Implicit Memory Research Articles

An ERP measure of non-conscious memory reveals dissociable implicit processes in human recognition using an open-source automated analytic pipeline.

Non-conscious processing of human memory has traditionally been difficult to objectively measure and thus understand. A prior study on a group of hippocampal amnesia (N = 3) patients and healthy controls (N = 6) used a novel procedure for capturing neural correlates of implicit memory using event-related potentials (ERPs): old and new items were equated for varying levels of memory awareness, with ERP differences observed from 400 to 800 ms in bilateral parietal regions that were hippocampal-dependent. The current investigation sought to address the limitations of that study by increasing the sample of healthy subjects (N = 54), applying new controls for construct validity, and developing an improved, open-source tool for automated analysis of the procedure used for equating levels of memory awareness. Results faithfully reproduced prior ERP findings of parietal effects that a series of systematic control analyses validated were not contributed to nor contaminated by explicit memory. Implicit memory effects extended from 600 to 1000 ms, localized to right parietal sites. These ERP effects were found to be behaviorally relevant and specific in predicting implicit memory response times, and were topographically dissociable from other traditional ERP measures of implicit memory (miss vs. correct rejections) that instead occurred in left parietal regions. Results suggest first that equating for reported awareness of memory strength is a valid, powerful new method for revealing neural correlates of non-conscious human memory, and second, behavioral correlations suggest that these implicit effects reflect a pure form of priming, whereas misses represent fluency leading to the subjective experience of familiarity.

Effets de la thérapie d’Intégration du Cycle de Vie sur l’anxiété et la régulation émotionnelle : premiers éléments d’évaluation à partir d’une étude de cas pragmatique

ObjectivesLifespan Integration therapy is an innovative approach developed in 2002 by Peggy Pace, initially for people who have experienced trauma or who have anxiety disorders and difficulties in managing emotions. It first appeared in France around 2012, notably with the work of Joanna Smith, but research on its effectiveness is still lacking. The question of the effects of a Lifespan Integration therapist's actions remains to be explored. Lifespan Integration therapy is based on numerous neurobiological postulates (polyvagal theory or TPV, autobiographical memory and self-defining memories, implicit memory, traumatic memory and Multiple Trace Theory or MTT, etc.). It is also based on the attachment theory while integrating theoretical concepts from the systemic theory (trigenerational, loyalties, resonances, etc.). It is therefore a therapy that could be described as integrative, based on the bottom-up circuit rather than on the top-down one, like most so-called “talk” therapies. Within the framework of the Change Process Research paradigm and according to the methodology of the pragmatic case study, we wanted to identify, describe, and explain the processes of change that this innovative approach allows. Our study is based on 6 completed therapies. PatientIn this article, we will present a pragmatic case study of a 32-year-old female patient, who had a generalized anxiety disorder at the beginning of therapy. Her Lifespan Integration therapy lasted 18 months, with 34 sessions and resulted not only in a decrease in anxiety but also in an improvement in the quality of her emotional management. MethodsMeasures were completed every six months: (1) the Difficulties Emotion Regulation Scale (DERS-f) for emotion regulation difficulties, (2) the Penn State Worry Questionnaire (PSWQ) for generalized anxiety disorder, and (3) the State Trait Anxiety Inventory (STAI) for traits of anxiety. We applied the pragmatic case study (Fishman, 1999) to determine the processes of change and to identify the pivotal moments of psychotherapy. A follow-up interview was used to explore the patients’ perspectives on their own improvement and to trace significant events in the recorded therapy sessions. It was carried out by another psychologist in order to reduce any biases related to the dual role of “therapist-researcher”. ResultsThe results of the questionnaires show a significant improvement in the symptoms of GAD, a very clear improvement in the subject's emotional management, which is accompanied by a decrease of the symptomatology. All the dimensions assessed with the DERS-f were initially affected except impulsivity. After six months of psychotherapy, all the dimensions gradually reached the norm. Moreover, significant events during the therapeutic process were noted by the client during the follow-up interview, highlighting the pivotal moment of the psychotherapy. Indeed, it was after having carried out the first phase of the therapy, based on the consolidation and reconsolidation of the memory, that we were able to approach, with the subject's consent, the event that might have been at the origin of the GAD: her uncle's death when she was six. We then carried out a standard protocol on this event. This is a protocol which consists of revisiting the scene of the memory in the company of the adult-self coming to support the child-self in the various phases structuring this protocol until there is a calming of the various parts of the self. We can thus note that it is precisely following this session that the emotional regulation, already clearly improved, was found to return to the norm. This very significant improvement in emotional regulation continued during the next phase of the therapy. ConclusionLifespan Integration Therapy has reported important clinical outcomes to date, but the studies have not yet been sufficiently developed. It would be interesting to extend this research to a larger population in order to validate the different effects observed in this clinic as demonstrated by Reijil & al in 2020. Additional studies, particularly investigating sleep and eating disorders, would be welcome. Indeed, we have observed a significant effect on these different domains, which seems to be evident from the moment that emotional regulation becomes effective, and precisely because emotions are involved in these functions.

