-
Prelimbic cortex ensembles promote appetitive learning-associated behavior Learn. Mem. (IF 2.0) Pub Date : 2024-01-01 Michelle Surets, Albit Caban-Murillo, Steve Ramirez
Memories of prior rewards bias our actions and future decisions. To determine the neural correlates of an appetitive associative learning task, we trained male mice to discriminate a reward-predicting cue over the course of 7 d. Encoding, recent recall, and remote recall were investigated to determine the areas of the brain recruited at each stage of learning. Using cFos as a proxy for neuronal activity
-
Evidence for novelty reward cross-cueing in the odor span task in rats: implications for odor-based reward-motivated tasks Learn. Mem. (IF 2.0) Pub Date : 2024-01-01 Timothy J. Onofrychuk, Aiden E. Glass, Quentin Greba, John G. Howland
The odor span task (OST) infers working memory capacity (WMC) by requiring rodents to discriminate between previously presented and session-novel odors to obtain a hidden food reward. Here, rats’ responses to session-novel odors and food rewards were assessed to determine whether rats use mitigating strategies in the OST. Rats accurately responded to session-novel odors but also reliably responded
-
Retrograde amnesia for the stress-induced impairment of extinction: time-dependent and not so forgotten Learn. Mem. (IF 2.0) Pub Date : 2024-01-01 James F. Briggs, Kaitlyn M. McMullen
We investigated whether retrograde amnesia for the stress-induced impairment of extinction retrieval shares similar characteristics with original acquisition memories. The first experiment demonstrated that cycloheximide administered shortly after a single restraint stress session alleviated the impairment of extinction retrieval but not when administered following a longer delay (i.e., the amnesia
-
Hippocampal motor memory network reorganization depends on familiarity, not time Learn. Mem. (IF 2.0) Pub Date : 2023-12-01 D. Gregory Sullens, Phuoc Nguyen, Kayla Gilley, Madison B. Wiffler, Melanie J. Sekeres
There is debate as to whether a time-dependent transformation of the episodic-like memory network is observed for nonepisodic tasks, including procedural motor memory. To determine how motor memory networks reorganize with time and practice, mice performed a motor task in a straight alley maze for 1 d (recent), 20 d of continuous training (continuous), or testing 20 d after the original training (remote)
-
State-dependent memory retrieval: insights from neural dynamics and behavioral perspectives Learn. Mem. (IF 2.0) Pub Date : 2023-12-01 Fei Wang, Xu Chen, Binshi Bo, Tianfu Zhang, Kaiyuan Liu, Jun Jiang, Yonggang Wang, Hong Xie, Zhifeng Liang, Ji-Song Guan
Memory retrieval is strikingly susceptible to external states (environment) and internal states (mood states and alcohol), yet we know little about the underlying mechanisms. We examined how internally generated states influence successful memory retrieval using the functional magnetic resonance imaging (fMRI) of laboratory mice during memory retrieval. Mice exhibited a strong tendency to perform memory
-
Serial reversal learning in an olfactory discrimination task in 3xTg-AD mice Learn. Mem. (IF 2.0) Pub Date : 2023-12-01 Kyle M. Roddick, Heather M. Schellinck, Richard E. Brown
Male and female 3xTg-AD mice between 5 and 24 mo of age and their B6129F2/J wild-type controls were tested on a series of 18 olfactory discrimination and reversal tasks in an operant olfactometer. All mice learned the odor discriminations and reversals to a criterion of 85% correct, but the 3xTg-AD mice made fewer errors than the B6129F2/J mice in the odor discriminations and in the first six reversal
-
Parsing memory and nonmemory contributions to age-related declines in mnemonic discrimination performance: a hierarchical Bayesian diffusion decision modeling approach Learn. Mem. (IF 2.0) Pub Date : 2023-11-01 Caroline Chwiesko, John Janecek, Stephanie Doering, Martina Hollearn, Liv McMillan, Joachim Vandekerckhove, Michael D. Lee, Roger Ratcliff, Michael A. Yassa
The mnemonic discrimination task (MDT) is a widely used cognitive assessment tool. Performance in this task is believed to indicate an age-related deficit in episodic memory stemming from a decreased ability to pattern-separate among similar experiences. However, cognitive processes other than memory ability might impact task performance. In this study, we investigated whether nonmnemonic decision-making
-
Cue predictiveness and uncertainty determine cue representation during visual statistical learning Learn. Mem. (IF 2.0) Pub Date : 2023-11-01 Puyuan Zhang, Hui Chen, Shelley Xiuli Tong
