Hippocampal and amygdala volumes vary with residential proximity to toxicants at Birmingham, Alabama’s 35th Avenue Superfund site.
Behavioral Neuroscience, Vol 137(5), Oct 2023, 330-338; doi:10.1037/bne0000564Exposure to environmental toxicants have serious implications for the general health and well-being of children, particularly during pivotal neurodevelopmental stages. The Environmental Protection Agency’s (EPA) Superfund program has identified several areas (Superfund sites) across the United States with high levels of environmental toxicants, which affect the health of many residents in nearby communities. Exposure to these environmental toxicants has been linked to changes in the structure and function of the brain. However, limited research...
Source: Behavioral Neuroscience - July 20, 2023 Category: Neuroscience Source Type: research

Mental representations mediate aversive learning in humans.
Behavioral Neuroscience, Vol 137(5), Oct 2023, 319-329; doi:10.1037/bne0000565Mental representations of stimuli that are not physically present are critical for a range of cognitive capacities, including perception, memory, and learning. Overly robust mental representations, however, can contribute to hallucinations in healthy individuals and those diagnosed with psychotic illness. Measuring the strength of mental representations can thus provide insight into how the contents of the mind influence both adaptive and maladaptive behaviors. In rodents, the robustness of mental representations has been tested using the represe...
Source: Behavioral Neuroscience - July 6, 2023 Category: Neuroscience Source Type: research

Proteome analysis indicates participation of the dorsal hippocampal formation in fear-motivated memory in a time-dependent manner.
Behavioral Neuroscience, Vol 137(5), Oct 2023, 303-318; doi:10.1037/bne0000563Our previous behavioral and molecular data indicate a central role of the dorsal hippocampal formation (dHF) in recent conditioned lick suppression memory. The purpose of this study was to investigate the role of the dHF in recent and remote memory of conditioned lick suppression employing proteomic analysis. Two or 40 days after conditioning, the rats were subjected to a retention test and were then euthanized after 24 hr for dHF collection. We identified 1,165 proteins and quantified 265 proteins. Upregulation of five proteins and downregulatio...
Source: Behavioral Neuroscience - July 6, 2023 Category: Neuroscience Source Type: research

Distinct competitive impacts of palatability of taste stimuli on sampling dynamics during a preference test.
Behavioral Neuroscience, Vol 137(5), Oct 2023, 289-302; doi:10.1037/bne0000562Food or taste preference tests are analogous to naturalistic decisions in which the animal selects which stimuli to sample and for how long to sample them. The data acquired in such tests, the relative amounts of the alternative stimuli that are sampled and consumed, indicate the preference for each. While such preferences are typically recorded as a single quantity, an analysis of the ongoing sampling dynamics producing the preference can reveal otherwise hidden aspects of the decision-making process that depend on its underlying neural circuit ...
Source: Behavioral Neuroscience - June 29, 2023 Category: Neuroscience Source Type: research

Muscimol inactivation of dorsal striatum in young and aged male rats does not affect paired associates learning performance.
This study found that inactivation of the DS did not alter PAL performance in young or aged rats, but did alter a positive control, DS-dependent spatial navigation task. This observation suggests that elevated DS activity does not play a role in the decline of HPC-dependent PAL performance in aged male rats. Given the persistent tendencies of aged rodents toward DS-dependent learning, it will be worthwhile to explore further the coordination dynamics between the HPC and DS that may contribute to age-related cognitive decline. (PsycInfo Database Record (c) 2023 APA, all rights reserved) (Source: Behavioral Neuroscience)
Source: Behavioral Neuroscience - June 15, 2023 Category: Neuroscience Source Type: research

A single dose of ketamine enhances early life stress-induced aggression with no effect on fear memory, anxiety-like behavior, or depression-like behavior in mice.
Behavioral Neuroscience, Vol 137(5), Oct 2023, 281-288; doi:10.1037/bne0000560Ketamine is a dissociative anesthetic that has been shown to have antidepressant effects in humans and has been proposed as a potential treatment for mood disorders such as posttraumatic stress disorder and aggression. However, previous studies from our lab and others have demonstrated that ketamine’s effects are highly context- and dose-dependent. In a recent study, we found that 10 mg/kg ketamine could exacerbate the effects of early life stress on excessive aggression in mice. To further investigate, the effect of ketamine on moods, such as ...
Source: Behavioral Neuroscience - June 15, 2023 Category: Neuroscience Source Type: research

The motivational role of the ventral striatum and amygdala in learning from gains and losses.
Behavioral Neuroscience, Vol 137(4), Aug 2023, 268-280; doi:10.1037/bne0000558The ventral striatum (VS) and amygdala are two structures often implicated as essential structures for learning. The literature addressing the contribution of these areas to learning, however, is not entirely consistent. We propose that these inconsistencies are due to learning environments and the effect they have on motivation. To differentiate aspects of learning from environmental factors that affect motivation, we ran a series of experiments with varying task factors. We compared monkeys (Macaca mulatta) with VS lesions, amygdala lesions, an...
Source: Behavioral Neuroscience - May 4, 2023 Category: Neuroscience Source Type: research