Cognitive Development as a Piece of the Language Learning Puzzle

Why do children learn language more easily than adults do? This puzzle has fascinated cognitive and language scientists for decades. In the present letter, we approach the language learning puzzle from a cognitive perspective that is inspired by evidence from the perceptual and motor learning literature. Neuroscientific studies show that two memory systems in the brain are involved in human learning: an early implicit procedural memory system and a late-developing cognitive or declarative memory system. We argue that higher cognitive development constrains implicit statistical learning processes that are essential for learning patterns and regularities in languages, that is, the adult cognitive architecture has a cost. This is supported by experimental evidence showing that acquisition of implicit linguistic knowledge is enhanced under cognitive depletion in adults. More research is needed to test the cognitive cost hypothesis as it could partly solve the language learning puzzle.

Can placebo or nocebo pills improve or impair cognition performance?

Although the placebo effect is well known to affect many behaviors, the effects on cognitive performance are less well investigated. In this study, the effects of a placebo and a nocebo manipulation on cognitive performance was investigated in healthy young participants in an unblinded between-subjects study. In addition, the participants were asked about their subjective experience in the placebo and nocebo condition. The data suggested that the placebo condition induced the feeling of being more attentive and more motivated and the nocebo condition induced a feeling of being less attentive and alert and that they performed less well than normal. However, no placebo or nocebo effects were found on the actual performance on word learning, working memory, Tower of London task, or spatial pattern separation. These findings further support the notion that placebo or nocebo effects are not likely to occur in young healthy volunteers. However, other studies suggest that placebo effects can be found in implicit memory tasks and in participants with memory problems. Further placebo/nocebo studies are indicated using different experimental designs and different populations in order to better understand the placebo effect on cognitive performance.

A double dissociation between savings and long-term memory in motor learning.

Memories are easier to relearn than learn from scratch. This advantage, known as savings, has been widely assumed to result from the reemergence of stable long-term memories. In fact, the presence of savings has often been used as a marker for whether a memory has been consolidated. However, recent findings have demonstrated that motor learning rates can be systematically controlled, providing a mechanistic alternative to the reemergence of a stable long-term memory. Moreover, recent work has reported conflicting results about whether implicit contributions to savings in motor learning are present, absent, or inverted, suggesting a limited understanding of the underlying mechanisms. To elucidate these mechanisms, we investigate the relationship between savings and long-term memory by experimentally dissecting the underlying memories based on short-term (60-s) temporal persistence. Components of motor memory that are temporally-persistent at 60 s might go on to contribute to stable, consolidated long-term memory, whereas temporally-volatile components that have already decayed away by 60 s cannot. Surprisingly, we find that temporally-volatile implicit learning leads to savings, whereas temporally-persistent learning does not, but that temporally-persistent learning leads to long-term memory at 24 h, whereas temporally-volatile learning does not. This double dissociation between the mechanisms for savings and long-term memory formation challenges widespread assumptions about the connection between savings and memory consolidation. Moreover, we find that temporally-persistent implicit learning not only fails to contribute to savings, but also that it produces an opposite, anti-savings effect, and that the interplay between this temporally-persistent anti-savings and temporally-volatile savings provides an explanation for several seemingly conflicting recent reports about whether implicit contributions to savings are present, absent, or inverted. Finally, the learning curves we observed for the acquisition of temporally-volatile and temporally-persistent implicit memories demonstrate the coexistence of implicit memories with distinct time courses, challenging the assertion that models of context-based learning and estimation should supplant models of adaptive processes with different learning rates. Together, these findings provide new insight into the mechanisms for savings and long-term memory formation.