This study investigated how humans process probabilistic-associated information when encountering varying levels of uncertainty during implicit visual statistical learning. A novel probabilistic cueing validation paradigm was developed to probe the representation of cues with high (75% probability), medium (50%), low (25%), or zero levels of predictiveness in response to preceding targets that appeared
-
An in vitro analog of learning that food is inedible in Aplysia: decreased responses to a transmitter signaling food after pairing with transmitters signaling failed swallowing Learn. Mem. (IF 2.0) Pub Date : 2023-11-01 Miryam Levy, Jian Jing, Abraham J. Susswein
An in vitro analog of learning that a food is inedible provided insight into mechanisms underlying the learning. Aplysia learn to stop responding to a food when they attempt but fail to swallow it. Pairing a cholinergic agonist with an NO donor or histamine in the Aplysia cerebral ganglion produced significant decreases in fictive feeding in response to the cholinergic agonist alone. Acetylcholine
-
A novel approach to the assessment of higher-order rule learning in male mice Learn. Mem. (IF 2.0) Pub Date : 2023-10-01 Renee Y. Chasse, Peter A. Perrino, Ruth M. McLeod, Gerry T.M. Altmann, R. Holly Fitch
Historically, the development of valid and reliable methods for assessing higher-order cognitive abilities (e.g., rule learning and transfer) has been difficult in rodent models. To date, limited evidence supports the existence of higher cognitive abilities such as rule generation and complex decision-making in mice, rats, and rabbits. To this end, we sought to develop a task that would require mice
-
On the participation of adenosinergic receptors in the reconsolidation of spatial long-term memory in male rats Learn. Mem. (IF 2.0) Pub Date : 2023-10-01 Anne Karine Bosetto Fiebrantz, Luana Felski Leite, Eduarda Dal Pisol Schwab, Juliana Sartori Bonini, Weber Cláudio da Silva
To date, there is insufficient evidence to explain the role of adenosinergic receptors in the reconsolidation of long-term spatial memory. In this work, the role of the adenosinergic receptor family (A1, A2A, A2B, and A3) in this process has been elucidated. It was demonstrated that when infused bilaterally into the hippocampal CA1 region immediately after an early nonreinforced test session performed
-
Presence of a remote fear memory engram in the central amygdala Learn. Mem. (IF 2.0) Pub Date : 2023-10-01 Robert J. Hammack, Victoria E. Fischer, Mary Ann Andrade, Glenn M. Toney
Fear memory formation and recall are highly regulated processes, with the central amygdala (CeA) contributing to fear memory-related behaviors. We recently reported that a remote fear memory engram is resident in the anterior basolateral amygdala (aBLA). However, the extent to which downstream neurons in the CeA participate in this engram is unknown. We tested the hypothesis that CeA neurons activated
-
Better late than never: sleep still supports memory consolidation after prolonged periods of wakefulness Learn. Mem. (IF 2.0) Pub Date : 2023-09-01 Marit Petzka, Ondrej Zika, Bernhard P. Staresina, Scott A. Cairney
While the benefits of sleep for associative memory are well established, it is unclear whether single-item memories profit from overnight consolidation to the same extent. We addressed this question in a preregistered, online study and also investigated how the temporal proximity between learning and sleep influences overnight retention. Sleep relative to wakefulness improved retention of item and
-
Emotional memory consolidation during sleep is associated with slow oscillation–spindle coupling strength in young and older adults Learn. Mem. (IF 2.0) Pub Date : 2023-09-01 Katrina Rodheim, Kyle Kainec, Eunsol Noh, Bethany Jones, Rebecca M.C. Spencer
Emotional memories are processed during sleep; however, the specific mechanisms are unclear. Understanding such mechanisms may provide critical insight into preventing and treating mood disorders. Consolidation of neutral memories is associated with the coupling of NREM sleep slow oscillations (SOs) and sleep spindles (SPs). Whether SO–SP coupling is likewise involved in emotional memory processing
-
Hippocampal memory reactivation during sleep is correlated with specific cortical states of the retrosplenial and prefrontal cortices Learn. Mem. (IF 2.0) Pub Date : 2023-09-01 Pedro A. Feliciano-Ramos, Maria Galazo, Hector Penagos, Matthew Wilson
