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Cell Jan 2023The hypothalamus regulates innate social behaviors, including mating and aggression. These behaviors can be evoked by optogenetic stimulation of specific neuronal...
The hypothalamus regulates innate social behaviors, including mating and aggression. These behaviors can be evoked by optogenetic stimulation of specific neuronal subpopulations within MPOA and VMHvl, respectively. Here, we perform dynamical systems modeling of population neuronal activity in these nuclei during social behaviors. In VMHvl, unsupervised analysis identified a dominant dimension of neural activity with a large time constant (>50 s), generating an approximate line attractor in neural state space. Progression of the neural trajectory along this attractor was correlated with an escalation of agonistic behavior, suggesting that it may encode a scalable state of aggressiveness. Consistent with this, individual differences in the magnitude of the integration dimension time constant were strongly correlated with differences in aggressiveness. In contrast, approximate line attractors were not observed in MPOA during mating; instead, neurons with fast dynamics were tuned to specific actions. Thus, different hypothalamic nuclei employ distinct neural population codes to represent similar social behaviors.
Topics: Animals; Sexual Behavior, Animal; Ventromedial Hypothalamic Nucleus; Hypothalamus; Aggression; Social Behavior
PubMed: 36608653
DOI: 10.1016/j.cell.2022.11.027 -
Journal of Child and Adolescent... Oct 2019Aggressive behavior is among the most common reasons for referral to psychiatric clinics and confers significant burden on individuals. Aggression remains poorly... (Review)
Review
Aggressive behavior is among the most common reasons for referral to psychiatric clinics and confers significant burden on individuals. Aggression remains poorly defined; there is currently no consensus on the best ways to recognize, diagnose, and treat aggression in clinical settings. In this review, we synthesize the available literature on aggression in children and adolescents and propose the concept of impulsive aggression (IA) as an important construct associated with diverse and enduring psychopathology. Articles were identified and screened from online repositories, including PubMed, PsychInfo, the Cochrane Database, EMBase, and relevant book chapters, using combinations of search terms such as "aggression," "aggressive behavio(u)r," "maladaptive aggression," "juvenile," and "developmental trajectory." These were evaluated for quality of research before being incorporated into the article. The final report references 142 sources, published from 1987 to 2019. Aggression can be either adaptive or maladaptive in nature, and the latter may require psychosocial and biomedical interventions when it occurs in the context of central nervous system psychopathology. Aggression can be categorized into various subtypes, including reactive/proactive, overt/covert, relational, and IA. IA in psychiatric or neurological disorders is reviewed along with current treatments, and an algorithm for systematic evaluation of aggression in the clinical setting is proposed. IA is a treatable form of maladaptive aggression that is distinct from other aggression subtypes. It occurs across diverse psychiatric and neurological diagnoses and affects a substantial subpopulation. IA can serve as an important construct in clinical practice and has considerable potential to advance research.
Topics: Adolescent; Aggression; Child; Humans; Impulsive Behavior; Mental Disorders
PubMed: 31453715
DOI: 10.1089/cap.2019.0039 -
CNS Spectrums Jun 2015Elevations of impulsive behavior have been observed in a number of serious mental illnesses. These phenomena can lead to harmful behaviors, including violence, and thus... (Review)
Review
Elevations of impulsive behavior have been observed in a number of serious mental illnesses. These phenomena can lead to harmful behaviors, including violence, and thus represent a serious public health concern. Such violence is often a reason for psychiatric hospitalization, and it often leads to prolonged hospital stays, suffering by patients and their victims, and increased stigmatization. Despite the attention paid to violence, little is understood about its neural basis in schizophrenia. On a psychological level, aggression in schizophrenia has been primarily attributed to psychotic symptoms, desires for instrumental gain, or impulsive responses to perceived personal slights. Often, multiple attributions can coexist during a single aggressive incident. In this review, I discuss the neural circuitry associated with impulsivity and aggression in schizophrenia, with an emphasis on implications for treatment. Impulsivity appears to account for a great deal of aggression in schizophrenia, especially in inpatient settings. Urgency, defined as impulsivity in the context of strong emotion, is the primary focus of this article. It is elevated in several psychiatric disorders, and in schizophrenia, it has been related to aggression. Many studies have implicated dysfunctional frontotemporal circuitry in impulsivity and aggression in schizophrenia, and pharmacological treatments may act via that circuitry to reduce urgency and aggressive behaviors; however, more mechanistic studies are critically needed. Recent studies point toward manipulable neurobehavioral targets and suggest that cognitive, pharmacological, neuromodulatory, and neurofeedback treatment approaches can be developed to ameliorate urgency and aggression in schizophrenia. It is hoped that these approaches will improve treatment efficacy.