Пространственные представления и ментальные карты водителей

<p style="text-align: justify;">The article is devoted to the study of spatial representations and mental maps of drivers. The analysis of national and foreign psychological and socio-psychological sources of literature in the chosen topic was carried out. The scheme of functioning of the representations of drivers based on the interaction between explicit, implicit long-term memory and working memory at the levels of attention and automatisms is given. The cycles of learning and search, learning and activation, cycles of attention control are singled out. Driver behavior is seen as knowledge-based, rule-based and skill-based. The history of the emergence and development of mental maps, the mechanisms for the formation of drivers' ideas and the potential for using mental maps as an evaluation and control tool for the psychological diagnosis of driver candidates are described. For further research on this topic, the article presents the advantages of mental maps as a control and evaluation tool, and provides “lines of analysis” for interpreting test results. The creation of a methodology for mental maps of drivers is able to satisfy the need for effective diagnostic and research methods aimed at determining the competence of drivers and identifying links between driving style and features of mental maps, as well as predicting the inclination to create accidents on the roads.</p>

Effect of Scent Leaf (Ocimum gratissimum) Aqueous Extract on Neuromuscular Functions of Albino Rats (Rattus norvegicus)

Ocimum gratissimum (O.G.) (scent leaf) has been used for the treatment of various disease situations from ancient time because of its anti-convulsion, anti-diabetic anti septic, antibacterial, anticancer, antioxidant properties. In the present study, the effects of O.G extract preparation was evaluated on the neuromuscular system of the albino Wister rat (Rattus norvegicus). Twenty five young animals of 40-90g were used for the experiment. They were divided into five groups of five animals per group. The different groups (groups 2, 3, 4, and 5) were administered with 100mg/kg, 200mg/kg, 400mg/kg, and 800mg/kg daily, respectively while group 1 was used as the control. The neuromuscular activities were assessed and studied by using scientific assays like the handgrip test, inverted screen test, swimming test, and the beam walking for checking non-declarative memory function. From the result obtained , One way analysis of variance (ANOVA) was used to compare the mean values among the different groups. Differences were considered significant whenever the p-value was P ≤ 0.05. From the different results evaluated it was observed that in handgrip test, groups 2, 3 and 5 with hanging time of 11.7±1.18, 13.55±1.37 and 11.5±0.52 respectively were significantly different ≤ 0.05 from the control with 6.6±1.13 second hanging time. Beam walking had a dose dependent slowness in walking across the beam among the treated groups as compared with the control. Inverted screen test has group 3 with the highest performance time of 20.55±8.42 which was significantly higher than the control with 8.4±1.98 seconds This result reveals that the administration of O.G. have significant effect on the cognitive, coordination and neuromuscular functions of the albino rats. It also shows a window of effectiveness of the extract on neuromuscular activities.

Conscious awareness and memory systems in the brain.

The term "memory" typically refers to conscious retrieval of events and experiences from our past, but experience can also change our behaviour without corresponding awareness of the learning process or the associated outcome. Based primarily on early neuropsychological work, theoretical perspectives have distinguished between conscious memory, said to depend critically on structures in the medial temporal lobe (MTL), and a collection of performance-based memories that do not. The most influential of these memory systems perspectives, the declarative memory theory, continues to be a mainstay of scientific work today despite mounting evidence suggesting that contributions of MTL structures go beyond the kinds or types of memory that can be explicitly reported. Consistent with these reports, more recent perspectives have focused increasingly on the processing operations supported by particular brain regions and the qualities or characteristics of resulting representations whether memory is expressed with or without awareness. These alternatives to the standard model generally converge on two key points. First, the hippocampus is critical for relational memory binding and representation even without awareness and, second, there may be little difference between some types of priming and explicit, familiarity-based recognition. Here, we examine the evolution of memory systems perspectives and critically evaluate scientific evidence that has challenged the status quo. Along the way, we highlight some of the challenges that researchers encounter in the context of this work, which can be contentious, and describe innovative methods that have been used to examine unconscious memory in the lab. This article is categorized under: Psychology > Memory Psychology > Theory and Methods Philosophy > Consciousness.

