journal
MENU ▼
Read by QxMD icon Read
search

Learning & Memory

journal
https://www.readbyqxmd.com/read/27918278/pi3-kinase-cascade-has-a-differential-role-in-acquisition-and-extinction-of-conditioned-fear-memory-in-juvenile-and-adult-rats
#1
Ilana Slouzkey, Mouna Maroun
The basolateral amygdala (BLA), medial prefrontal cortex (mPFC) circuit, plays a crucial role in acquisition and extinction of fear memory. Extinction of aversive memories is mediated, at least in part, by the phosphoinositide-3 kinase (PI3K)/Akt pathway in adult rats. There is recent interest in the neural mechanisms that mediate fear and extinction in juvenile animals and whether these mechanisms are distinctive from those in adult animals. In the present study, we examined (1) changes in phosphorylation of Akt in the BLA and mPFC after fear conditioning and extinction in juvenile and adult rats and (2) the effect of BLA and mPFC localized inhibition of the PI3K following acquisition and extinction of contextual fear memory...
December 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918277/computational-model-of-a-positive-bdnf-feedback-loop-in-hippocampal-neurons-following-inhibitory-avoidance-training
#2
Yili Zhang, Paul Smolen, Cristina M Alberini, Douglas A Baxter, John H Byrne
Inhibitory avoidance (IA) training in rodents initiates a molecular cascade within hippocampal neurons. This cascade contributes to the transition of short- to long-term memory (i.e., consolidation). Here, a differential equation-based model was developed to describe a positive feedback loop within this molecular cascade. The feedback loop begins with an IA-induced release of brain-derived neurotrophic factor (BDNF), which in turn leads to rapid phosphorylation of the cAMP response element-binding protein (pCREB), and a subsequent increase in the level of the β isoform of the CCAAT/enhancer binding protein (C/EBPβ)...
December 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918276/repeated-recall-and-pkm%C3%AE-maintain-fear-memories-in-juvenile-rats
#3
Chicora F Oliver, Patricia Kabitzke, Peter Serrano, Laura J Egan, Gordon A Barr, Harry N Shair, Christoph Wiedenmayer
We examined the neural substrates of fear memory formation and maintenance when repeated recall was used to prevent forgetting in young animals. In contrast to adult rats, juveniles failed to show contextual fear responses at 4 d post-fear conditioning. Reconsolidation sessions 3 and 6 d after conditioning restored contextual fear responses in juveniles 7 d after initial training. In juveniles that received reconsolidation sessions, protein kinase M zeta (PKMζ) increased in the amygdala, but not in the hippocampus...
December 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918275/behavioral-mechanisms-of-context-fear-generalization-in-mice
#4
Kylie A Huckleberry, Laura B Ferguson, Michael R Drew
There is growing interest in generalization of learned contextual fear, driven in part by the hypothesis that mood and anxiety disorders stem from impaired hippocampal mechanisms of fear generalization and discrimination. However, there has been relatively little investigation of the behavioral and procedural mechanisms that might control generalization of contextual fear. We assessed the relative contribution of different contextual features to context fear generalization and characterized how two common conditioning protocols-foreground (uncued) and background (cued) contextual fear conditioning-affected context fear generalization...
December 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918274/stable-long-term-spatial-memory-in-young-and-aged-rats-achieved-with-a-one-day-morris-water-maze-training-protocol
#5
Ruth M Barrientos, Meagan M Kitt, Heather M D'Angelo, Linda R Watkins, Jerry W Rudy, Steven F Maier
Here, we present data demonstrating that a 1 d Morris water maze training protocol is effective at producing stable, long-term spatial memory in both young (3 mo old) and aged (24 mo old) F344xBN rats. Four trials in each of four sessions separated by a 2.5 h ISI produced robust selective search for the platform 1 and 4 d after training, in both age groups. A 1 h ISI protocol did not produce good retention. Also, compressing the trials into just two sessions separated by a 2.5 h ISI produced limited retention in only young rats...
December 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918273/neural-circuits-via-which-single-prolonged-stress-exposure-leads-to-fear-extinction-retention-deficits
#6
Dayan Knox, Briana R Stanfield, Jennifer M Staib, Nina P David, Samantha M Keller, Thomas DePietro
Single prolonged stress (SPS) has been used to examine mechanisms via which stress exposure leads to post-traumatic stress disorder symptoms. SPS induces fear extinction retention deficits, but neural circuits critical for mediating these deficits are unknown. To address this gap, we examined the effect of SPS on neural activity in brain regions critical for extinction retention (i.e., fear extinction circuit). These were the ventral hippocampus (vHipp), dorsal hippocampus (dHipp), basolateral amygdala (BLA), prelimbic cortex (PL), and infralimbic cortex (IL)...