Episodic memories are thought to be stabilized through the coordination of cortico–hippocampal activity during sleep. However, the timing and mechanism of this coordination remain unknown. To investigate this, we studied the relationship between hippocampal reactivation and slow-wave sleep up and down states of the retrosplenial cortex (RTC) and prefrontal cortex (PFC). We found that hippocampal reactivations
-
Developmental changes in retention and generalization of nonadjacent dependencies over a period containing sleep in 18-mo-old infants Learn. Mem. (IF 2.0) Pub Date : 2023-09-01 Lucia M. Sweeney, Hatty Lara, Rebecca L Gómez
Sleep promotes the stabilization of memories in adulthood, with a growing literature on the benefits of sleep for memory in infants and children. In two studies, we examined the role of sleep in the retention and generalization of nonadjacent dependencies (NADs; e.g., a-X-b/c-X-d phrases) in an artificial language. Previously, a study demonstrated that over a delay of 4 h, 15 mo olds who nap after
-
Sleep-related benefits to transitive inference are modulated by encoding strength and joint rank Learn. Mem. (IF 2.0) Pub Date : 2023-09-01 Tamas Foldes, Lorena Santamaria, Penny Lewis
Transitive inference is a measure of relational learning that has been shown to improve across sleep. Here, we examine this phenomenon further by studying the impact of encoding strength and joint rank. In experiment 1, participants learned adjacent premise pairs and were then tested on inferential problems derived from those pairs. In line with prior work, we found improved transitive inference performance
-
Targeted memory reactivation during slow-wave sleep vs. sleep stage N2: no significant differences in a vocabulary task Learn. Mem. (IF 2.0) Pub Date : 2023-09-01 Anna Wick, Björn Rasch
Sleep supports memory consolidation, and slow-wave sleep (SWS) in particular is assumed to benefit the consolidation of verbal learning material. Re-exposure to previously learned words during SWS with a technique known as targeted memory reactivation (TMR) consistently benefits memory. However, TMR has also been successfully applied during sleep stage N2, though a direct comparison between words selectively
-
The influence of encoding strategy on associative memory consolidation across wake and sleep Learn. Mem. (IF 2.0) Pub Date : 2023-09-01 Dan Denis, Ryan Bottary, Tony J. Cunningham, Mario-Cyriac Tcheukado, Jessica D. Payne
Sleep benefits memory consolidation. However, factors present at initial encoding may moderate this effect. Here, we examined the role that encoding strategy plays in subsequent memory consolidation during sleep. Eighty-nine participants encoded pairs of words using two different strategies. Each participant encoded half of the word pairs using an integrative visualization technique, where the two
-
Sleep consolidates stimulus–response learning Learn. Mem. (IF 2.0) Pub Date : 2023-09-01 Xiu Miao, Carolin Müller, Nicolas D. Lutz, Qing Yang, Florian Waszak, Jan Born, Karsten Rauss
Performing a motor response to a sensory stimulus creates a memory trace whose behavioral correlates are classically investigated in terms of repetition priming effects. Such stimulus–response learning entails two types of associations that are partly independent: (1) an association between the stimulus and the motor response and (2) an association between the stimulus and the classification task in
-
Special issue on sleep and memory Learn. Mem. (IF 2.0) Pub Date : 2023-09-01
The Editors of Learning & Memory are pleased to publish this special issue on sleep and memory. Humans spend roughly one-third of their lives asleep, and it is widely understood that sleep is essential for brain health and cognitive function and is instrumental in the formation and storage of memories. However, much remains to be revealed about specifically how the brain processes memories during sleep
-
A reward effect on memory retention, consolidation, and generalization? Learn. Mem. (IF 2.0) Pub Date : 2023-08-01 Heidrun Schultz, Hanna Stoffregen, Roland G. Benoit
Reward improves memory through both encoding and consolidation processes. In this preregistered study, we tested whether reward effects on memory generalize from high-rewarded items to low-rewarded but episodically related items. Fifty-nine human volunteers incidentally encoded associations between unique objects and repeated scenes. Some scenes typically yielded high reward, whereas others typically
-
Chemogenetic activation of the ventral subiculum–BNST pathway reduces context fear expression Learn. Mem. (IF 2.0) Pub Date : 2023-08-01 Leeza Kopaeva, Alexandrina Yakimov, Louise Urien, Elizabeth P. Bauer
