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1.
Behav Brain Sci ; 47: e169, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39311504

RESUMEN

This commentary examines the synergy between meta-learned models of cognition and integrative learning in enhancing animal and human learning outcomes. It highlights three integrative learning modes - holistic integration of parts, top-down reasoning, and generalization with in-depth analysis - and their alignment with meta-learned models of cognition. This convergence promises significant advances in educational practices, artificial intelligence, and cognitive neuroscience, offering a novel perspective on learning and cognition.


Asunto(s)
Cognición , Aprendizaje , Humanos , Animales , Cognición/fisiología , Aprendizaje/fisiología , Inteligencia Artificial , Modelos Psicológicos , Generalización Psicológica/fisiología
2.
Adv Child Dev Behav ; 67: 31-69, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39260907

RESUMEN

Identifying the origins of moral sensitivities, and their elaboration, within infancy and early childhood is a challenging task, given inherent limitations in infants' behavior. Here, I argue for a multi-pronged, multi-method approach that involves cleaving the moral response at its joints. Specifically, I chart the emergence of infants' moral expectations, evaluations, generalization and enforcement, demonstrating that while many moral sensitivities are present in the second year of life, these sensitivities are closely aligned with, and likely driven by, infants' everyday experience. Moreover, qualitative differences exist between the moral responses that are present in infancy and those of later childhood, particularly in terms of enforcement (i.e., a lack of punishment in infancy). These findings set the stage for addressing outstanding critical questions regarding moral development, that include identifying discrete causal inputs to early moral cognition, identifying whether moral cognition is distinct from social cognition early in life, and explaining gaps that exist between moral cognition and moral behavior in development.


Asunto(s)
Generalización Psicológica , Desarrollo Moral , Humanos , Lactante , Principios Morales , Desarrollo Infantil , Normas Sociales , Cognición Social , Conducta del Lactante , Preescolar , Castigo
3.
Cogn Res Princ Implic ; 9(1): 57, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39218993

RESUMEN

Humans are often tasked to remember new faces so that they can recognize the faces later in time. Previous studies found that memory reports for basic visual features (e.g., colors and shapes) are susceptible to systematic distortions as a result of comparison with new visual input, especially when the input is perceived as similar to the memory. The current study tested whether this similarity-induced memory bias (SIMB) would also occur with more complex face stimuli. The results showed that faces that are just perceptually encoded into visual working memory as well as retrieved from visual long-term memory are also susceptible to SIMB. Furthermore, once induced, SIMB persisted over time across cues through which the face memory was accessed for memory report. These results demonstrate the generalizability of SIMB to more complex and practically relevant stimuli, and thus, suggest potential real-world implications.


Asunto(s)
Reconocimiento Facial , Memoria a Corto Plazo , Humanos , Reconocimiento Facial/fisiología , Femenino , Masculino , Adulto Joven , Adulto , Memoria a Corto Plazo/fisiología , Generalización Psicológica/fisiología , Adolescente , Memoria a Largo Plazo/fisiología
4.
Neural Netw ; 179: 106629, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39153401

RESUMEN

Domain Generalization (DG) focuses on the Out-Of-Distribution (OOD) generalization, which is able to learn a robust model that generalizes the knowledge acquired from the source domain to the unseen target domain. However, due to the existence of the domain shift, domain-invariant representation learning is challenging. Guided by fine-grained knowledge, we propose a novel paradigm Mask-Shift-Inference (MSI) for DG based on the architecture of Convolutional Neural Networks (CNN). Different from relying on a series of constraints and assumptions for model optimization, this paradigm novelly shifts the focus to feature channels in the latent space for domain-invariant representation learning. We put forward a two-branch working mode of a main module and multiple domain-specific sub-modules. The latter can only achieve good prediction performance in its own specific domain but poor predictions in other source domains, which provides the main module with the fine-grained knowledge guidance and contributes to the improvement of the cognitive ability of MSI. Firstly, during the forward propagation of the main module, the proposed MSI accurately discards unstable channels based on spurious classifications varying across domains, which have domain-specific prediction limitations and are not conducive to generalization. In this process, a progressive scheme is adopted to adaptively increase the masking ratio according to the training progress to further reduce the risk of overfitting. Subsequently, our paradigm enters the compatible shifting stage before the formal prediction. Based on maximizing semantic retention, we implement the domain style matching and shifting through the simple transformation through Fourier transform, which can explicitly and safely shift the target domain back to the source domain whose style is closest to it, requiring no additional model updates and reducing the domain gap. Eventually, the paradigm MSI enters the formal inference stage. The updated target domain is predicted in the main module trained in the previous stage with the benefit of familiar knowledge from the nearest source domain masking scheme. Our paradigm is logically progressive, which can intuitively exclude the confounding influence of domain-specific spurious information along with mitigating domain shifts and implicitly perform semantically invariant representation learning, achieving robust OOD generalization. Extensive experimental results on PACS, VLCS, Office-Home and DomainNet datasets verify the superiority and effectiveness of the proposed method.


