When Remembering Causes Forgetting: Retrieval-Induced Forgetting as Recovery Failure

Neurophysiological Evidence for Semantic Processing of Irrelevant Speech and Own-Name Detection in a Virtual Café

The well-known "cocktail party effect" refers to incidental detection of salient words, such as one's own-name, in supposedly unattended speech. However, empirical investigation of the prevalence of this phenomenon and the underlying mechanisms has been limited to extremely artificial contexts and has yielded conflicting results. We introduce a novel empirical approach for revisiting this effect under highly ecological conditions, by immersing participants in a multisensory Virtual Café and using realistic stimuli and tasks. Participants (32 female, 18 male) listened to conversational speech from a character at their table, while a barista in the back of the café called out food orders. Unbeknownst to them, the barista sometimes called orders containing either their own-name or words that created semantic violations. We assessed the neurophysiological response-profile to these two probes in the task-irrelevant barista stream by measuring participants' brain activity (EEG), galvanic skin response and overt gaze-shifts.SIGNIFICANCE STATEMENT We found distinct neural and physiological responses to participants' own-name and semantic violations, indicating their incidental semantic processing despite being task-irrelevant. Interestingly, these responses were covert in nature and gaze-patterns were not associated with word-detection responses. This study emphasizes the nonexclusive nature of attention in multimodal ecological environments and demonstrates the brain's capacity to extract linguistic information from additional sources outside the primary focus of attention.

Bridging the Gap Between Second Language Acquisition Research and Memory Science: The Case of Foreign Language Attrition

The field of second language acquisition (SLA) is by nature of its subject a highly interdisciplinary area of research. Learning a (foreign) language, for example, involves encoding new words, consolidating and committing them to long-term memory, and later retrieving them. All of these processes have direct parallels in the domain of human memory and have been thoroughly studied by researchers in that field. Yet, despite these clear links, the two fields have largely developed in parallel and in isolation from one another. The present article aims to promote more cross-talk between SLA and memory science. We focus on foreign language (FL) attrition as an example of a research topic in SLA where the parallels with memory science are especially apparent. We discuss evidence that suggests that competition between languages is one of the mechanisms of FL attrition, paralleling the interference process thought to underlie forgetting in other domains of human memory. Backed up by concrete suggestions, we advocate the use of paradigms from the memory literature to study these interference effects in the language domain. In doing so, we hope to facilitate future cross-talk between the two fields and to further our understanding of FL attrition as a memory phenomenon.

Overcoming duality: the fused bousfieldian function for modeling word production in verbal fluency tasks

Word production is generally assumed to occur as a function of a broadly interconnected language system. In terms of verbal fluency tasks, word production dynamics can be assessed by analyzing respective time courses via curve fitting. Here, a new generalized fitting function is presented by merging the two dichotomous classical Bousfieldian functions into one overarching power function with an adjustable shape parameter. When applied to empirical data from verbal fluency tasks, the error of approximation was significantly reduced while also fulfilling the Bayesian information criterion, suggesting a superior overall application value. Moreover, the approach identified a previously unknown logarithmic time course, providing further evidence of an underlying lexical network structure. In view of theories on lexical access, the corresponding modeling differentiates task-immanent lexical suppression from automatic lexical coactivation. In conclusion, our approach indicates that process dynamics result from an increasing cognitive effort to suppress automatic network functions.

Stress eliminates retrieval-induced forgetting--does the oral application of cortisol?

It is well established that stress and glucocorticoids can affect memory. Psychosocial stress has been reported to eliminate retrieval-induced forgetting (RIF), the phenomenon that repeated retrieval of a subset of previously learned material impairs later recall of related, but non-retrieved information. The stress-related reduction of RIF has been found correlated with an increase in salivary cortisol levels. Based on these findings, the current placebo-controlled study examined the effect of an oral dose of 25mg hydrocortisone on the RIF effect in 37 healthy men. Even though participants in the hydrocortisone group showed a marked increase in salivary cortisol, retrieval-induced forgetting was not affected by the pharmacological treatment. Thus, cortisol administration alone in contrast to stress experience does not impair the RIF effect. However, participants with high state anxiety during retrieval practice did not show RIF, whereas participants with low state anxiety did. This finding suggests a role for state anxiety in stress-related elimination of retrieval-induced forgetting, perhaps indicative of a memory-modulating sympathetic nervous system effect.

Suppression in retrieval practice, part-set cueing, and negative priming memory: the hydrogen model

A number of phenomena in memory have been explained using appeals to active suppression processes, including retrieval practice, part-set cueing, and the negative priming that is observed with associative interference. However, more formal attempts to capture such processes have been absent. This paper outlines the hydrogen model of memory retrieval, which aims to be a simple model with the modest goal of trying to explore what influence suppression would have on memory retrieval. This model contains a single activation component and a single suppression component in which suppression comes into play only after retrieval interference has been detected. This model was created to explore the plausibility and viability of ideas about the operation of suppression during memory retrieval. For hydrogen, the degree of suppression recruited is proportional to the amount of interference experienced. Overall, the pattern of human data was captured by the suppression model.

