Conscious recollection and binding among context features

How rich are false memories in a naturalistic context in healthy aging?

The recall of factual and contextual information is a core characteristic of episodic memory sensitive to aging effects. The innovative aim of the present study was to assess in a naturalistic context the quantity and quality of correct and false free recalls among younger and older adults considering feature binding (What-Where-When-Details) and recollection (Remembering vs. Knowing). Thanks to virtual reality, we designed a multimodal environment simulating a lively town in which we implemented a variant of a DRM task rich in sets of semantically related items (e.g., fruits on a market stall). We asked 30 young and 30 older participants to navigate in the virtual environment, paying attention to the items, and then recall as many items and as much contextual information as possible and indicate the presence of recollection. As expected, older adults produced fewer correct recall but more intrusions than younger adults, and their correct recall was more deficient in binding and recollection. In both age groups, false recall was associated with the correct context inferred from a related set of items. However, the intrusions produced by older adults were highly recollected compared to those of the younger adults, and they were associated with false item-related contextual information.

United we fall: All-or-none forgetting of complex episodic events

Do complex event representations fragment over time, or are they instead forgotten in an all-or-none manner? For example, if we met a friend in a café and they gave us a present, do we forget the constituent elements of this event (location, person, and object) independently, or would the whole event be forgotten? Research suggests that item-based memories are forgotten in a fragmented manner. However, we do not know how more complex episodic, event-based memories are forgotten. We assessed both retrieval accuracy and dependency—the statistical association between the retrieval successes of different elements from the same event—for complex events. Across 4 experiments, we show that retrieval dependency is found both immediately after learning and following a 12-hr and 1-week delay. Further, the amount of retrieval dependency after a delay is greater than that predicted by a model of independent forgetting. This dependency was only seen for coherent “closed-loops,” where all pairwise associations between locations, people, and objects were encoded. When “open-loops” were learned, where only 2 out of the 3 possible associations were encoded, no dependency was seen immediately after learning or after a delay. Finally, we also provide evidence for higher retention rates for closed-loops than for open-loops. Therefore, closed-loops do not fragment as a function of forgetting and are retained for longer than are open-loops. Our findings suggest that coherent episodic events are not only retrieved, but also forgotten, in an all-or-none manner.

Non-monotonic relationships between emotional arousal and memory for color and location

Recent research points to the decreased diagnostic value of subjective retrieval experience for memory accuracy for emotional stimuli. While for neutral stimuli rich recollective experiences are associated with better context memory than merely familiar memories this association appears questionable for emotional stimuli. The present research tested the implicit assumption that the effect of emotional arousal on memory is monotonic, that is, steadily increasing (or decreasing) with increasing arousal. In two experiments emotional arousal was manipulated in three steps using emotional pictures and subjective retrieval experience as well as context memory were assessed. The results show an inverted U-shape relationship between arousal and recognition memory but for context memory and retrieval experience the relationship was more complex. For frame colour, context memory decreased linearly while for spatial location it followed the inverted U-shape function. The complex, non-monotonic relationships between arousal and memory are discussed as possible explanations for earlier divergent findings.

Analyzing Stochastic Dependence of Cognitive Processes in Multidimensional Source Recognition

Stochastic dependence among cognitive processes can be modeled in different ways, and the family of multinomial processing tree models provides a flexible framework for analyzing stochastic dependence among discrete cognitive states. This article presents a multinomial model of multidimensional source recognition that specifies stochastic dependence by a parameter for the joint retrieval of multiple source attributes together with parameters for stochastically independent retrieval. The new model is equivalent to a previous multinomial model of multidimensional source memory for a subset of the parameter space. An empirical application illustrates the advantages of the new multinomial model of joint source recognition. The new model allows for a direct comparison of joint source retrieval across conditions, it avoids statistical problems due to inflated confidence intervals and does not imply a conceptual imbalance between source dimensions. Model selection criteria that take model complexity into account corroborate the new model of joint source recognition.