Asunto(s)
Redes Neurales de la Computación , Humanos , Generalización Psicológica/fisiología , Algoritmos , Aprendizaje Automático
5.
Artículo en Inglés | MEDLINE | ID: mdl-39094926

RESUMEN

Foot-shock paradigms have provided valuable insights into the neurobiology of stress and fear conditioning. An extensive body of literature indicates that shock exposure can elicit both conditioned and unconditioned effects, although delineating between the two is a challenging task. This distinction holds crucial implications not only for the theoretical interpretation of fear conditioning, but also for properly evaluating putative preclinical models of post-traumatic stress disorder (PTSD) involving shock exposure. The characteristics of shocks (intensity and number) affect the strength of learning, but how these characteristics interact to influence conditioned and unconditioned consequences of shocks are poorly known. In this study, we aimed to investigate in adult male rats the impact of varying shock number and intensity on the endocrine and behavioral response to contextual fear conditioning and fear generalization to a novel environment markedly distinct from the shock context (i.e., fear generalization). Classical biological markers of stress (i.e., ACTH, corticosterone, and prolactin) were sensitive to manipulations of shock parameters, whereas these parameters had a limited effect on contextual fear conditioning (evaluated by freezing and distance traveled). In contrast, behavior in different novel contexts (fear generalization) was specifically sensitive to shock intensity. Notably, altered behavior in novel contexts markedly improved, but not completely normalized after fear extinction, hypoactivity apparently being the result of both conditioned and unconditioned effects of foot-shock exposure. The present results will contribute to a better understanding of shock exposure as a putative animal model of PTSD.


Asunto(s)
Hormona Adrenocorticotrópica , Condicionamiento Clásico , Corticosterona , Electrochoque , Miedo , Generalización Psicológica , Animales , Masculino , Miedo/fisiología , Miedo/psicología , Generalización Psicológica/fisiología , Condicionamiento Clásico/fisiología , Corticosterona/sangre , Ratas , Hormona Adrenocorticotrópica/sangre , Ratas Wistar
6.
BMC Psychol ; 12(1): 460, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39215348

RESUMEN

In contrast to conventional cognitive training paradigms, where learning effects are specific to trained parameters, playing action video games has been shown to produce broad enhancements in many cognitive functions. These remarkable generalizations challenge the conventional theory of generalization that learned knowledge can be immediately applied to novel situations (i.e., immediate generalization). Instead, a new "learning to learn" theory has recently been proposed, suggesting that these broad generalizations are attained because action video game players (AVGPs) can quickly acquire the statistical regularities of novel tasks in order to increase the learning rate and ultimately achieve better performance. Although enhanced learning rate has been found for several tasks, it remains unclear whether AVGPs efficiently learn task statistics and use learned task knowledge to guide learning. To address this question, we tested 34 AVGPs and 36 non-video game players (NVGPs) on a cue-response associative learning task. Importantly, unlike conventional cognitive tasks with fixed task statistics, in this task, cue-response associations either remain stable or change rapidly (i.e., are volatile) in different blocks. To complete the task, participants should not only learn the lower-level cue-response associations through explicit feedback but also actively estimate the high-level task statistics (i.e., volatility) to dynamically guide lower-level learning. Such a dual learning system is modelled using a hierarchical Bayesian learning framework, and we found that AVGPs indeed quickly extract the volatility information and use the estimated higher volatility to accelerate learning of the cue-response associations. These results provide strong evidence for the "learning to learn" theory of generalization in AVGPs. Taken together, our work highlights enhanced hierarchical learning of both task statistics and cognitive abilities as a mechanism underlying the broad enhancements associated with action video game play.