The effect of practice on the recall of salient information in obsessive-compulsive disorder

Deficits in memory and cognitive inhibition have been proposed as underlying mechanisms of obsessive-compulsive disorder (OCD). To test this hypothesis, an emotional variant of the retrieval-induced forgetting (RIF) paradigm was constructed which investigates whether repeated retrieval of previously learned material (Rp+) leads to enhanced forgetting of related but nonretrieved material (Rp-) in comparison to unrelated material (NRp). Paradigm (involving OCD-relevant, neutral and negative material) was presented to 21 participants with OCD and 22 healthy controls. To compare personally relevant stimuli across groups, salience ratings of the material were included. RIF was not reduced in OCD per se. Tentative evidence was found for a weakened RIF effect for personally salient OCD-relevant material in OCD patients in comparison to healthy controls.

Examination of the Effects of Self-Modeling on Autobiographical Memory

The intent of this preliminary study is to explore the effectiveness of self-modeling in altering maladaptive behavior in children through the mediating effect of modifying their autobiographical memories of their dysfunctional behaviors. We proposed that the alteration of inappropriate classroom behaviors afforded by the self-modeling intervention would be accompanied by commensurate alteration in the memory of those behaviors and changes in self-concept. The process of a self-modeling intervention capitalizes on a broad range of experimentally confirmed phenomenal and experimental factors and mechanisms involved in memory alteration, providing sufficient cognitive, perceptual, contextual, semantic, and affective information to closely approximate a “true” memory, and facilitate source misattribution, suggestibility, biases, and thereby, memory alteration/implantation. Results of this study provided evidence of autobiographical memory alteration in narrative recall, recollective experience, and self-concept reports following self-modeling intervention. These initial findings support memory alteration as a mediating factor in eliciting behavior change through self-modeling intervention. However, this study should be replicated and expanded to definitively build the research on the relationship between malleability of memory relative to positive behavior changes.

Neural markers of inhibition in human memory retrieval

Retrieving particular information from memory facilitates the later retrieval of that information, but also impairs the later retrieval of related, interfering information. It has been theorized that this retrieval-induced forgetting reflects inhibition of interfering memory representations. We used event-related fMRI to investigate the functional neuroanatomy of this impaired retrieval, at the time the impairment is observed. Neural activity differences between impaired and facilitated information occurred in left ventrolateral prefrontal cortex (VLPFC, BA 45 and 47), precuneus (BA 7), and right inferior parietal lobule (IPL, BA 40). Activity in left anterior VLPFC (BA 47) and left posterior temporal cortex (BA 22), regions implicated in the controlled retrieval of weak semantic memory representations, predicted the degree of retrieval-induced forgetting. In contrast, activity in precuneus and right IPL predicted the degree of retrieval-induced facilitation. Our findings demonstrate that impairment of interfering memories and facilitation of practiced memories involve distinct neural processes, and suggest that the impairment reflects inhibition that weakens interfering memory representations.

Making Memories Unavailable

Abstract. Research from the past decades has shown that cuing and retrieval are not always beneficial for episodic memory and can also be detrimental. Prior work assumed that these detrimental effects are caused by retrieval blocking, in which cuing and retrieval strengthen material and the repeated involuntary sampling of the strengthened material hinders subsequent recall of nonstrengthened targets. Using a new experimental paradigm and an extended range of memory tests, recent research indicates that the detrimental effects of retrieval and cuing occur across a wide range of memory tests and are likely to be the result of inhibitory processes. These inhibitory processes impair the nonretrieved and noncue items' memory representation and make these items unavailable in memory. The recent results and the new theory are reviewed and discussed.

Inhibitory deficits in older adults: list-method directed forgetting revisited

In list-method directed forgetting, participants are cued to intentionally forget a previously studied list while remembering a subsequently presented 2nd list. Results from prior research are inconclusive on whether older adults show deficits in this type of task. In 3 experiments, the authors reexamined the issue and compared younger and older adults' responsiveness to the forget cue. Across the experiments, the forget cue was varied within and between participants, the 2 lists were unrelated and related to each other, and recall of the lists was required simultaneously and successively. In none of the 3 experiments did any age-related difference in directed forgetting performance emerge. List-method directed forgetting is assumed to reflect retrieval inhibition. The present results thus challenge the proposal of a general inhibitory deficit in older adults' memory performance.

When Remembering Causes Forgetting: Electrophysiological Correlates of Retrieval-Induced Forgetting

People tend to forget information that is related to memories they are actively trying to retrieve. On the basis of results from behavioral studies, such retrieval-induced forgetting is held to result from inhibitory control processes that are recruited to attenuate interference caused by competing memory traces. Employing electrophysiological measures of brain activity, the present study examined the neural correlates of these inhibitory processes as they operate. The results demonstrate that sustained prefrontal event-related potentials were 1) related to whether or not selective memory retrieval was required during reprocessing of previously studied words and 2) predictive of individual differences in the amount of forgetting observed in an ensuing recall test. The present findings give support to an inhibitory control account of retrieval-induced forgetting and are in accord with the view that prefrontal regions play an important role in the selection and maintenance of relevant memory representations at the expense of those currently irrelevant.

Part-list cuing can be transient and lasting: The role of encoding

The presentation of a subset of learned items as retrieval cues can have detrimental effects on recall of the remaining items. For 2 types of encoding conditions, the authors examined in 3 experiments whether such part-list cuing is a transient or a lasting phenomenon. Across the experiments, the detrimental effect of part-list cues was consistently found to be transient with a high degree of interim associations and lasting with a low degree. These results indicate that the persistence of part-list cuing depends on encoding, thus challenging both strategy disruption and retrieval inhibition as general accounts of part-list cuing. A 2-mechanism account is provided according to which the 2 mechanisms mediate the effect in different encoding conditions.