December 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918272/rats-can-acquire-conditional-fear-of-faint-light-leaking-through-the-acrylic-resin-used-to-mount-fiber-optic-cannulas
#7
Adam Eckmier, Willy Daney de Marcillac, Agnès Maître, Thérèse M Jay, Matthew J Sanders, Bill P Godsil
Rodents are exquisitely sensitive to light and optogenetic behavioral experiments routinely introduce light-delivery materials into experimental situations, which raises the possibility that light could leak and influence behavioral performance. We examined whether rats respond to a faint diffusion of light, termed caplight, which emanated through the translucent dental acrylic resin used to affix deep-brain optical cannulas in place. Although rats did not display significant changes in locomotion or rearing to caplight in a darkened open field, they did acquire conditional fear via caplight-footshock pairings...
December 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918271/stress-induced-cortisol-hampers-memory-generalization
#8
Lisa C Dandolo, Lars Schwabe
Integrative encoding and generalization across past experiences depends largely on the hippocampus, an area known to be particularly sensitive to stress. Yet, whether stress influences the ability to generalize memories is unknown. We exposed volunteers to a stressor or a control manipulation before they completed an acquired equivalence task probing memory generalization. While stress left learning performance intact, it reduced participants' ability to generalize and this deficit was directly linked to the cortisol response to the stressor...
December 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918270/interaction-of-inhibitory-and-facilitatory-effects-of-conditioning-trials-on-long-term-memory-formation
#9
Shouhei Hosono, Yukihisa Matsumoto, Makoto Mizunami
Animals learn through experience and consolidate the memories into long-time storage. Conditioning parameters to induce protein synthesis-dependent long-term memory (LTM) have been the subject of extensive studies in many animals. Here we found a case in which a conditioning trial inhibits or facilitates LTM formation depending on the intervals from preceding trials. We studied the effects of conditioning parameters on LTM formation in olfactory conditioning of maxillary-palpi extension response with sucrose reward in the cockroach Periplaneta americana We found, at first, that translation- and transcription-dependent LTM forms 1 h after training, the fastest so far reported in insects...
December 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918288/corrigendum-the-need-for-novel-informatics-tools-for-integrating-and-planning-research-in-molecular-and-cellular-cognition
#10
Alcino J Silva, Klaus-Robert Müller
No abstract text is available yet for this article.
November 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918287/measuring-discrimination-and-reversal-learning-in-mouse-models-within-4-days-and-without-prior-food-deprivation
#11
Esther Remmelink, August B Smit, Matthijs Verhage, Maarten Loos
Many neurological and psychiatric disorders are characterized by deficits in cognitive flexibility. Modeling cognitive flexibility in mice enables the investigation of mechanisms underlying these deficits. The majority of currently available behavioral tests targeting this cognitive domain are reversal learning tasks that require scheduled food restriction, extended training periods and labor-intensive, and stress-inducing animal handling. Here, we describe a novel 4-day (4-d) continuously running task measuring discrimination- and reversal learning in an automated home cage (CognitionWall DL/RL task) that largely eliminates these limitations...
November 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918286/how-does-intentionality-of-encoding-affect-memory-for-episodic-information
#12
Michael Craig, Karla Butterworth, Jonna Nilsson, Colin J Hamilton, Peter Gallagher, Tom V Smulders
Episodic memory enables the detailed and vivid recall of past events, including target and wider contextual information. In this paper, we investigated whether/how encoding intentionality affects the retention of target and contextual episodic information from a novel experience. Healthy adults performed (1) a What-Where-When (WWW) episodic memory task involving the hiding and delayed recall of a number of items (what) in different locations (where) in temporally distinct sessions (when) and (2) unexpected tests probing memory for wider contextual information from the WWW task...
November 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918285/humans-and-monkeys-use-different-strategies-to-solve-the-same-short-term-memory-tasks
#13
John H Wittig, Barak Morgan, Evan Masseau, Barry J Richmond
The neural mechanisms underlying human working memory are often inferred from studies using old-world monkeys. Humans use working memory to selectively memorize important information. We recently reported that monkeys do not seem to use selective memorization under experimental conditions that are common in monkey research, but less common in human research. Here we compare the performance of humans and monkeys under the same experimental conditions. Humans selectively remember important images whereas monkeys largely rely on recency information from nonselective memorization...
November 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918284/context-specificity-of-both-acquisition-and-extinction-of-a-pavlovian-conditioned-response
#14
Sarah Starosta, Metin Uengoer, Isabelle Bartetzko, Sara Lucke, Onur Güntürkün, Maik C Stüttgen
It is widely held that the extinction of a conditioned response is more context specific than its initial acquisition. One proposed explanation is that context serves to disambiguate the meaning of a stimulus. Using a procedure that equated the learning histories of the contexts, we show that the memory of an appetitive Pavlovian association can be highly context specific despite being unambiguous. This result is inconsistent with predictions of the Rescorla-Wagner model of learning but in line with configural accounts of contextual control of behavior...
