurosci. 2012 Jan 25;32(4):1481-7. doi: 10.1523/JNEUROSCI.4497-11.2012.
The superior memory for emotional events has been attributed to the beneficial effects of noradrenaline released into the amygdala attributable to arousal. Noradrenaline mediates the effects of different hormones and neurotransmitters, including adrenal stress hormones on consolidation (McGaugh, 2004; Roozendaal et al., 2009). The majority of human fMRI studies of the enhancement of emotional memories contrasted successful encoding of emotionally arousing and neutral stimuli (LaBar and Cabeza, 2006; Murty et al., 2010). Recently, it was highlighted that emotional stimuli elicit not only arousal but also intensify cognitive processes that contribute to the enhanced memory. In particular, the enhanced use of selective attention as well as the greater distinctiveness and semantic relatedness of emotional stimuli influence memory formation (Talmi et al., 2007a). The present study aimed to explore the effects of arousal on memory formation independent of these cognitive factors in an event-related manner. Arousal was induced by the application of a nociceptive stimulus briefly after the presentation of neutral scenes. The results show a purely arousal-driven memory enhancement for the neutral scenes that differs in critical aspects from the superior memory for emotional stimuli. In particular, the enhancement was only evident after consolidation and exclusively based on an increase in item familiarity but not recollection. Moreover, successful memory formation for stimuli followed by arousal was correlated with activity in the parahippocampal cortex but not the amygdala, as is the case for emotional stimuli.
情绪事件的优越记忆归因于去甲肾上腺素释放到杏仁核，归因于唤醒。去甲肾上腺素介导不同激素和神经递质的作用，包括应激激素对巩固的影响（McGaugh，2004；Roozendaal 等人，2009）。大多数人类 fMRI 研究增强情绪记忆时，对比了成功编码情绪唤醒和中性刺激（LaBar 和 Cabeza，2006；Murty 等人，2010）。最近，有人强调情绪刺激不仅会引起唤醒，还会加剧有助于增强记忆的认知过程。特别是，选择性注意力的增强使用，以及情绪刺激的更大独特性和语义相关性，会影响记忆形成（Talmi 等人，2007a）。本研究旨在以事件相关的方式，在不考虑这些认知因素的情况下，探讨唤醒对记忆形成的影响。在呈现中性场景后，短暂地应用疼痛刺激来诱发唤醒。结果表明，中性场景存在纯粹由唤醒驱动的记忆增强，与情绪刺激的优越记忆在关键方面有所不同。特别是，只有在巩固后才会出现增强，并且仅基于项目熟悉度的增加，而不是回忆。此外，唤醒后成功的刺激记忆形成与海马旁皮质活动相关，但与杏仁核无关，就像情绪刺激一样。
