Can Labor Market Policies Reduce Deaths of Despair?

Do minimum wages and the earned income tax credit (EITC) mitigate rising “deaths of despair?” We leverage state variation in these policies over time to estimate event study and difference-in-differences models of deaths due to drug overdose, suicide, and alcohol-related causes. Our causal models find no significant effects on drug or alcohol-related mortality, but do find significant reductions in non-drug suicides. A 10 percent minimum wage increase reduces non-drug suicides among low-educated adults by 2.7 percent, and the comparable EITC figure is 3.0 percent. Placebo tests and event-study models support our causal research design. Increasing both policies by 10 percent would likely prevent a combined total of more than 700 suicides each year.     

Active behaviors in the rat forced swimming test differentially produced by serotonergic and noradrenergic antidepressants

This study demonstrated that distinct patterns of active behaviors are produced by antidepressants that selectively inhibit norepinephrine (NE) or serotonin (5-HT) uptake in the rat forced swimming test (FST). A behavior sampling technique was developed to score the active behaviors swimming, climbing and diving, as well as immobility. The rat's behavior was recorded at the end of each 5-s period during the test session. The sampling technique was both reliable, as demonstrated by test-retest reliability and inter-rater reliability, and valid, as shown by comparison to the timing of behavior durations. Five different antidepressant drugs which block monoamine uptake and two 5-HT_1A receptor agonists were shown to decrease immobility in the FST; however, they produced distinct patterns of active behaviors. The selective NE uptake inhibitors desipramine and maprotiline selectively increased climbing, whereas the selective serotonin reuptake inhibitors (SSRIs) fluoxetine, sertraline and paroxetine selectively increased swimming. The 5-HT_1A receptor agonists 8-OH-DPAT and gepirone also selectively increased swimming. These results show that:1) SSRIs are not false negatives in the FST; 2) at least two behaviorally distinct processes occur in the FST; and 3) enhancement of NE neurotransmission may mediate climbing in the FST, whereas enhancement of 5-HT neurotransmission may mediate swimming.     

Effects of fixed-interval duration on the development of tolerance to decreased responding byl-nantradol

The effects of several types of antidepressants in a recently developed behavioural despair model, the tail-suspension test, are described. Drug effects on the automatically recorded duration of immobility and power of movements were measured in three strains of mice. Only in one strain (NMRI) did almost all antidepressants tested showed the expected reduction in duration of immobility. Tranquillizing drugs, but not stimulants, could be distinguished from antidepressants. The power of movements could not definitively be related to the pharmacological profile of the drugs tested. The use of the tail-suspension test as a rapid and highly predictive behavioural primary screen for antidepressant drugs is suggested.     

Potential anti-anxiety, anti-addictive effects of LY 354740, a selective group II glutamate metabotropic receptors agonist in animal models

Despite there being a lot of biochemical data about metabotropic glutamate (mGlu) receptors, our knowledge of the behavioural effects of mGlu receptor agonists/antagonists is still inadequate. LY 354740 is a systemically active agonist of group II mGlu receptors. After peripheral administration, LY 354740 produced anxiolytic-like effects in the conflict drinking test in rats and a four-plate test in mice. It was also found that LY 354740 decreased spontaneous locomotor activity in mice, but did not disturb motor coordination. In behavioural models of depression including the despair test and a tail suspension test, LY 354740 did not produce antidepressant-like effects. LY 354740 inhibited the naloxone-induced symptoms of morphine withdrawal in morphine-dependent mice. The above results indicate that agonists of group II mGlu receptors may play a role in the therapy of anxiety and/or drug-dependence states. The brain sites of action of LY 354740 need to be identified and the mechanism of both the above described effects remains to be elucidated.     

Attenuated response to nomifensine in rats during a swim test following lesion of the habenula complex

Male Lister rats with bilateral lesions of the habenula nuclei were observed during two consecutive phases of a swim test. During the first phase of the test, when escape was not possible, lesioned animals demonstrated fewer changes of behaviour. Lesioned animals failed to utilise an introduced external cue and escape route in the second part of the test. Control rats treated with the antidepressant nomifensine showed few changes of behaviour during the inescapable phase of the test but an enhanced ability to escape. Nomifensine produced no improvement of escape behaviour in lesioned animals, suggesting that this behavioural effect of nomifensine in controls is dependent on the habenula relay. The data also suggest that more than one response in swim tests can serve as an index of depression.     