An inability to reduce fear in nonthreatening environments characterizes many anxiety disorders. The pathway from the ventral subiculum (vSUB) to the bed nucleus of the stria terminalis (BNST) is more active in safe contexts than in aversive ones, as indexed by FOS expression. Here, we used chemogenetic techniques to specifically activate the vSUB–BNST pathway during both context and cued fear expression
-
Interpolated retrieval retroactively increases recall and promotes cross-episode memory interdependence Learn. Mem. (IF 2.0) Pub Date : 2023-08-01 Christopher N. Wahlheim, Sydney T. Smith, Sydney M. Garlitch, Robert W. Wiley
Retrieving existing memories before new learning can lead to retroactive facilitation. Three experiments examined whether interpolated retrieval is associated with retroactive facilitation and memory interdependence that reflects integrative encoding. Participants studied two lists of cue–response word pairs that repeated across lists (A–B, A–B), appeared in list 1 (A–B, —), or included the same cues
-
Measuring human context fear conditioning and retention after consolidation Learn. Mem. (IF 2.0) Pub Date : 2023-07-01 Yanfang Xia, Jelena Wehrli, Samuel Gerster, Marijn Kroes, Maxime Houtekamer, Dominik R. Bach
Fear conditioning is a laboratory paradigm commonly used to investigate aversive learning and memory. In context fear conditioning, a configuration of elemental cues (conditioned stimulus [CTX]) predicts an aversive event (unconditioned stimulus [US]). To quantify context fear acquisition in humans, previous work has used startle eyeblink responses (SEBRs), skin conductance responses (SCRs), and verbal
-
Activation of prefrontal cortex and striatal regions in rats after shifting between rules in a T-maze Learn. Mem. (IF 2.0) Pub Date : 2023-07-01 Virginie Oberto, Hongying Gao, Ana Biondi, Susan J. Sara, Sidney I. Wiener
Prefrontal cortical and striatal areas have been identified by inactivation or lesion studies to be required for behavioral flexibility, including selecting and processing of different types of information. In order to identify these networks activated selectively during the acquisition of new reward contingency rules, rats were trained to discriminate orientations of bars presented in pseudorandom
-
Elevated corticosterone after fear learning impairs remote auditory memory retrieval and alters brain network connectivity Learn. Mem. (IF 2.0) Pub Date : 2023-07-01 Niek Brosens, Sylvie L. Lesuis, Ilse Bassie, Lara Reyes, Priya Gajadien, Paul J. Lucassen, Harm J. Krugers
Glucocorticoids are potent memory modulators that can modify behavior in an adaptive or maladaptive manner. Elevated glucocorticoid levels after learning promote memory consolidation at recent time points, but their effects on remote time points are not well established. Here we set out to assess whether corticosterone (CORT) given after learning modifies remote fear memory. To that end, mice were
-
Corrigendum: Depotentiation depends on IP3 receptor activation sustained by synaptic inputs after LTP induction Learn. Mem. (IF 2.0) Pub Date : 2023-05-01 Satoshi Fujii, Yoshihiko Yamazaki, Jun-ichi Goto, Hiroki Fujiwara, Katsuhiko Mikoshiba
Learning & Memory 27: 52–66 (2020)
-
Distribution, cellular localization, and colocalization of several peptide neurotransmitters in the central nervous system of Aplysia Learn. Mem. (IF 2.0) Pub Date : 2023-05-01 Robert D. Hawkins, Lennart Brodin, Elvar Theodorsson, Ákos Végvári, Eric R. Kandel, Tomas Hokfelt
Neuropeptides are widely used as neurotransmitters in vertebrates and invertebrates. In vertebrates, a detailed understanding of their functions as transmitters has been hampered by the complexity of the nervous system. The marine mollusk Aplysia, with a simpler nervous system and many large, identified neurons, presents several advantages for addressing this question and has been used to examine the
-
Pattern separation of fear extinction memory Learn. Mem. (IF 2.0) Pub Date : 2023-05-01 Patrick A.F. Laing, Joseph E. Dunsmoor
While fear generalizes widely, extinction is stimulus-specific. Using a hybrid conditioning/episodic memory paradigm, subjects encoded nonrepeating category exemplars during fear conditioning and extinction. Twenty-four hours later, a surprise memory test included old, similar, and novel category exemplars. Results showed strong dissociation between pattern completion (generalization) and pattern separation
-
Evidence that anterograde learning interference depends on the stage of learning of the interferer: blocked versus interleaved training Learn. Mem. (IF 2.0) Pub Date : 2023-05-01 Ruijing Ning, Beverly A. Wright
