University of California, San Diego, USA.
J Cogn Neurosci. 2012 Jun;24(6):1398-410. doi: 10.1162/jocn_a_00220. Epub 2012 Mar 5.
Given the diversity of stimuli encountered in daily life, a variety of strategies must be used for learning new information. Relating and encoding visual and verbal stimuli into memory has been probed using various tasks and stimulus types. Engagement of specific subsequent memory and cortical processing regions depends on the stimulus modality of studied material; however, it remains unclear whether different encoding strategies similarly influence regional activity when stimulus type is held constant. In this study, participants encoded object pairs using a visual or verbal associative strategy during fMRI, and subsequent memory was assessed for pairs encoded under each strategy. Each strategy elicited distinct regional processing and subsequent memory effects: middle/superior frontal, lateral parietal, and lateral occipital for visually associated pairs and inferior frontal, medial frontal, and medial occipital for verbally associated pairs. This regional selectivity mimics the effects of stimulus modality, suggesting that cortical involvement in associative encoding is driven by strategy and not simply by stimulus type. The clinical relevance of these findings, probed in a patient with a recent aphasic stroke, suggest that training with strategies utilizing unaffected cortical regions might improve memory ability in patients with brain damage.
鉴于日常生活中遇到的刺激多样性，必须使用各种策略来学习新信息。已经使用各种任务和刺激类型来探测将视觉和言语刺激与记忆相关联和编码。特定的后续记忆和皮质处理区域的参与取决于所研究材料的刺激模态；但是，当刺激类型保持不变时，不同的编码策略是否同样影响区域活动仍不清楚。在这项研究中，参与者在 fMRI 期间使用视觉或言语联想策略对物体对进行编码，并评估了在每种策略下编码的对的后续记忆。每种策略都引起了不同的区域处理和后续记忆效应：与视觉相关的对是中/额上回、外侧顶叶和外侧枕叶，与言语相关的对是下额回、内侧额回和内侧枕叶。这种区域选择性模仿了刺激模态的影响，表明皮质在联想编码中的参与是由策略驱动的，而不仅仅是由刺激类型驱动的。在最近患有失语症中风的患者中进行的这些发现的临床相关性表明，使用未受影响的皮质区域的策略进行训练可能会提高脑损伤患者的记忆能力。