Asunto(s)
Juegos de Video , Humanos , Masculino , Femenino , Adulto Joven , Adulto , Aprendizaje por Asociación/fisiología , Aprendizaje , Señales (Psicología) , Generalización Psicológica
7.
Trends Hear ; 28: 23312165241275895, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39212078

RESUMEN

Auditory training can lead to notable enhancements in specific tasks, but whether these improvements generalize to untrained tasks like speech-in-noise (SIN) recognition remains uncertain. This study examined how training conditions affect generalization. Fifty-five young adults were divided into "Trained-in-Quiet" (n = 15), "Trained-in-Noise" (n = 20), and "Control" (n = 20) groups. Participants completed two sessions. The first session involved an assessment of SIN recognition and voice discrimination (VD) with word or sentence stimuli, employing combined fundamental frequency (F0) + formant frequencies voice cues. Subsequently, only the trained groups proceeded to an interleaved training phase, encompassing six VD blocks with sentence stimuli, utilizing either F0-only or formant-only cues. The second session replicated the interleaved training for the trained groups, followed by a second assessment conducted by all three groups, identical to the first session. Results showed significant improvements in the trained task regardless of training conditions. However, VD training with a single cue did not enhance VD with both cues beyond control group improvements, suggesting limited generalization. Notably, the Trained-in-Noise group exhibited the most significant SIN recognition improvements posttraining, implying generalization across tasks that share similar acoustic conditions. Overall, findings suggest training conditions impact generalization by influencing processing levels associated with the trained task. Training in noisy conditions may prompt higher auditory and/or cognitive processing than training in quiet, potentially extending skills to tasks involving challenging listening conditions, such as SIN recognition. These insights hold significant theoretical and clinical implications, potentially advancing the development of effective auditory training protocols.


Asunto(s)
Estimulación Acústica , Señales (Psicología) , Generalización Psicológica , Ruido , Percepción del Habla , Humanos , Masculino , Femenino , Adulto Joven , Percepción del Habla/fisiología , Ruido/efectos adversos , Adulto , Reconocimiento en Psicología , Enmascaramiento Perceptual , Adolescente , Acústica del Lenguaje , Calidad de la Voz , Aprendizaje Discriminativo/fisiología , Voz/fisiología
8.
Eat Behav ; 54: 101902, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38971023

RESUMEN

The benefit of food-specific inhibition training on modulating food valuation and eating behaviors has been established, but generalization to untrained foods is seldomly examined. This study investigated whether stimulus variability and practice order, found to effect generalization in motor learning, can improve generalization following food-specific inhibition training. Ninety-three young adults practiced the Go/No-Go task online in three training conditions: 1) Constant (N = 30): inhibition practiced on one food stimulus; 2) Variable-Blocked (N = 32): inhibition practiced on 6 food stimuli, each in a separate block; and 3) Variable-Random (N = 31): inhibition practiced on 6 food stimuli in random order. Consistent with our hypothesis, the Variable-Random group showed better generalization of inhibition to untrained foods than the Constant and the Variable-Blocked groups immediately after training, demonstrating the benefit of stimulus variability and random practice order. This effect was not present 24 h after training. The Variable-Random group also showed decreased desire to eat untrained foods, exhibiting generalization of food devaluation. However, this effect was only present 24 h after training. The Constant group showed increased desire to eat untrained foods immediately and 24 h after training. The Variable-Blocked group did not differ from either group in the desire to eat to untrained foods, suggesting that random order is important for exposing the benefit of variability. The findings illustrate that presenting various training items in random order can improve generalization of food-specific inhibition training. However, inconsistencies found in the timing of generalization effects and modest effect sizes warrant additional investigation into generalization principles of food-specific inhibition training.