Training on one task (task A) can disrupt learning on a subsequently trained task (task B), illustrating anterograde learning interference. We asked whether the induction of anterograde learning interference depends on the learning stage that task A has reached when the training on task B begins. To do so, we drew on previous observations in perceptual learning in which completing all training on one
-
Self-reported encoding quality promotes lure rejections and false alarms Learn. Mem. (IF 2.0) Pub Date : 2023-04-01 Christopher N. Wahlheim, Sydney M. Garlitch, Rawan M. Mohamed, Blaire J. Weidler
The hippocampus supports distinctive encoding, enabling discrimination of perceptions from similar memories. Here, an experimental and individual differences approach examined the role of encoding quality in the classification of similar lures. An object recognition task included thought probes during study and similar lures at test. On-task study reports were associated with lure discrimination in
-
Standardized extract of Ginkgo biloba treatment and novelty on the weak encoding of spatial recognition memory in rats Learn. Mem. (IF 2.0) Pub Date : 2023-04-01 Carla Vitor de Andrade, Andressa Gabriela Soliani, Suzete Maria Cerutti
Long-term memory (LTM) formation is dependent on neurochemical changes that guarantee that a recently formed memory (short-term memory [STM]) remains in the specific neural circuitry via the consolidation process. The persistence of recognition memory has been evidenced by using behavioral tagging in young adult rats, but it has not been effective on aging. Here, we investigated the effects of treatment
-
Specific behaviors during auditory fear conditioning and postsynaptic expression of AMPA receptors in the basolateral amygdala predict interindividual differences in fear generalization in male rats Learn. Mem. (IF 2.0) Pub Date : 2023-04-01 Bruno José Moraes, Oliver Hardt
Auditory fear conditioning in rats is a widely used method to study learning, memory, and emotional responding. Despite procedural standardizations and optimizations, there is substantial interindividual variability in fear expression during test, notably in terms of fear expressed toward the testing context alone. To better understand which factors could explain this variation between subjects, we
-
Neuronal and astrocytic protein degradation are critical for fear memory formation Learn. Mem. (IF 2.0) Pub Date : 2023-03-01 Kayla Farrell, Taylor McFadden, Timothy J. Jarome
Strong evidence has implicated proteasome-mediated protein degradation in the memory consolidation process. However, due to the use of pharmacological approaches, the cell type specificity of this remains unknown. Here, we used neuron-specific and novel astrocyte-specific CRISPR–dCas9–KRAB–MECP2 plasmids to inhibit protein degradation in a cell type-specific manner in the amygdala of male rats. We
-
Sleep disruption by memory cues selectively weakens reactivated memories Learn. Mem. (IF 2.0) Pub Date : 2023-03-01 Nathan W. Whitmore, Ken A. Paller
A widely accepted view in memory research is that recently stored information can be reactivated during sleep, leading to memory strengthening. Two recent studies have shown that this effect can be reversed in participants with highly disrupted sleep. To test whether weakening of reactivated memories can result directly from sleep disruption, in this experiment we varied the intensity of memory reactivation
-
Differential effects of emotional valence on mnemonic performance with greater hippocampal maturity Learn. Mem. (IF 2.0) Pub Date : 2023-03-01 Adam Kimbler, Dana L. McMakin, Nicholas J. Tustison, Aaron T. Mattfeld
The hippocampal formation (HF) facilitates declarative memory, with subfields providing unique contributions to memory performance. Maturational differences across subfields facilitate a shift toward increased memory specificity, with peripuberty sitting at the inflection point. Peripuberty is also a sensitive period in the development of anxiety disorders. We believe HF development during puberty
-
Context matters: changes in memory over a period of sleep are driven by encoding context Learn. Mem. (IF 2.0) Pub Date : 2023-02-01 Eitan Schechtman, Julia Heilberg, Ken A. Paller
During sleep, recently acquired episodic memories (i.e., autobiographical memories for specific events) are strengthened and transformed, a process termed consolidation. These memories are contextual in nature, with details of specific features interwoven with more general properties such as the time and place of the event. In this study, we hypothesized that the context in which a memory is embedded