Topics: Aggression; Humans; Impulsive Behavior; Nerve Net; Neurobiology; Schizophrenic Psychology
PubMed: 25900066
DOI: 10.1017/S1092852915000206 -
Tijdschrift Voor Psychiatrie 2019To provide an overview of the literature on transitions towards smoke-free psychiatric hospitals and the risk of aggression.
METHOD: A systematic search was made in...To provide an overview of the literature on transitions towards smoke-free psychiatric hospitals and the risk of aggression.
METHOD: A systematic search was made in medline, Embase and Psycinfo. Studies were included if they reported data on: a smoke-free intervention in a psychiatric hospital or ward, the number of aggressive incidents, and seclusions or prn drugs.
RESULTS: A total of 17 studies matched the inclusion/exclusion criteria; 5 reported a decrease in the number of aggressive incidents after implementation of a smoke-free ward, 7 showed an increase in the number of incidents, and 5 studies reported no differences. Heterogeneity between the studies was high with respect to the definition and implementation of the intervention, the definition and measurement of aggression, study design, length of follow-up, and the sample size.
CONCLUSION: These findings suggest that, after changing the policy towards a smoke-free psychiatric hospital, the risk of aggression is limited. However, several precautions related to the preparation and implementation of this transition seem to be essential. The results support further investment in the implementation of smoke-free psychiatric hospitals in the Netherlands, while maintaining safety.Topics: Aggression; Hospitals, Psychiatric; Humans; Netherlands; Smoke-Free Policy; Smoking Cessation; Violence
PubMed: 31243749
DOI: No ID Found -
Pharmacological Reviews Jul 2016Antiepileptic drugs (AEDs) have many benefits but also many side effects, including aggression, agitation, and irritability, in some patients with epilepsy. This article... (Review)
Review
Antiepileptic drugs (AEDs) have many benefits but also many side effects, including aggression, agitation, and irritability, in some patients with epilepsy. This article offers a comprehensive summary of current understanding of aggressive behaviors in patients with epilepsy, including an evidence-based review of aggression during AED treatment. Aggression is seen in a minority of people with epilepsy. It is rarely seizure related but is interictal, sometimes occurring as part of complex psychiatric and behavioral comorbidities, and it is sometimes associated with AED treatment. We review the common neurotransmitter systems and brain regions implicated in both epilepsy and aggression, including the GABA, glutamate, serotonin, dopamine, and noradrenaline systems and the hippocampus, amygdala, prefrontal cortex, anterior cingulate cortex, and temporal lobes. Few controlled clinical studies have used behavioral measures to specifically examine aggression with AEDs, and most evidence comes from adverse event reporting from clinical and observational studies. A systematic approach was used to identify relevant publications, and we present a comprehensive, evidence-based summary of available data surrounding aggression-related behaviors with each of the currently available AEDs in both adults and in children/adolescents with epilepsy. A psychiatric history and history of a propensity toward aggression/anger should routinely be sought from patients, family members, and carers; its presence does not preclude the use of any specific AEDs, but those most likely to be implicated in these behaviors should be used with caution in such cases.
Topics: Aggression; Anticonvulsants; Brain; Epilepsy; Humans; Neurotransmitter Agents
PubMed: 27255267
DOI: 10.1124/pr.115.012021 -
Social Neuroscience Aug 2022Aggression occurs frequently and severely between rival groups. Although there has been much study into the psychological and socio-ecological determinants of intergroup...
