The dopamine system has been implicated in decision-making particularly when associated with effortful behavior. We examined acute optogenetic stimulation of dopamine cells in the ventral tegmental area (VTA) as mice engaged in an effort-based decision-making task. Tyrosine hydroxylase-Cre mice were injected with Cre-dependent ChR2 or eYFP control…

Strong evidence supports a role for protein degradation in fear memory formation. However, these data have been largely done in only male animals. Here, we found that following contextual fear conditioning, females, but not males, had increased levels of proteasome activity and K48 polyubiquitin protein targeting in the dorsal hippocampus, the…

Early life stress (ELS) experiences can cause changes in cognitive and affective functioning. This study examined the persistent effects of a single traumatic event in infancy on several adult behavioral outcomes in male and female C57BL/6J mice. Mice received 15 footshocks in infancy and were tested for stress-enhanced fear learning, extinction…

In two instrumental conditioning experiments with rats, we examined the impacts of acquisition and extinction cues on ABC renewal of instrumental behavior. Animals were reinforced with food for lever pressing in one context, followed by extinction of the response in a second one. Presentations of a brief tone accompanied extinction in Experiment 1…

Conditioned stimuli (CS) have multiple psychological functions that can potentially contribute to their effect on memory formation. It is generally believed that CS-induced memory modulation is primarily due to conditioned emotional responses, however, well-learned CSs not only generate the appropriate behavioral and physiological reactions…

In hippocampal CA1 neurons of wild-type mice, a short tetanus (15 or 20 pulses at 100 Hz) or a standard tetanus (100 pulses at 100 Hz) to a naive input pathway induces long-term potentiation (LTP) of the responses. Low-frequency stimulation (LFS; 1000 pulses at 1 Hz) 60 min after the standard tetanus reverses LTP (depotentiation [DP]), while LFS…

Neural network dynamics underlying flexible animal behaviors remain elusive. The fruit fly "Drosophila" melanogaster is considered an excellent model in behavioral neuroscience because of its simple neuroanatomical architecture and the availability of various genetic methods. Moreover, "Drosophila" larvae's transparent body…

Protein kinase M[zeta] (PKM[zeta]) maintains long-term potentiation (LTP) and long-term memory through persistent increases in kinase expression. Early-life adversity is a precursor to adult mood and anxiety disorders, in part, through persistent disruption of emotional memory throughout life. Here we subjected 10- to 16-wk-old male bonnet…

Behavioral flexibility is important in a changing environment. Previous research suggests that systems consolidation, a long-term poststorage process that alters memory traces, may reduce behavioral flexibility. However, exactly how systems consolidation affects flexibility is unknown. Here, we tested how systems consolidation affects: (1)…

Motivationally attractive cues can draw in behavior in a phenomenon termed incentive salience. Incentive cue attraction is an important model for animal models of drug seeking and relapse. One question of interest is the extent to which the pursuit of motivationally attractive cues is related to the value of the paired outcome or can become…

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…

Pavlovian fear conditioning is a widely used behavioral paradigm for studying associative learning in rodents. Despite early recognition that subjects may engage in a variety of both conditioned and unconditioned responses, the last several decades have seen the field narrow its focus to measure freezing as the sole indicator of conditioned fear.…

Balancing exploration and anti-predation are fundamental to the fitness and survival of all animal species from early life stages. How these basic survival instincts drive learning remains poorly understood. Here, using a light/dark preference paradigm with well-controlled luminance history and constant visual surrounding in larval zebrafish, we…

This paper examines recent evidence from behavioral and neuroscience research with nonhuman animals that suggests the intriguing possibility that they, like their human counterparts, are vulnerable to creating false memories. Once considered a uniquely human memory phenomenon, the creation of false memories in lower animals can be seen especially…

Working memory (WM), the capacity for short-term storage of small quantities of information for immediate use, is thought to depend on activity within the prefrontal cortex. Recent evidence indicates that the prefrontal neuronal activity supporting WM is driven by thalamocortical connections arising in mediodorsal thalamus (mdThal). However, the…