BDNF Val66Met polymorphism is associated with consolidation of episodic memory during sleep

The brain-derived neurotrophic factor (BDNF) is an essential regulator of synaptic plasticity, a candidate neurobiological mechanism underlying learning and memory. A functional polymorphism in the BDNF gene, Val66Met (rs6265), has been linked to memory and cognition in healthy individuals and clinical populations. Sleep contributes to memory consolidation, yet information about the possible role of BDNF in this process is scarce. To address this question, we investigated the relationship between the BDNF Val66Met genotype and consolidation of episodic declarative and procedural (motor) non-declarative memories in healthy adults. The carriers of Met66 allele, as compared with Val66 homozygotes, showed stronger forgetting overnight (24 h after encoding), but not over shorter time (immediately or 20 min after word list presentation). There was no effect of Val66Met genotype on motor learning. These data suggest that BDNF plays a role in neuroplasticity underlying episodic memory consolidation during sleep.

A Single Session of Mindfulness Meditation Expedites Immediate Motor Memory Consolidation to Improve Wakeful Offline Learning

Posttraining meditation has been shown to promote wakeful memory stabilization of explicit motor sequence information in learners who are experienced meditators. We investigated the effect of single-session mindfulness meditation on wakeful and sleep-dependent forms of implicit motor memory consolidation in meditation naïve adults. Immediately after training with a target implicit motor sequence, participants (N = 20, eight females, 23.9 ± 3.3 years) completed either a 10-min mindfulness meditation (N = 10) or a control listening task before exposure to task interference induced by training with a novel implicit sequence. Target sequence performance was tested following 5-hr wakeful and 15-hr postsleep periods. Bayesian inference was applied to group comparisons of mean reaction time (RT) changes across training, interference, wakeful, and postsleep timepoints. Relative to control conditions, posttraining meditation reduced RT slowing between target sequence training and interference sequence introduction (BF10 [Bayes factors] = 6.61) and supported RT performance gains over the wakeful period (BF10 = 8.34). No group differences in postsleep RT performance were evident (BF10 = 0.38). These findings illustrate that posttraining mindfulness meditation expedites wakeful, but not sleep-dependent, offline learning with implicit motor sequences. Previous meditation experience is not required to obtain wakeful consolidation gains from posttraining mindfulness meditation.

Collective Trauma, Implicit Memories, the Body, and Active Imagination in Jungian Analysis.

This presentation attempts to show the healing potential underlying the inclusion of the patient's body in the analytic process, while honouring and revisiting the understanding of the psyche-body connection described by Jung in his early work. In addition, the author offers reflections on the impact of collective trauma whose aftermath, among others, has been the disappearance of thousands of people, consequently breaking the family genealogy, leaving hundreds of children stripped of their roots and true identity. Referencing clinical material, the author describes how the process of translation and integration-from the sensory-perceptual to the conceptual-symbolic-can be halted on account of collective trauma occurring at an early stage in development. Moreover, it is shown how the potential of the archetype or image schema, linked to the somatic-affective early experiences encoded as implicit memories, can be recovered, when Embodied Active Imagination is included in the analytic work. The patient's bodily gestures and somatic experience may bridge the gap between the preverbal-implicit knowledge and the emergence of emotions and images that allow for the creation of a new symbolic narrative.

Neural correlates of sleep-induced benefits on traumatic memory processing.

Recent findings indicate that sleep after trauma compared to sleep loss inhibits intrusive memory development, possibly by promoting adequate memory consolidation and integration. However, the underlying neural mechanisms are still unknown. Here, we examined the neural correlates underlying the effects of sleep on traumatic memory development in 110 healthy participants using a trauma film paradigm and an implicit memory task with fMRI recordings in a between-subjects design. To further facilitate memory integration, we used targeted memory reactivation (TMR) to reactivate traumatic memories during sleep. We found that sleep (i.e., nap) compared to wakefulness reduced the number of intrusive traumatic memories for the experimental trauma groups. TMR during sleep only descriptively reduced the intrusions further. On the level of brain activity, increased activity in the anterior and posterior cingulate cortex, retrosplenial cortex and precuneus was found in the experimental trauma group compared to the control group after wakefulness. After sleep, on the other hand, these findings could not be found in the experimental trauma groups compared to the control group. Sleep compared to wakefulness increased activity in the cerebellum, fusiform gyrus, inferior temporal lobe, hippocampus, and amygdala during implicit retrieval of trauma memories in the experimental trauma groups. Activity in the hippocampus and the amygdala predicted subsequent intrusions. Results demonstrate the beneficial behavioral and neural effects of sleep after experimental trauma and provide indications for early neural predictor factors. This study has implications for understanding the important role of sleep for personalized treatment and prevention in posttraumatic stress disorder.