Ketamine facilitates appetitive trace conditioning in mice: Further evidence for abnormal stimulus representation in schizophrenia model animals.
Behavioral Neuroscience, Vol 137(4), Aug 2023, 236-253; doi:10.1037/bne0000559Recent studies indicated that positive symptoms of schizophrenia, such as hallucination and delusion, can be modeled using Pavlovian conditioning procedures. Various schizophrenia model animals exhibit abnormally strong associative activations of absent stimuli (i.e., conditioned hallucination) and readily form further associations involving the absent cues (i.e., enhanced mediated conditioning). In the present study using mice, we examined whether the acquisition of appetitive trace conditioning, another Pavlovian task in which animals must form...
Source: Behavioral Neuroscience - May 1, 2023 Category: Neuroscience Source Type: research

Divergent risky decision-making and impulsivity behaviors in Lewis rat substrains with low genetic difference.
In conclusion, Lewis rat substrains differ significantly in risk-taking and impulsivity and only a small number of easily mapped variants are likely to be causal. Sequencing combined with a reduced complexity cross should enable identification of one or more variants underlying multiple complex addiction-relevant behaviors. (PsycInfo Database Record (c) 2023 APA, all rights reserved) (Source: Behavioral Neuroscience)
Source: Behavioral Neuroscience - April 27, 2023 Category: Neuroscience Source Type: research

Prefrontal and medial temporal interactions in memory functions in the rhesus monkey.
Behavioral Neuroscience, Vol 137(3), Jun 2023, 211-222; doi:10.1037/bne0000556Both the medial temporal lobe and the dorsolateral prefrontal cortex have been implicated in learning and memory. However, it has been difficult to ascertain the degree to which the two structures are dependent on each other or interact in subserving these cognitive functions. To investigate this question directly, we prepared two group of monkeys. First, the contralateral frontal-hippocampal split group (CFHS) received a unilateral lesion of the hippocampus and surrounding posterior parahippocampal cortices (H +), combined with a contralateral l...
Source: Behavioral Neuroscience - April 6, 2023 Category: Neuroscience Source Type: research

The medial preoptic area and its projections to the ventral tegmental area and the periaqueductal gray are activated in response to social play behavior in juvenile rats.
Behavioral Neuroscience, Vol 137(4), Aug 2023, 223-235; doi:10.1037/bne0000555The medial preoptic area (MPOA) is well known for its role in sexual and maternal behaviors. This region also plays an important role in affiliative social behaviors outside reproductive contexts. We recently demonstrated that the MPOA is a central nucleus in which opioids govern highly rewarding social play behavior in adolescent rats. However, the neural circuit mechanisms underlying MPOA-mediated social play remain largely unresolved. We hypothesized that the MPOA unites a complementary neural system through which social play induces reward vi...
Source: Behavioral Neuroscience - March 6, 2023 Category: Neuroscience Source Type: research

Maternal repetitive hypoxia prior to mating confers epigenetic resilience to memory impairment in male progeny.
Behavioral Neuroscience, Vol 137(3), Jun 2023, 178-183; doi:10.1037/bne0000554We showed previously in a mouse model of vascular cognitive impairment and dementia involving chronic cerebral hypoperfusion (CCH) that repetitive hypoxic conditioning (RHC) of both parents results in the epigenetic, intergenerational transmission of resilience to recognition memory loss in adult progeny, as assessed by the novel object recognition test. The present study was undertaken in the same model to determine whether RHC treatment of one or both parents is required to confer dementia resilience intergenerationally. We found inherited resi...
Source: Behavioral Neuroscience - March 2, 2023 Category: Neuroscience Source Type: research

Examination of onset trajectories and persistence of binge-like eating behavior in mice after intermittent palatable food exposure.
Behavioral Neuroscience, Vol 137(3), Jun 2023, 170-177; doi:10.1037/bne0000550Binge eating is a persistent behavior associated with a chronic course of illness and poor treatment outcomes. While clinical research is unable to capture the full course of binge eating, preclinical approaches offer the opportunity to examine binge-like eating from onset through chronic durations, allowing identification of factors contributing to binge eating persistence. The present study quantified the trajectories of binge-like eating onset and modeled cycles of abstinence/relapse to develop a translational model for binge eating persistenc...
Source: Behavioral Neuroscience - February 23, 2023 Category: Neuroscience Source Type: research

Biological sex influences the contribution of sign-tracking and anxiety-like behavior toward remifentanil self-administration.
Behavioral Neuroscience, Vol 137(3), Jun 2023, 196-210; doi:10.1037/bne0000551Most people sample addictive drugs, but use becomes disordered in only a small minority. Two important factors that influence susceptibility to addiction are individual differences in personality traits and biological sex. The influence of traits on addiction-like behavior is well-characterized in preclinical models of cocaine self-administration, but less is understood in regards to opioids. How biological sex influences trait susceptibility to opioid self-administration is likewise less studied than psychostimulants. Thus, we sought to elucidat...
Source: Behavioral Neuroscience - February 13, 2023 Category: Neuroscience Source Type: research

The role of the anterior cingulate cortex in aggression and impulsivity.
Behavioral Neuroscience, Vol 137(3), Jun 2023, 155-169; doi:10.1037/bne0000552Aggression is a complex social behavior that evolved in the context of defending a territory, fighting for limited resources, and competing for mates and protection. Although aggression considered as a negative or undesirable emotion is an essential part of many species’ repertoire of social behaviors. For humans, the motivations, actions, and limits of aggressive acts are not always clear. However, uncontrolled aggression may have destructive consequences, and it develops inappropriately into violence. At the neural level, several studies demo...
Source: Behavioral Neuroscience - February 9, 2023 Category: Neuroscience Source Type: research