Constructive Memory and Conscious Experience.

Episodic memory relies on constructive processes that support simulating novel future events by flexibly recombining elements of past experiences, and that can also give rise to memory errors. In recent studies, we have developed methods to characterize the cognitive and neural processes that support conscious experiences linked to this process of episodic recombination, both when people simulate novel future events and commit recombination-related memory errors. In this Perspective, we summarize recent studies that illustrate these phenomena, and discuss broader implications for characterizing the basis of conscious experiences associated with constructive memory from a cognitive neuroscience perspective.

The dead salmon strikes again: Reports of unconscious processing in the hippocampus may reflect Type-I error.

Steinkrauss and Slotnick (2024) reviewed neuroimaging studies linking the hippocampus with implicit memory. They conclude that there is no convincing evidence that the hippocampus is associated with implicit memory because prior studies are confounded by explicit memory (among other factors). Here, we ask a different yet equally important question: do reports of unconscious hippocampal activity reflect a Type-I error (i.

Prefrontal cortex-mediated inhibition supports face recognition.

Inhibitory processes are thought to be important for memory function. A recent behavioral study that employed a face recognition paradigm reported that participants made fewer "old" responses to highly similar faces than less similar faces, providing evidence that memory for faces may rely on related-item inhibition. However, these results could also be explained by a non-inhibitory recall-to-reject process.

Impaired cognitive performance in older adults is associated with deficits in item memory and memory for object features.

Amnestic mild cognitive impairment (aMCI) is associated with damage to the perirhinal/entorhinal cortex, and consequently, deficits in item/object memory. However, cognitive assessments commonly used to identify individuals with aMCI require a clinician to administer and interpret the test. We developed a novel self-administered global cognitive assessment, called the Cognitive Assessment via Keyboard (CAKe).

Transcranial magnetic stimulation to the angular gyrus modulates the temporal dynamics of the hippocampus and entorhinal cortex.

Transcranial magnetic stimulation (TMS) delivered to the angular gyrus (AG) affects hippocampal function and associated behaviors (Thakral PP, Madore KP, Kalinowski SE, Schacter DL. Modulation of hippocampal brain networks produces changes in episodic simulation and divergent thinking. 2020a.

Constructive episodic retrieval processes underlying memory distortion contribute to creative thinking and everyday problem solving.

Constructive episodic retrieval processes play an adaptive role in supporting divergent thinking (i.e., creatively combining diverse bits of information) and means-end problem solving (i.

Representing the Good and Bad: fMRI signatures during the encoding of multisensory positive, negative, and neutral events.

Few studies have examined how multisensory emotional experiences are processed and encoded into memory. Here, we aimed to determine whether, at encoding, activity within functionally-defined visual- and auditory-processing brain regions discriminated the emotional category (i.e.

Sensitivity of the hippocampus to objective but not subjective episodic memory judgments.

We assessed whether neural activity in the hippocampus dissociates according to whether memory test items elicit a subjective sense of recollection or accurate retrieval of contextual information. We reanalyzed a previously acquired dataset from a study in which participants made both objective (source memory for spatial context) and subjective (Remember-Know) judgments for each test item. Results indicated that the hippocampus was exclusively sensitive to the amount of contextual information retrieved, such that accurate source memory judgments were associated with greater activity than inaccurate judgments, regardless of Remember/Know status.

Linking creativity and false memory: Common consequences of a flexible memory system.

Episodic retrieval plays a functional-adaptive role in supporting divergent thinking, the ability to creatively combine different pieces of information. However, the same constructive memory process that provides a functional-adaptive benefit can also leave memory prone to error. In two experiments, we employed an individual differences approach to examine the relationship between different forms of creative thinking (divergent and convergent thinking) and false memory generation in the Deese-Roediger-McDermott paradigm.

Divergent thinking and constructing future events: dissociating old from new ideas.

Divergent thinking (the ability to generate creative ideas by combining diverse types of information) has been previously linked to the ability to imagine novel and specific future autobiographical events. Here, we examined whether divergent thinking is differentially associated with the ability to construct novel imagined future events and recast future events (i.e.

Distinct patterns of hippocampal activity associated with color and spatial source memory.

The hippocampus is known to be involved in source memory across a wide variety of stimuli and source types. Thus, source memory activity in the hippocampus is thought to be domain-general such that different types of source information are similarly processed in the hippocampus. However, there is some evidence of domain-specificity for spatial and temporal source information.

Decoding the emotional valence of future thoughts.

Affective future thinking allows us to prepare for future outcomes, but we know little about neural representation of emotional future simulations. We used a multi-voxel pattern analysis to determine whether patterns of neural activity can reliably distinguish between positive and negative future simulations. Neural patterning in the anterior cingulate and ventromedial prefrontal cortices distinguished positive from negative future simulations, indicating that these regions code for the emotional valence of future events.

Reinstatement of item-specific contextual details during retrieval supports recombination-related false memories.

Flexible retrieval mechanisms that allow us to infer relationships across events may also lead to memory errors or distortion when details of one event are misattributed to the related event. Here, we tested how making successful inferences alters representation of overlapping events, leading to false memories. Participants encoded overlapping associations ('AB' and 'BC'), each of which was superimposed on different indoor and outdoor scenes that were pre-exposed prior to associative learning.