Devouring and Asphyxia: Symptoms of a Cultural Complex in Present Times.

The article discusses dominance and oppression in society due to cultural complexes filled with collective memories of destructiveness and perpetration, implicit memories which have remained repressed. Individual personal complexes and traumas are intertwined with traumatizing historical circumstances, setting up pairs of perpetrator and victim. The metaphors of devouring and asphyxiation are used to denote interpersonal and group relationships in which feelings of imprisonment, suffocating anxiety and expulsion are predominant, all of which leads to painful projections and introjections, dissociation and suffering. Asphyxiating death symbolizes not only environmental devastation by fire, the pandemic and the plague, but is also seen as a symptom of acute anxiety in modern times. Devouring stands for the annulment of the objectified Other in a patriarchal society best revealed in fratricidal struggles, the oppression of women and, ultimately, wars.

What sticks after statistical learning: The persistence of implicit versus explicit memory traces

Statistical learning is a powerful mechanism that extracts even subtle regularities from our information-dense worlds. Recent theories argue that statistical learning can occur through multiple mechanisms—both the conventionally assumed automatic process that precipitates unconscious learning, and an attention-dependent process that brings regularities into conscious awareness. While this view has gained popularity, there are few empirical dissociations of the hypothesized implicit and explicit forms of statistical learning. Here we provide strong evidence for this dissociation in two ways. First, we show in healthy adults (N = 60) that implicit and explicit traces have divergent consolidation trajectories, with implicit knowledge of structure strengthened over a 24-h period, while precise explicit representations tend to decay. Second, we demonstrate that repeated testing strengthens the retention of explicit representations but that implicit statistical learning is uninfluenced by testing. Together these dissociations provide much needed support for the reconceptualization of statistical learning as a multi-component construct.

The Eucharist, dementia, and time

ABSTRACT Time is not sequential only. This essay considers the simultaneousness of times as we experience it in the Eucharist, the re-enacting of the past and the anticipation of our future wholeness in the celebration of the present moment. It shows that this simultaneousness can be linked to the way in which people with dementia relate to time. When people with dementia get mixed up about time this is a symptom of a serious disease. But there may be other aspects to it. Their re-enacting the past may be valid behaviour. Their low future orientation may make it possible to value the present more. Losing cognitive memory does not mean that there is no memory at all. Involuntary memory or implicit memory is still available even after cognitive recall goes. This paper postulates that this is a memory which points to God’s grace and shows that people with dementia can help us to see the Eucharist from a different perspective. They remind us of our own fragility and dependence on grace and make us aware that Eucharistic remembrance is involuntary, too. If we are willing to learn from them we may approach and celebrate the Eucharist in a less cognitive way

P-26 Effects of combining non-invasive brain stimulation and cognitive training to improve implicit memory in healthy versus cognitively impaired elderly people

P-26 Effects of combining non-invasive brain stimulation and cognitive training to improve implicit memory in healthy versus cognitively impaired elderly people

Proto-Lexicon Size and Phonotactic Knowledge are Linked in Non-Māori Speaking New Zealand Adults