Asunto(s)
Generalización Psicológica , Inhibición Psicológica , Humanos , Femenino , Masculino , Generalización Psicológica/fisiología , Adulto Joven , Adulto , Conducta Alimentaria/psicología , Alimentos , Adolescente
9.
Neural Netw ; 179: 106561, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39084171

RESUMEN

Person re-identification (ReID) has made good progress in stationary domains. The ReID model must be retrained to adapt to new scenarios (domains) as they emerge unexpectedly, which leads to catastrophic forgetting. Continual learning trains the model in the order of domain emergence to alleviate catastrophic forgetting. However, generalization ability of the model is still limited due to the distribution difference between training and testing domains. To address the above problem, we propose the generalized continual person re-Identification (GCReID) model to continuously train an anti-forgetting and generalizable model. We endeavor to increase the diversity of samples by prior to simulate unseen domains. Meta-train and meta-test are adopted to enhance generalization of the model. Universal knowledge extracted from all seen domains and the simulated domains is stored in a set of feature embeddings. The knowledge is continually updated and applied to guide meta-train and meta-test via a graph attention network. Extensive experiments on 12 benchmark datasets and comparisons with 6 representative models demonstrate the effectiveness of the proposed model GCReID in enhancing generalization performance on unseen domains and alleviating catastrophic forgetting of seen domains. The code will be available at https://github.com/DFLAG-NEU/GCReID if our work is accepted.


Asunto(s)
Redes Neurales de la Computación , Humanos , Conocimiento , Generalización Psicológica , Aprendizaje , Identificación Biométrica/métodos , Aprendizaje Automático , Algoritmos
10.
Behav Brain Res ; 472: 115146, 2024 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-39009189

RESUMEN

Mental imagery may represent a weaker form of perception and, thus, mental images may be more ambiguous than visual percepts. If correct, the acquisition of fear would be less specific for imagined fears in comparison to perceptual fears, perhaps facilitating broader fear generalization. To test this idea, a two-day differential fear conditioning experiment (N = 98) was conducted. On day one, two groups of participants underwent differential fear conditioning such that a specific Gabor patch orientation (CS+) was paired with mild shocks (US) while a second Gabor patch of orthogonal orientation (CS-) was never paired with shock. Critically, one group imagined the Gabor patches and the other group was visually presented the Gabor patches. Next, both groups were presented visual Gabor patches of similar orientations (GCS) to the CS+. On day two, to assess the persistence of imagined fear, participants returned to the lab and were tested on the GCS devoid of shock. For day one, in contrast to our primary hypothesis, both self-report and skin conductance response measures did not show a significant interaction between the GCS and groups. On day two, both measures demonstrated a persistence of imagined fear, without US delivery. Taken together, rather than demonstrating an overgeneralization effect, the results from this study suggest that imagery-based fear conditioning generalizes to a similar extent as perceptually acquired fear conditioning. Further, the persistence of imagery-based fear may have unique extinction qualities in comparison to perceptual-based fear.


Asunto(s)
Condicionamiento Clásico , Miedo , Respuesta Galvánica de la Piel , Generalización Psicológica , Imaginación , Humanos , Miedo/fisiología , Imaginación/fisiología , Masculino , Femenino , Adulto Joven , Generalización Psicológica/fisiología , Respuesta Galvánica de la Piel/fisiología , Condicionamiento Clásico/fisiología , Adulto , Adolescente
11.
Nat Neurosci ; 27(9): 1656-1667, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39075326

RESUMEN

Cognitive neuroscience seeks generalizable theories explaining the relationship between behavioral, physiological and mental states. In pursuit of such theories, we propose a theoretical and empirical framework that centers on understanding task demands and the mutual constraints they impose on behavior and neural activity. Task demands emerge from the interaction between an agent's sensory impressions, goals and behavior, which jointly shape the activity and structure of the nervous system on multiple spatiotemporal scales. Understanding this interaction requires multitask studies that vary more than one experimental component (for example, stimuli and instructions) combined with dense behavioral and neural sampling and explicit testing for generalization across tasks and data modalities. By centering task demands rather than mental processes that tasks are assumed to engage, this framework paves the way for the discovery of new generalizable concepts unconstrained by existing taxonomies, and moves cognitive neuroscience toward an action-oriented, dynamic and integrated view of the brain.