High confidence spatial long-term memories produce greater cortical activity in males than females.

Many functional resonance imaging (fMRI) studies have reported sex differences during long-term memory. The present fMRI investigation aimed to identify whether sex differences exist during high- versus low-confidence accurate spatial memories. During the study phase, abstract shapes were presented to the left or right of fixation.

Age-related changes in repetition suppression of neural activity during emotional future simulation.

Despite advances in understanding the consequences of age-related episodic memory decline for future simulation, much remains unknown regarding changes in the neural underpinnings of future thinking with age. We used a repetition suppression paradigm to explore age-related changes in the neural correlates of emotional future simulation. Younger and older adults simulated positive, negative, and neutral future events either 2 or 5 times.

Modulation of hippocampal brain networks produces changes in episodic simulation and divergent thinking.

Prior functional magnetic resonance imaging (fMRI) studies indicate that a core network of brain regions, including the hippocampus, is jointly recruited during episodic memory, episodic simulation, and divergent creative thinking. Because fMRI data are correlational, it is unknown whether activity increases in the hippocampus, and the core network more broadly, play a causal role in episodic simulation and divergent thinking. Here we employed fMRI-guided transcranial magnetic stimulation (TMS) to assess whether temporary disruption of hippocampal brain networks impairs both episodic simulation and divergent thinking.

The anterior hippocampus is associated with spatial memory encoding.

There are many hypotheses regarding specialization of the anterior versus posterior hippocampus including memory encoding versus retrieval and other cognitive processes versus spatial memory. In the present functional magnetic resonance imaging study, we distinguished between the hypothesis linking encoding to the anterior hippocampus and the hypothesis linking spatial memory to the posterior hippocampus by evaluating whether spatial memory encoding involved the anterior hippocampus or the posterior hippocampus. During encoding, participants viewed abstract shapes in each of four visual field quadrants while instructed to maintain central fixation.

The core episodic simulation network dissociates as a function of subjective experience and objective content.

Episodic simulation - the mental construction of a possible future event - has been consistently associated with enhanced activity in a set of neural regions referred to as the core network. In the current functional neuroimaging study, we assessed whether members of the core network are differentially associated with the subjective experience of future events (i.e.

Reinstatement of Event Details during Episodic Simulation in the Hippocampus.

According to the constructive episodic simulation hypothesis, episodic simulation (i.e., imagining specific novel future episodes) draws on some of the same neurocognitive processes that support episodic memory (i.

Adaptive constructive processes: An episodic specificity induction impacts false recall in the Deese-Roediger-McDermott paradigm.

Numerous studies indicate that an episodic specificity induction (ESI)-brief training in recollecting the details of a past experience-enhances performance on subsequent tasks that rely on episodic retrieval, including autobiographical memory, imagination, problem solving, and creative thinking. In 5 experiments, we examined whether these benefits of the ESI extend to reducing susceptibility to false memory, or whether they are accompanied by a cost in the form of increased susceptibility to false memory. To assess how ESI impacts false memory generation, we used the Deese-Roediger-McDermott (DRM) paradigm, a reliable procedure for generating false memories.

Effects of age on across-participant variability of cortical reinstatement effects.

Using functional magnetic resonance imaging data, we assessed whether across-participant variability of content-selective retrieval-related neural activity differs with age. We addressed this question by employing across-participant multi-voxel pattern analysis (MVPA), predicting that increasing age would be associated with reduced variability of retrieval-related cortical reinstatement across participants. During study, 24 young and 24 older participants viewed objects and concrete words.

Core Network Contributions to Remembering the Past, Imagining the Future, and Thinking Creatively.

The core network refers to a set of neural regions that have been consistently associated with episodic memory retrieval and episodic future simulation. This network is thought to support the constructive thought processes that allow the retrieval and flexible combination of stored information to reconstruct past and construct novel future experiences. Recent behavioral research points to an overlap between these constructive processes and those also engaged during divergent thinking-the ability to think creatively and generate novel ideas-but the extent to which they involve common neural correlates remains unclear.

Content-specific phenomenological similarity between episodic memory and simulation.

Numerous studies have indicated that remembering specific past experiences (i.e., episodic memory) and imagining specific novel future experiences (i.

Transcranial magnetic stimulation of the left angular gyrus during encoding does not impair associative memory performance.

The left angular gyrus (AG) is thought to play a critical role in episodic retrieval and has been implicated in the recollection of specific details of prior episodes. Motivated by recent fMRI studies in which it was reported that elevated neural activity in left AG during study is predictive of subsequent associative memory, the present study investigated whether the region plays a causal role in associative memory encoding. Participants underwent online transcranial magnetic stimulation (TMS) while encoding word pairs prior to an associative memory test.

Neural Mechanisms of Episodic Retrieval Support Divergent Creative Thinking.

Prior research has indicated that brain regions and networks that support semantic memory, top-down and bottom-up attention, and cognitive control are all involved in divergent creative thinking. Kernels of evidence suggest that neural processes supporting episodic memory-the retrieval of particular elements of prior experiences-may also be involved in divergent thinking, but such processes have typically been characterized as not very relevant for, or even a hindrance to, creative output. In the present study, we combine functional magnetic resonance imaging with an experimental manipulation to test formally, for the first time, episodic memory's involvement in divergent thinking.