A major characteristic of our ability to remember things over short periods (ie seconds) is to remember sequences of information; that is, remember the order of events or items. One popular explanation for this ability is that we remember the order of items by associating an item with a 'tag' representing its position in a sequence or its time of occurrence. This project is intended to further constrain variants of this view of short-term memory, and to examine the precise nature of the 'tags' used to code the order of items, and how these tags are accessed to recall items. One question is how these tags are generated, and whether theories in which the tags come from an internal 'clock' hold validity. The project will also consider how we access these tags: Can we access them directly, or do we need to 'scan through' a sequence of tags to get to the one we need? Finally, it is commonly assumed that grouping sub-sequences in a sequence results in a hierarchical representation, with items/events at one level and groups represented at a higher level. The project will determine to what extent these levels can be accessed independently, or whether the group level is the doorway to the item/event level.