The brain has the powerful ability to transform experiences into anatomic maps and continuously integrate massive amounts of information to form new memories. The manner in which the brain performs these processes has been investigated extensively for decades. Emerging reports suggest that dendritic spines are the structural basis of information storage. The complex orchestration of functional and structural dynamics of dendritic spines is associated with learning and memory. Owing to advancements in techniques, more precise observations and manipulation enable the investigation of dendritic spines and provide clues to the challenging question of how memories reside in dendritic spines. In this review, we summarize the remarkable progress made in revealing the role of dendritic spines in fear memory and the techniques used in this field.
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