Aggression occurs frequently and severely between rival groups. Although there has been much study into the psychological and socio-ecological determinants of intergroup aggression, the neuroscience of this phenomenon remains incomplete. To examine the neural correlates of aggression directed at outgroup (versus ingroup) targets, we recruited 35 healthy young male participants who were current or former students of the same university. While undergoing functional MRI, participants completed an aggression task against both an ingroup and an outgroup opponent in which their opponents repeatedly provoked them at varying levels and then participants could retaliate. Participants were then socially included and then excluded by two outgroup members and then completed the same aggression task against the same two opponents. Both before and after outgroup exclusion, aggression toward outgroup members was positively associated with activity in the ventral striatum during decisions about how aggressive to be toward their outgroup opponent. Aggression toward outgroup members was also linked to greater post-exclusion activity in the rostral and dorsal medial prefrontal cortex during provocation from their outgroup opponent. These altered patterns of brain activity suggest that frontostriatal mechanisms may play a significant role in motivating aggression toward outgroup members.
Topics: Aggression; Humans; Magnetic Resonance Imaging; Male; Prefrontal Cortex; Ventral Striatum
PubMed: 35658812
DOI: 10.1080/17470919.2022.2086617 -
Pharmacology, Biochemistry, and Behavior Nov 2017Inter-male aggression is an essential component of social behavior in organisms from insects to humans. However, when expressed inappropriately, aggression poses... (Review)
Review
Inter-male aggression is an essential component of social behavior in organisms from insects to humans. However, when expressed inappropriately, aggression poses significant threats to the mental and physical health of both the aggressor and the target. Inappropriate aggression is a common feature of numerous neuropsychiatric disorders in humans and has been hypothesized to result from the atypical activation of reward circuitry in response to social targets. The lateral habenula (LHb) has recently been identified as a major node of the classical reward circuitry and inhibits the release of dopamine from the midbrain to signal negative valence. Here, we discuss the evidence linking LHb function to aggression and its valence, arguing that strong LHb outputs to the ventral tegmental area (VTA) and the dorsal raphe nucleus (DRN) are likely to play roles in aggression and its rewarding components. Future studies should aim to elucidate how various inputs and outputs of the LHb shape motivation and reward in the context of aggression.
Topics: Aggression; Animals; Dopamine; Habenula; Humans; Nerve Net; Neural Pathways; Social Behavior
PubMed: 28499809
DOI: 10.1016/j.pbb.2017.05.003 -
Journal of Child and Adolescent... Feb 2016This selective review provides a model of the neurobiology of impulsive aggression from a cognitive neuroscience perspective. It is argued that prototypical cases of... (Review)
Review
This selective review provides a model of the neurobiology of impulsive aggression from a cognitive neuroscience perspective. It is argued that prototypical cases of impulsive aggression, those associated with anger, involve the recruitment of the acute threat response system structures; that is, the amygdala, hypothalamus, and periaqueductal gray. It is argued that whether the recruitment of these structures results in impulsive aggression or not reflects the functional roles of ventromedial frontal cortex and dorsomedial frontal and anterior insula cortex in response selection. It is also argued that impulsive aggression may occur because of impaired decision making. The aggression may not be accompanied by anger, but it will reflect disrupted evaluation of the rewards/benefits of the action.
Topics: Aggression; Brain; Humans; Impulsive Behavior; Neurobiology
PubMed: 26465707
DOI: 10.1089/cap.2015.0088 -
BMC Biology May 2022Aggression is an adaptive behaviour that animals use to protect offspring, defend themselves and obtain resources. Zebrafish, like many other animals, are not able to...
BACKGROUND
Aggression is an adaptive behaviour that animals use to protect offspring, defend themselves and obtain resources. Zebrafish, like many other animals, are not able to recognize themselves in the mirror and typically respond to their own reflection with aggression. However, mirror aggression is not an all-or-nothing phenomenon, with some individuals displaying high levels of aggression against their mirror image, while others show none at all. In the current work, we have investigated the genetic basis of mirror aggression by using a classic forward genetics approach - selective breeding for high and low mirror aggression zebrafish (HAZ and LAZ).