-
Aging impacts memory for perceptual, but not narrative, event details Learn. Mem. (IF 2.0) Pub Date : 2023-02-01 Angelique I. Delarazan, Charan Ranganath, Zachariah M. Reagh
Memory is well known to decline over the course of healthy aging. However, memory is not a monolith and draws from different kinds of representations. Historically, much of our understanding of age-related memory decline stems from recognition of isolated studied items. In contrast, real-life events are often remembered as narratives, and this kind of information is generally missed in typical recognition
-
Forgetting dynamics for items of different categories Learn. Mem. (IF 2.0) Pub Date : 2023-02-01 Antonios Georgiou, Mikhail Katkov, Misha Tsodyks
How the dynamic evolution of forgetting changes for different material types is unexplored. By using a common experimental paradigm with stimuli of different types, we were able to directly cross-examine the emerging dynamics and found that even though the presentation sets differ minimally by design, the obtained curves appear to fall on a discrete spectrum. We also show that the resulting curves
-
Sleep strengthens resting-state functional communication between brain areas involved in the consolidation of problem-solving skills Learn. Mem. (IF 2.0) Pub Date : 2023-01-01 Nicholas H. van den Berg, Dylan Smith, Zhuo Fang, Alyssa Pozzobon, Balmeet Toor, Julia Al-Kuwatli, Laura Ray, Stuart M. Fogel
Sleep consolidates procedural memory for motor skills, and this process is associated with strengthened functional connectivity in hippocampal–striatal–cortical areas. It is unknown whether similar processes occur for procedural memory that requires cognitive strategies needed for problem-solving. It is also unclear whether a full night of sleep is indeed necessary for consolidation to occur, compared
-
Sleep spindles and slow waves are physiological markers for age-related changes in gray matter in brain regions supporting problem-solving skills Learn. Mem. (IF 2.0) Pub Date : 2023-01-01 Balmeet Toor, Nicholas van den Berg, Laura B. Ray, Stuart M. Fogel
As we age, the added benefit of sleep for memory consolidation is lost. One of the hallmark age-related changes in sleep is the reduction of sleep spindles and slow waves. Gray matter neurodegeneration is related to both age-related changes in sleep and age-related changes in memory, including memory for problem-solving skills. Here, we investigated whether spindles and slow waves might serve as biological
-
Male and female impairments in odor span are observed in a rat model of PTSD Learn. Mem. (IF 2.0) Pub Date : 2023-01-01 Colleen E. McGonigle, Christopher C. Lapish, Marian L. Logrip
Posttraumatic stress disorder (PTSD) is associated with neural and behavioral alterations in response to trauma exposure, including working memory impairments. Rodent models of PTSD have not fully investigated chronic or reactive working memory deficits, despite clinical relevance. The present study uses footshock to induce a posttraumatic stress state in male and female rats and evaluates the effect
-
Discriminating goal-directed and habitual cocaine seeking in rats using a novel outcome devaluation procedure Learn. Mem. (IF 2.0) Pub Date : 2022-12-01 Bradley O. Jones, Adelis M. Cruz, Tabitha H. Kim, Haley F. Spencer, Rachel J. Smith
Habits are theorized to play a key role in compulsive cocaine seeking, yet there is limited methodology for assessing habitual responding for intravenous (IV) cocaine. We developed a novel outcome devaluation procedure to discriminate goal-directed from habitual responding in cocaine-seeking rats. This procedure elicits devaluation temporarily and requires no additional training, allowing repeated
-
Defective synaptic plasticity in a model of Coffin–Lowry syndrome is rescued by simultaneously targeting PKA and MAPK pathways Learn. Mem. (IF 2.0) Pub Date : 2022-12-01 Rong-Yu Liu, Yili Zhang, Paul Smolen, Leonard J. Cleary, John H. Byrne
Empirical and computational methods were combined to examine whether individual or dual-drug treatments can restore the deficit in long-term synaptic facilitation (LTF) of the Aplysia sensorimotor synapse observed in a cellular model of Coffin–Lowry syndrome (CLS). The model was produced by pharmacological inhibition of p90 ribosomal S6 kinase (RSK) activity. In this model, coapplication of an activator
-
Reward does not modulate forgetting in free recall tests Learn. Mem. (IF 2.0) Pub Date : 2022-12-01 Robin Hellerstedt, Deborah Talmi