Social isolation in prairie voles induces behaviors relevant to negative affect: toward the development of a rodent model focused on co-occurring depression and anxiety

Recent evidence suggests substantial overlap between mood and anxiety disorders, both in clinical presentation and associated features. A theoretical framework to account for this overlap focuses on negative affectivity, defined as the disposition to experience negative emotional states, including fear, sadness, and guilt. This model has been successful in explaining the co-occurrence of depressive and anxiety disorders in humans. As a next step, development of an animal model focused on both depression- and anxiety-relevant behaviors may advance understanding of depression-anxiety symptom overlap, relations of these disorders with associated medical conditions and responses to treatment. This study was designed to investigate inducible and quantifiable depression- and anxiety-like behaviors in prairie voles (Microtus ochrogaster). Adult, female prairie voles were exposed to 4 weeks of social pairing (control) or isolation, an established stressor for socially monogamous mammals (including humans). Operational measures of depression (sucrose intake and behaviors in the forced swim test), anxiety (behaviors in the elevated plus maze), and aggression (responses to an unrelated prairie vole pup) were investigated. Social isolation induced a progressive decline in sucrose intake and increased immobility time during the forced swim test. Social isolation also decreased the amount of time spent in the open arms of the elevated plus maze, and increased pup-directed attack behavior. The current findings suggest that isolation induces behaviors reflecting elevated negative affect. These results may provide a foundation for creating a rodent model to examine the mechanisms underlying comorbid mood and anxiety disorders.     

The effects of enriched environment on the behavioral and corticosterone response to methamphetamine in adolescent and adult mice

Methamphetamine alters behavior and the stress response system. Relatively little research has examined the effects of methamphetamine in adolescents and compared these effects to those in adults. Housing in enriched environments has been explored as one way to protect against the effects of methamphetamine, but the findings are conflicting and no study has examined how enriched environment may alter the behavioral and corticosterone responses to methamphetamine in adolescent and adult rodents. We examined the long‐term effects of methamphetamine exposure on anxiety, social behavior, behavioral despair, and corticosterone levels in adolescent and adult mice housed in enriched or isolated environments. Enriched environment did not alter the behavioral or corticosterone response to methamphetamine. Methamphetamine exposure decreased anxiety and increased behavioral despair in adult mice, but methamphetamine did not alter behavior in adolescent mice. There was no effect of methamphetamine on social behavior or corticosterone levels. Our findings demonstrate that the specific environmental enrichment paradigm used in this study was not sufficient to mitigate the behavioral effects of methamphetamine and that adolescent mice are relatively resistant to the effects of methamphetamine compared to adult mice.     

The effects of carbamazepine on two animal models of depression

Some clinical reports on antimanic, antidepressant and prophylactic effects of carbamazepine (CBZ) in manic-depressive illness have appeared since its initial use as an anticonvulsant drug. The present report deals with the effects of CBZ on two animal models of depression, namely the potentiation of amphetamine-induced anorexia, and the behavioral despair model. Carbamazepine (10, 20 or 40 mg/kg) neither modified the methamphetamine anorectic effect, nor induced anorexia when administered alone. Subacute and chronic administration of imipramine (4 or 15 mg/kg) decreased immobility of rats in the behavioral despair model. Subacute and chronic administration of CBZ (40 mg/kg) also decreased immobility, whereas the dose of 10 mg/kg CBZ was effective only after chronic treatment. It was concluded that CBZ is similar to atypical anti-depressants, since it did not potentiate the amphetamine-induced behavioral effect, but did have an effect on the behavioral despair model of depression.     

Of Rainbows and Tears: Exploring Hope and Despair in Trauma Therapy

Existential themes of hope and despair are central in the care of child and youth survivors of abuse trauma. Researchers have argued that acts of abuse can disrupt a person’s hope while shaking beliefs about purpose and meaning. Practitioners are called to implicitly offer their own hopeful faith in possibility to clients, especially in moments of client despair. However, trauma therapy offers a challenge to the practitioner, prompting us to question our own meaning frameworks. This paper considers issues of hope and despair in practice, for therapist and client, explores existential challenges for practitioners supporting survivors of trauma, and ponders the role of narratives in cultivating sustainable practice.     

Escapability and generalization: Effect on ‘behavioral despair’

Two experiments were conducted to investigate (1) whether ‘behavioral despair’ was related to inescapability of the warm swim and (2) whether ‘behavioral despair’ would generalize to a shock escape task. Results indicated that rats exhibited ‘behavioral despair’ independent of the escapability of the warm swim and that the phenomenon did not generalize to a shock escape task. Implications for the validity of the behavioral despair model are discussed.