RESULTS
We characterized AB wild-type zebrafish for their response to the mirror image. Both aggressive and non-aggressive fish were inbred over several generations. We found that HAZ were on average more aggressive than the corresponding LAZ across generations and that the most aggressive adult HAZ were less anxious than the least aggressive adult LAZ after prolonged selective breeding. RNAseq analysis of these fish revealed that hundreds of protein-encoding genes with important diverse biological functions such as arsenic metabolism (as3mt), cell migration (arl4ab), immune system activity (ptgr1), actin cytoskeletal remodelling (wdr1), corticogenesis (dgcr2), protein dephosphorylation (ublcp1), sialic acid metabolism (st6galnac3) and ketone body metabolism (aacs) were differentially expressed between HAZ and LAZ, suggesting a strong genetic contribution to this phenotype. DAVID pathway analysis showed that a number of diverse pathways are enriched in HAZ over LAZ including pathways related to immune function, oxidation-reduction processes and cell signalling. In addition, weighted gene co-expression network analysis (WGCNA) identified 12 modules of highly correlated genes that were significantly associated with aggression duration and/or experimental group.
CONCLUSIONS
The current study shows that selective breeding based of the mirror aggression phenotype induces strong, heritable changes in behaviour and gene expression within the brain of zebrafish suggesting a strong genetic basis for this behaviour. Our transcriptomic analysis of fish selectively bred for high and low levels of mirror aggression revealed specific transcriptomic signatures induced by selective breeding and mirror aggression and thus provides a large and novel resource of candidate genes for future study.
Topics: Aggression; Animals; Behavior, Animal; Gene Expression Profiling; Transcriptome; Zebrafish
PubMed: 35501893
DOI: 10.1186/s12915-022-01298-z -
Subjective aggression during alcohol and cannabis intoxication before and after aggression exposure.Psychopharmacology Sep 2016Alcohol and cannabis use have been implicated in aggression. Alcohol consumption is known to facilitate aggression, whereas a causal link between cannabis and aggression...
RATIONALE
Alcohol and cannabis use have been implicated in aggression. Alcohol consumption is known to facilitate aggression, whereas a causal link between cannabis and aggression has not been clearly demonstrated.
OBJECTIVES
This study investigated the acute effects of alcohol and cannabis on subjective aggression in alcohol and cannabis users, respectively, following aggression exposure. Drug-free controls served as a reference. It was hypothesized that aggression exposure would increase subjective aggression in alcohol users during alcohol intoxication, whereas it was expected to decrease subjective aggression in cannabis users during cannabis intoxication.
METHODS
Heavy alcohol (n = 20) and regular cannabis users (n = 21), and controls (n = 20) were included in a mixed factorial study. Alcohol and cannabis users received single doses of alcohol and placebo or cannabis and placebo, respectively. Subjective aggression was assessed before and after aggression exposure consisting of administrations of the point-subtraction aggression paradigm (PSAP) and the single category implicit association test (SC-IAT). Testosterone and cortisol levels in response to alcohol/cannabis treatment and aggression exposure were recorded as secondary outcome measures.
RESULTS
Subjective aggression significantly increased following aggression exposure in all groups while being sober. Alcohol intoxication increased subjective aggression whereas cannabis decreased the subjective aggression following aggression exposure. Aggressive responses during the PSAP increased following alcohol and decreased following cannabis relative to placebo. Changes in aggressive feeling or response were not correlated to the neuroendocrine response to treatments.
CONCLUSIONS
It is concluded that alcohol facilitates feelings of aggression whereas cannabis diminishes aggressive feelings in heavy alcohol and regular cannabis users, respectively.
Topics: Adolescent; Adult; Aggression; Alcohol Drinking; Alcoholic Intoxication; Cannabis; Case-Control Studies; Central Nervous System Depressants; Environmental Exposure; Ethanol; Female; Humans; Male; Marijuana Smoking; Young Adult
PubMed: 27422568
DOI: 10.1007/s00213-016-4371-1