Reward is thought to attenuate forgetting through the automatic effect of dopamine on hippocampal memory traces. Here we report a conceptual replication of previous results where we did not observe this effect of reward. Participants encoded eight lists of pictures and recalled picture content immediately or the next day. They were informed that they could gain monetary reward for recalling the pictures
-
Reward-motivated memories influence new learning across development Learn. Mem. (IF 2.0) Pub Date : 2022-11-01 Alexandra O. Cohen, Camille V. Phaneuf, Gail M. Rosenbaum, Morgan M. Glover, Kristen N. Avallone, Xinxu Shen, Catherine A. Hartley
Previously rewarding experiences can influence choices in new situations. Past work has demonstrated that existing reward associations can either help or hinder future behaviors and that there is substantial individual variability in the transfer of value across contexts. Developmental changes in reward sensitivity may also modulate the impact of prior reward associations on later goal-directed behavior
-
Decreased associative processing and memory confidence in aphantasia Learn. Mem. (IF 2.0) Pub Date : 2022-11-01 Bianca C. Wittmann, Yılmaz Şatırer
Visual imagery and mental reconstruction of scenes are considered core components of episodic memory retrieval. Individuals with absent visual imagery (aphantasia) score lower on tests of autobiographical memory, suggesting that aphantasia may be associated with differences in episodic and associative processing. In this online study, we tested aphantasic participants and controls on associative recognition
-
Targeted memory reactivation during sleep can induce forgetting of overlapping memories Learn. Mem. (IF 2.0) Pub Date : 2022-11-01 Bárður H. Joensen, Marcus O. Harrington, Sam C. Berens, Scott A. Cairney, M. Gareth Gaskell, Aidan J. Horner
Memory reactivation during sleep can shape new memories into a long-term form. Reactivation of memories can be induced via the delivery of auditory cues during sleep. Although this targeted memory reactivation (TMR) approach can strengthen newly acquired memories, research has tended to focus on single associative memories. It is less clear how TMR affects retention for overlapping associative memories
-
The socially enriched environment test: a new approach to evaluate social behavior in a mouse model of social anxiety disorder Learn. Mem. (IF 2.0) Pub Date : 2022-11-01 Zineb Boudjafad, Asmae Lguensat, Kenza Elmardadi, Asma Dahi, Mohamed Bennis, Saadia Ba-M'hamed, René Garcia
Social anxiety disorder (SAD) is a common anxiety disorder characterized by a marked fear of social situations. Treatments for SAD, including exposure therapy and medication, are not satisfactory for all patients. This has led to the development of several paradigms to study social fear in rodents. However, there are still some social impairments observed in SAD patients that have never been examined
-
Category-specific memory encoding in the medial temporal lobe and beyond: the role of reward Learn. Mem. (IF 2.0) Pub Date : 2022-10-01 Heidrun Schultz, Jungsun Yoo, Dar Meshi, Hauke R. Heekeren
The medial temporal lobe (MTL), including the hippocampus (HC), perirhinal cortex (PRC), and parahippocampal cortex (PHC), is central to memory formation. Reward enhances memory through interplay between the HC and substantia nigra/ventral tegmental area (SNVTA). While the SNVTA also innervates the MTL cortex and amygdala (AMY), their role in reward-enhanced memory is unclear. Prior research suggests
-
The Retrograde Memory for News Events Test (RM-NET) and the relationship between news event memory and performance on standard neuropsychological tests Learn. Mem. (IF 2.0) Pub Date : 2022-10-01 Andrew T.J. Cawley-Bennett, Jennifer C. Frascino, Isabel E. Asp, Shahrokh Golshan, Mark W. Bondi, Zhishang Luo, Christine N. Smith
Novel tests of semantic memory (SM)—for example, memory for news events (NE; news facts) or famous personalities—are useful for estimating the severity of retrograde amnesia. Individuals with mild cognitive impairment exhibit relatively intact SM/language on traditional neuropsychological tests but exhibit consistent impairment on novel tests of SM, suggesting novel SM tests are dissimilar from traditional
-
Enhanced olfactory memory detection in trap-design Y-mazes allows the study of imperceptible memory traces in Drosophila Learn. Mem. (IF 2.0) Pub Date : 2022-10-01 Radhika Mohandasan, Manikrao Thakare, Suhas Sunke, Fathima Mukthar Iqbal, Madhav Sridharan, Gaurav Das