Most people in New Zealand are exposed to the Māori language on a regular basis, but do not speak it. It has recently been claimed that this exposure leads them to create a large proto-lexicon, consisting of implicit memories of words and word parts, without semantic knowledge. This yields sophisticated phonotactic knowledge (Oh et al., 2020). This claim was supported by two tasks in which Non-Māori-Speaking New Zealanders: (i) Distinguished real words from phonotactically matched non-words, suggesting lexical knowledge; (ii) Gave wellformedness ratings of non-words almost indistinguishable from those of fluent Māori speakers, demonstrating phonotactic knowledge.Oh et al. (2020) ran these tasks on separate participants. While they hypothesised that phonotactic and lexical knowledge derived from the proto-lexicon, they did not establish a direct link between them. We replicate the two tasks, with improved stimuli, on the same set of participants. We find a statistically significant link between the tasks: Participants with a larger proto-lexicon (evidenced by performance in the Word Identification Task) show greater sensitivity to phonotactics in the Wellformedness Rating Task. This extends the previously reported results, increasing the evidence that exposure to a language you do not speak can lead to large-scale implicit knowledge about that language.

Intracranial Self-stimulation of the Medial Forebrain Bundle Ameliorates Memory Disturbances and Pathological Hallmarks in an Alzheimer’s Disease Model by Intracerebral Administration of Amyloid-β in Rats

No curative or fully effective treatments are currently available for Alzheimer’s disease (AD), the most common form of dementia. Electrical stimulation of deep brain areas has been proposed as a novel neuromodulatory therapeutic approach. Previous research from our lab demonstrates that intracranial self-stimulation (ICSS) targeting medial forebrain bundle (MFB) facilitates explicit and implicit learning and memory in rats with age or lesion-related memory impairment. At a molecular level, MFB-ICSS modulates the expression of plasticity and neuroprotection-related genes in memory-related brain areas. On this basis, we suggest that MFB could be a promising stimulation target for AD treatment. In this study, we aimed to assess the effects of MFB-ICSS on both explicit memory as well as the levels of neuropathological markers ptau and drebrin (DBN) in memory-related areas, in an AD rat model obtained by Aβ icv-injection. A total of 36 male rats were trained in the Morris water maze on days 26–30 after Aβ injection and tested on day 33. Results demonstrate that this Aβ model displayed spatial memory impairment in the retention test, accompanied by changes in the levels of DBN and ptau in lateral entorhinal cortex and hippocampus, resembling pathological alterations in early AD. Administration of MFB-ICSS treatment consisting of 5 post-training sessions to AD rats managed to reverse the memory deficits as well as the alteration in ptau and DBN levels. Thus, this paper reports both cognitive and molecular effects of a post-training reinforcing deep brain stimulation procedure in a sporadic AD model for the first time.

Early different cognitive processes evoked by carnival vs. general promotions when shopping online: An ERPs study.

The booming development of online shopping has intensified market competition. In addition to general sales promotions, online shopping has introduced new changes including artificial carnival promotions. This study aims to investigate cognitive processes to an unknown e-commerce platform after exposure to carnival and general promotion activities using event-related potentials. Thirty-three participants were recruited in this study to probe how consumers perceive carnival and general promotion information using event-related potentials (ERPs). Carnival or general promotion posters were presented first, then an unknown e-commerce platform brand was presented in the second stage, at which time the subjects' cognitive process to the brand were observed in an implicit paradigm. The results showed that after priming with carnival promotion posters, the unknown e-commerce platform stimuli elicited larger P2 and N2 components than were observed after the presentation of general promotion posters; however, the P3 component did not show a significant difference. These findings indicate that the target identification and cognitive control mechanism with regard to an unknown e-commerce platform are likely influenced by the implicit memory of different promotion activities when shopping online. The results suggest that ERP components may have the potential to be employed as indices to estimate the effectiveness of promotion methods for an unknown brand.

The Effect of Tablet App with Different Learning Content on Preschoolers’ Implicit Memory Development: Numbers and Literacy

With the development of new technology, products such as tablets have begun playing an increasingly important role in early childhood education. This study investigated the effect of an educational tablet app based teaching method and a conventional teaching method on young children’s implicit memory. Participants (N = 123) aged between aged three to five from a preschool were divided into four groups, the number cognition and reading comprehension experimental and control groups. The experimental groups underwent using the educational tablet apps for 2 months, while the control group followed regular teaching activities. Participants’ implicit memory were analyzed before and after the training. Among the four groups, the implicit memory of children in the number cognition tablet instruction group improved significantly, followed by the reading comprehension conventional group. The result reinforces previous findings that learning contents presented by different teaching methods could promote young children’s implicit memory development.