Asunto(s)
Neurociencia Cognitiva , Humanos , Neurociencia Cognitiva/métodos , Encéfalo/fisiología , Generalización Psicológica/fisiología , Cognición/fisiología
12.
Proc Natl Acad Sci U S A ; 121(28): e2314511121, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38968113

RESUMEN

Humans and animals routinely infer relations between different items or events and generalize these relations to novel combinations of items. This allows them to respond appropriately to radically novel circumstances and is fundamental to advanced cognition. However, how learning systems (including the brain) can implement the necessary inductive biases has been unclear. We investigated transitive inference (TI), a classic relational task paradigm in which subjects must learn a relation ([Formula: see text] and [Formula: see text]) and generalize it to new combinations of items ([Formula: see text]). Through mathematical analysis, we found that a broad range of biologically relevant learning models (e.g. gradient flow or ridge regression) perform TI successfully and recapitulate signature behavioral patterns long observed in living subjects. First, we found that models with item-wise additive representations automatically encode transitive relations. Second, for more general representations, a single scalar "conjunctivity factor" determines model behavior on TI and, further, the principle of norm minimization (a standard statistical inductive bias) enables models with fixed, partly conjunctive representations to generalize transitively. Finally, neural networks in the "rich regime," which enables representation learning and improves generalization on many tasks, unexpectedly show poor generalization and anomalous behavior on TI. We find that such networks implement a form of norm minimization (over hidden weights) that yields a local encoding mechanism lacking transitivity. Our findings show how minimal statistical learning principles give rise to a classical relational inductive bias (transitivity), explain empirically observed behaviors, and establish a formal approach to understanding the neural basis of relational abstraction.


Asunto(s)
Generalización Psicológica , Humanos , Generalización Psicológica/fisiología , Aprendizaje/fisiología , Cognición/fisiología , Modelos Teóricos , Encéfalo/fisiología
13.
Neurobiol Learn Mem ; 213: 107960, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39004160

RESUMEN

Labilization-reconsolidation, which relies on retrieval, has been considered an opportunity to attenuate the negative aspects of traumatic memories. A therapeutic strategy based on reconsolidation blockade is deemed more effective than current therapies relying on memory extinction. Nevertheless, extremely stressful memories frequently prove resistant to this process. Here, after inducing robust fear memory in mice through strong fear conditioning, we examined the possibility of rendering it susceptible to pharmacological modulation based on the degree of generalized fear (GF). To achieve this, we established an ordered gradient of GF, determined by the perceptual similarity between the associated context (CA) and non-associated contexts (CB, CC, CD, and CE) to the aversive event. We observed that as the exposure context became less similar to CA, the defensive pattern shifted from passive to active behaviors in both male and female mice. Subsequently, in conditioned animals, we administered propranolol after exposure to the different contexts (CA, CB, CC, CD or CE). In males, propranolol treatment resulted in reduced freezing time and enhanced risk assessment behaviors when administered following exposure to CA or CB, but not after CC, CD, or CE, compared to the control group. In females, a similar change in behavioral pattern was observed with propranolol administered after exposure to CC, but not after the other contexts. These results highlight the possibility of indirectly manipulating a robust contextual fear memory by controlling the level of generalization during recall. Additionally, it was demonstrated that the effect of propranolol on reconsolidation would not lead to a reduction in fear memory per se, but rather to its reorganization resulting in greater behavioral flexibility (from passive to active behaviors). Finally, from a clinical viewpoint, this would be of considerable relevance since following this strategy could make the treatment of psychiatric disorders associated with traumatic memory formation more effective and less stressful.