The neural basis of behavior is identified by systematically manipulating the activity of specific neurons and screening for loss or gain of phenotype. Therefore, robust, high-scoring behavioral assays are necessary for determining the neural circuits of novel behaviors. We report a simple Y-maze design for Drosophila olfactory learning and memory assay. Memory scores in our Y-mazes are considerably
-
Higher-order trace conditioning in newborn rabbits Learn. Mem. (IF 2.0) Pub Date : 2022-10-01 Gérard Coureaud, Nina Colombel, Patricia Duchamp-Viret, Guillaume Ferreira
Temporal contingency is a key factor in associative learning but remains weakly investigated early in life. Few data suggest simultaneous presentation is required for young to associate different stimuli, whereas adults can learn them sequentially. Here, we investigated the ability of newborn rabbits to perform sensory preconditioning and second-order conditioning using trace intervals between odor
-
Contributions of sex and genotype to exploratory behavior differences in an aged humanized APOE mouse model of late-onset Alzheimer's disease Learn. Mem. (IF 2.0) Pub Date : 2022-09-01 John W. McLean, Avnish Bhattrai, Francesca Vitali, Adam C. Raikes, Jean-Paul L. Wiegand, Roberta Diaz Brinton
Age, genetics, and chromosomal sex have been identified as critical risk factors for late-onset Alzheimer's disease (LOAD). The predominant genetic risk factor for LOAD is the apolipoprotein E ε4 allele (APOE4), and the prevalence of LOAD is higher in females. However, the translational validity of APOE4 mouse models for AD-related cognitive impairment remains to be fully determined. The present study
-
Spatial anxiety and self-confidence mediate sex/gender differences in mental rotation Learn. Mem. (IF 2.0) Pub Date : 2022-09-01 Linda Arrighi, Markus Hausmann
A recent meta-synthesis study with a sample of >12 million participants revealed that the male advantage in mental rotation (MR) is the largest cognitive sex/gender difference found in psychological literature. MR requires test takers to mentally rotate three-dimensional cubic figures under time restrictions. Previous studies have investigated how biological and social factors contribute to cognitive
-
Sex differences in training-induced activity of the ubiquitin proteasome system in the dorsal hippocampus and medial prefrontal cortex of male and female mice Learn. Mem. (IF 2.0) Pub Date : 2022-09-01 Sarah B. Beamish, Kellie S. Gross, McKenna M. Anderson, Fred J. Helmstetter, Karyn M. Frick
The ubiquitin proteasome system (UPS) is a primary mechanism through which proteins are degraded in cells. UPS activity in the dorsal hippocampus (DH) is necessary for multiple types of memory, including object memory, in male rodents. However, sex differences in DH UPS activation after fear conditioning suggest that other forms of learning may also differentially regulate DH UPS activity in males
-
Sex is predicted by spatial memory multivariate activation patterns Learn. Mem. (IF 2.0) Pub Date : 2022-09-01 Dylan S. Spets, Scott D. Slotnick
Whether sex differences exist in the brain at the macroscopic level, as measured with magnetic resonance imaging (MRI), is a topic of debate. The present spatial long-term memory functional MRI (fMRI) study predicted sex based on event-related patterns of brain activity. Within spatial memory regions of interest, patterns of activity associated with females and males were used to predict the sex of
-
Sex differences in contextual fear learning and generalization: a behavioral and computational analysis of hippocampal functioning Learn. Mem. (IF 2.0) Pub Date : 2022-09-01 Jeremy M. Trott, Franklin B. Krasne, Michael S. Fanselow
There are sex differences in anxiety disorders with regard to occurrence and severity of episodes such that females tend to experience more frequent and more severe episodes. Contextual fear learning and generalization are especially relevant to anxiety disorders, which are often defined by expressing fear and/or anxiety in safe contexts. In contextual fear conditioning, a representation of the context
-
Revisiting sex differences in the acquisition and extinction of threat conditioning in humans Learn. Mem. (IF 2.0) Pub Date : 2022-09-01 Zhenfu Wen, Jamie Fried, Edward F. Pace-Schott, Sara W. Lazar, Mohammed R. Milad
Findings pertaining to sex differences in the acquisition and extinction of threat conditioning, a paradigm widely used to study emotional homeostasis, remain inconsistent, particularly in humans. This inconsistency is likely due to multiple factors, one of which is sample size. Here, we pooled functional magnetic resonance imaging (fMRI) and skin conductance response (SCR) data from multiple studies