November 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918283/muscarinic-acetylcholine-receptors-act-in-synergy-to-facilitate-learning-and-memory
#15
Katherine Leaderbrand, Helen J Chen, Kevin A Corcoran, Anita L Guedea, Vladimir Jovasevic, Jurgen Wess, Jelena Radulovic
Understanding how episodic memories are formed and retrieved is necessary if we are to treat disorders in which they malfunction. Muscarinic acetylcholine receptors (mAChR) in the hippocampus and cortex underlie memory formation, but there is conflicting evidence regarding their role in memory retrieval. Additionally, there is no consensus on which mAChR subtypes are critical for memory processing. Using pharmacological and genetic approaches, we found that (1) encoding and retrieval of contextual memory requires mAChR in the dorsal hippocampus (DH) and retrosplenial cortex (RSC), (2) memory formation requires hippocampal M3 and cooperative activity of RSC M1 and M3, and (3) memory retrieval is more impaired by inactivation of multiple M1-M4 mAChR in DH or RSC than inactivation of individual receptor subtypes...
November 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918282/conditioned-object-preference-an-alternative-approach-to-measuring-reward-learning-in-rats
#16
Bruce C Kennedy, Maulika Kohli, Jamie J Maertens, Paulina S Marell, Jonathan C Gewirtz
Pavlovian conditioned approach behavior can be directed as much toward discrete cues as it is toward the environmental contexts in which those cues are encountered. The current experiments characterized a tendency of rats to approach object cues whose prior exposure had been paired with reward (conditioned object preference, COP). To demonstrate the phenomenon, rats were conditioned to associate cocaine or saline with two different objects. Rats acquired a preference, assessed using investigation times directed toward each object, for the cocaine-paired object following conditioning...
November 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918281/subsecond-fear-discrimination-in-rats-adult-impairment-in-adolescent-heavy-alcohol-drinkers
#17
Alyssa DiLeo, Kristina M Wright, Michael A McDannald
Discriminating safety from danger must be accurate and rapid. Yet, the rapidity with which fear discrimination emerges remains unknown. Rapid fear discrimination in adulthood may be susceptible to impairment by adolescent heavy alcohol drinking, which increases incidence of anxiety disorders. Rats were given voluntary, adolescent alcohol access, and heavy drinkers were identified. In adulthood, rapid fear discrimination of safety, uncertainty, and danger cues was assessed. Normal rats, but not heavy drinkers, showed discriminative fear <1 sec following cue onset...
November 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918280/lateral-not-medial-prefrontal-cortex-contributes-to-punishment-and-aversive-instrumental-learning
#18
Philip Jean-Richard-Dit-Bressel, Gavan P McNally
Aversive outcomes punish behaviors that cause their occurrence. The prefrontal cortex (PFC) has been implicated in punishment learning and behavior, although the exact roles for different PFC regions in instrumental aversive learning and decision-making remain poorly understood. Here, we assessed the role of the orbitofrontal (OFC), rostral agranular insular (RAIC), prelimbic (PL), and infralimbic (IL) cortex in instrumental aversive learning and decision-making. Rats that pressed two individually presented levers for pellet rewards rapidly suppressed responding to one lever if it also caused mild punishment (punished lever) but continued pressing the other lever that did not cause punishment (unpunished lever)...
November 2016: Learning & Memory
https://www.readbyqxmd.com/read/27918279/the-sensory-features-of-a-food-cue-influence-its-ability-to-act-as-an-incentive-stimulus-and-evoke-dopamine-release-in-the-nucleus-accumbens-core
#19
Bryan F Singer, Myranda A Bryan, Pavlo Popov, Raymond Scarff, Cody Carter, Erin Wright, Brandon J Aragona, Terry E Robinson
The sensory properties of a reward-paired cue (a conditioned stimulus; CS) may impact the motivational value attributed to the cue, and in turn influence the form of the conditioned response (CR) that develops. A cue with multiple sensory qualities, such as a moving lever-CS, may activate numerous neural pathways that process auditory and visual information, resulting in CRs that vary both within and between individuals. For example, CRs include approach to the lever-CS itself (rats that "sign-track"; ST), approach to the location of reward delivery (rats that "goal-track"; GT), or an "intermediate" combination of these behaviors...
November 2016: Learning & Memory
https://www.readbyqxmd.com/read/27634149/dna-methylation-a-permissive-mark-in-memory-formation-and-maintenance
#20
Ana M M Oliveira
DNA methylation was traditionally viewed as a static mechanism required during cell fate determination. This view has been challenged and it is now accepted that DNA methylation is involved in the regulation of genomic responses in mature neurons, particularly in cognitive functions. The evidence for a role of DNA methylation in memory formation and maintenance comes from the increasing number of studies that have assessed the effects of manipulation of DNA methylation modifiers in the ability to form and maintain memories...
October 2016: Learning & Memory
journal
journal
32021
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"