Asunto(s)
Condicionamiento Clásico , Miedo , Propranolol , Miedo/efectos de los fármacos , Miedo/fisiología , Animales , Masculino , Propranolol/farmacología , Femenino , Ratones , Condicionamiento Clásico/efectos de los fármacos , Consolidación de la Memoria/efectos de los fármacos , Consolidación de la Memoria/fisiología , Ratones Endogámicos C57BL , Memoria/efectos de los fármacos , Memoria/fisiología , Generalización Psicológica/efectos de los fármacos , Generalización Psicológica/fisiología , Extinción Psicológica/efectos de los fármacos
14.
J Psychopharmacol ; 38(7): 672-682, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39068641

RESUMEN

BACKGROUND: The neurotransmitter dopamine plays an important role in the processing of emotional memories, and prior research suggests that dopaminergic manipulations immediately after fear learning can affect the retention and generalization of acquired fear. AIMS: The current study focuses specifically on the role of dopamine D2 receptors (D2Rs) regarding fear generalization in adult, male Wistar rats, and aims to replicate previous findings in mice. METHODS: In a series of five experiments, D2R (ant)agonists were injected systemically, immediately after differential cued fear conditioning (CS+ followed by shock, CS- without shock). All five experiments involved the administration of the D2R agonist quinpirole at different doses versus saline (n = 12, 16, or 44 rats/group). In addition, one of the studies administered the D2R antagonist raclopride (n = 12). One day later, freezing during the CS+ and CS- was assessed. RESULTS: We found no indications for an effect of quinpirole or raclopride on fear generalization during this drug-free test. Importantly, and contradicting earlier research in mice, the evidence for the absence of an effect of D2R agonist quinpirole (1 mg/kg) on fear generalization was substantial according to Bayesian analyses and was observed in a highly powered experiment (N = 87). We did find acute behavioral effects in line with the literature, for both quinpirole and raclopride in a locomotor activity test. CONCLUSION: In contrast with prior studies in mice, we have obtained evidence against a preventative effect of post-training D2R agonist quinpirole administration on subsequent fear generalization in rats.


Asunto(s)
Condicionamiento Clásico , Agonistas de Dopamina , Miedo , Generalización Psicológica , Quinpirol , Racloprida , Ratas Wistar , Receptores de Dopamina D2 , Animales , Miedo/efectos de los fármacos , Masculino , Receptores de Dopamina D2/agonistas , Receptores de Dopamina D2/metabolismo , Quinpirol/farmacología , Agonistas de Dopamina/farmacología , Ratas , Generalización Psicológica/efectos de los fármacos , Racloprida/farmacología , Condicionamiento Clásico/efectos de los fármacos , Antagonistas de los Receptores de Dopamina D2/farmacología
15.
Cogn Sci ; 48(7): e13479, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38980965

RESUMEN

Gestures-hand movements that accompany speech and express ideas-can help children learn how to solve problems, flexibly generalize learning to novel problem-solving contexts, and retain what they have learned. But does it matter who is doing the gesturing? We know that producing gesture leads to better comprehension of a message than watching someone else produce gesture. But we do not know how producing versus observing gesture impacts deeper learning outcomes such as generalization and retention across time. Moreover, not all children benefit equally from gesture instruction, suggesting that there are individual differences that may play a role in who learns from gesture. Here, we consider two factors that might impact whether gesture leads to learning, generalization, and retention after mathematical instruction: (1) whether children see gesture or do gesture and (2) whether a child spontaneously gestures before instruction when explaining their problem-solving reasoning. For children who spontaneously gestured before instruction, both doing and seeing gesture led to better generalization and retention of the knowledge gained than a comparison manipulative action. For children who did not spontaneously gesture before instruction, doing gesture was less effective than the comparison action for learning, generalization, and retention. Importantly, this learning deficit was specific to gesture, as these children did benefit from doing the comparison manipulative action. Our findings are the first evidence that a child's use of a particular representational format for communication (gesture) directly predicts that child's propensity to learn from using the same representational format.


Asunto(s)
Gestos , Aprendizaje , Solución de Problemas , Humanos , Femenino , Masculino , Matemática , Niño , Preescolar , Generalización Psicológica/fisiología
16.
PLoS Biol ; 22(7): e3002679, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38995985

RESUMEN

Over-generalized fear is a maladaptive response to harmless stimuli or situations characteristic of posttraumatic stress disorder (PTSD) and other anxiety disorders. The dorsal dentate gyrus (dDG) contains engram cells that play a crucial role in accurate memory retrieval. However, the coordination mechanism of neuronal subpopulations within the dDG network during fear generalization is not well understood. Here, with the Tet-off system combined with immunostaining and two-photon calcium imaging, we report that dDG fear engram cells labeled in the conditioned context constitutes a significantly higher proportion of dDG neurons activated in a similar context where mice show generalized fear. The activation of these dDG fear engram cells encoding the conditioned context is both sufficient and necessary for inducing fear generalization in the similar context. Activities of mossy cells in the ventral dentate gyrus (vMCs) are significantly suppressed in mice showing fear generalization in a similar context, and activating the vMCs-dDG pathway suppresses generalized but not conditioned fear. Finally, modifying fear memory engrams in the dDG with "safety" signals effectively rescues fear generalization. These findings reveal that the competitive advantage of dDG engram cells underlies fear generalization, which can be rescued by activating the vMCs-dDG pathway or modifying fear memory engrams, and provide novel insights into the dDG network as the neuronal basis of fear generalization.


Asunto(s)
Giro Dentado , Miedo , Neuronas , Animales , Miedo/fisiología , Giro Dentado/fisiología , Ratones , Masculino , Neuronas/fisiología , Neuronas/metabolismo , Ratones Endogámicos C57BL , Condicionamiento Clásico/fisiología , Memoria/fisiología , Generalización Psicológica/fisiología
17.
J Mot Behav ; 56(5): 642-653, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38989887

RESUMEN

Structural learning is characterized by facilitated adaptation following training on a set of sensory perturbations all belonging to the same structure (e.g., 'visuomotor rotations'). This generalization of learning is a core feature of the motor system and is often studied in the context of interlimb transfer. However, such transfer has only been demonstrated when participants learn to counter a specific perturbation in the sensory feedback of their movements; we determined whether structural learning in one limb generalized to the contralateral limb. We trained 13 participants to counter random visual feedback rotations between +/-90 degrees with the right hand and subsequently tested the left hand on a fixed rotation. The structural training group showed faster adaptation in the left hand in both feedforward and feedback components of reaching compared to 13 participants who trained with veridical reaching, with lower initial reaching error, and straighter, faster, and smoother movements than in the control group. The transfer was ephemeral - benefits were confined to roughly the first 20 trials. The results demonstrate that the motor system can extract invariant properties of seemingly random environments in one limb, and that this information can be accessed by the contralateral limb.


Asunto(s)
Adaptación Fisiológica , Lateralidad Funcional , Desempeño Psicomotor , Humanos , Masculino , Desempeño Psicomotor/fisiología , Femenino , Adulto , Adaptación Fisiológica/fisiología , Lateralidad Funcional/fisiología , Retroalimentación Sensorial/fisiología , Aprendizaje/fisiología , Generalización Psicológica/fisiología , Transferencia de Experiencia en Psicología/fisiología , Adulto Joven , Rotación , Movimiento/fisiología , Mano/fisiología
18.
Artículo en Inglés | MEDLINE | ID: mdl-38874309

RESUMEN

OBJECTIVES: The objectives of this project were to: (1) examine the relationship between the number of biological children and hippocampal-dependent cognitive performance among older African American women and (2) determine the influence of socioeconomic status (i.e., age, education, marital status, median household income), if any, on this relationship. METHODS: A total of 146 cognitively unimpaired African American women aged 60 and older were recruited from the greater Newark area and reported their number of biological children, marital status, educational level, and age. We retrieved median household income from census tract data based on the participants' addresses. Participants' cognitive performance was assessed using the Rey Auditory Verbal Learning Test (RAVLT) long delay recall and a Rutgers generalization task (Concurrent Discrimination and Transfer Task). RESULTS: As the number of biological children a woman has had increases, the number of generalization errors also increased, indicating poorer hippocampal-dependent cognitive performance when controlling for age, education, marital status, and median household income. There was no significant relationship between the number of children and performance on a standardized neuropsychological measure of episodic memory (RAVLT), although education was a significant covariate. DISCUSSION: Generalization tasks may better capture early changes in cognitive performance in older African American women who have had children than standardized neuropsychological assessments. This finding may be explained by the fluctuations in estrogen associated with having children. Future studies should explore how these findings can be applied to protecting cognitive function and preventing Alzheimer's disease in older African American women who have had children.


Asunto(s)
Negro o Afroamericano , Generalización Psicológica , Paridad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Persona de Mediana Edad , Negro o Afroamericano/psicología , Hipocampo , Memoria Episódica , Pruebas Neuropsicológicas
19.
Behav Brain Res ; 470: 115078, 2024 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-38825020

RESUMEN

Safety behaviors are responses that can reduce or even prevent an expected threat. Moreover, empirical studies have shown that using safety behaviors to a learnt safety stimulus can induce threat beliefs to it. No research so far has examined whether threat beliefs induced this way generalize to other novel stimuli related to the safety stimulus. Using a fear and avoidance conditioning model, the current study (n=116) examined whether threat beliefs induced by safety behaviors generalize to other novel generalization stimuli (GSs). Participants first acquired safety behaviors to a threat predicting conditioned stimulus (CSthreat). Safety behaviors could then be performed in response to one safe stimulus (CSsafeShift) but not to another (CSsafe). In a following generalization test, participants showed a significant but small increase in threat expectancies to GSs related to CSsafeShift compared to GSs related to CSsafe. Interestingly, the degree of safety behaviors used to the CSsafeShift predicted the subsequent increase in generalized threat expectancies, and this link was elevated in trait anxious individuals. The findings suggest that threat beliefs induced by unnecessary safety behaviors generalize to other related stimuli. This study provides a potential explanation for the root of threat belief acquisition to a wide range of stimuli or situations.


Asunto(s)
Reacción de Prevención , Condicionamiento Clásico , Miedo , Generalización Psicológica , Humanos , Miedo/fisiología , Masculino , Generalización Psicológica/fisiología , Femenino , Adulto Joven , Condicionamiento Clásico/fisiología , Reacción de Prevención/fisiología , Seguridad , Adulto , Ansiedad , Adolescente
20.
J Anxiety Disord ; 105: 102880, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38833961

RESUMEN

BACKGROUND: Pavlovian fear paradigms involve learning to associate cues with threat or safety. Aberrances in Pavlovian fear learning correlate with psychopathology, especially anxiety disorders. This study evaluated symptom dimensions of anxiety and depression in relation to Pavlovian fear acquisition and generalization. METHODS: 256 participants (70.31 % female) completed a Pavlovian fear acquisition and generalization paradigm at ages 18-19 and 21-22 years. Analyses focused on indices of learning (self-reported US expectancy, skin conductance). Multilevel models tested associations with orthogonal symptom dimensions (Anhedonia-Apprehension, Fears, General Distress) at each timepoint. RESULTS: All dimensions were associated with weaker acquisition of US expectancies at each timepoint. Fears was associated with overgeneralization only at age 21-22. General Distress was associated with overgeneralization only at age 18-19. Anhedonia-Apprehension was associated with overgeneralization at ages 18-19 and 21-22. CONCLUSIONS: Anhedonia-Apprehension disrupts Pavlovian fear acquisition and increases overgeneralization of fear. These effects may emerge during adolescence and remain into young adulthood. General Distress and Fears also contribute to overgeneralization of fear, but these effects may vary as prefrontal mechanisms of fear inhibition continue to develop during late adolescence. Targeting specific symptom dimensions, particularly Anhedonia-Apprehension, may decrease fear generalization and augment interventions built on Pavlovian principles, such as exposure therapy.


Asunto(s)
Anhedonia , Condicionamiento Clásico , Miedo , Respuesta Galvánica de la Piel , Generalización Psicológica , Humanos , Femenino , Miedo/fisiología , Miedo/psicología , Masculino , Adulto Joven , Adolescente , Condicionamiento Clásico/fisiología , Anhedonia/fisiología , Generalización Psicológica/fisiología , Respuesta Galvánica de la Piel/fisiología , Adulto , Ansiedad/psicología , Depresión/psicología
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