Thursday, March 19, 2020

Possibility that individual groups of dopamine cells make a unique contribution to the processing of reward and aversion: Non-canonical dopamine pathways are excited in response to aversive stimuli

Aversion hot spots in the dopamine system. Jeroen P H Verharen, Yichen Zhu, Stephan Lammel. Current Opinion in Neurobiology, Volume 64, October 2020, Pages 46-52. https://doi.org/10.1016/j.conb.2020.02.002

Highlights
• DA neurons show high levels of anatomical and functional heterogeneity.
• Role for projection-defined DA neurons in processing aversive stimuli.
• Identification of aversive hot spots in vNAcMed, TS, mPFC, BLA.

Abstract: Through the development of optogenetics and other viral vector-based technologies, our view of the dopamine system has substantially advanced over the last decade. In particular, progress has been made in the reclassification of dopamine neurons based on subtypes displaying specific projections, which are associated with different features at the anatomical, molecular and behavioral level. Together, these discoveries have raised the possibility that individual groups of dopamine cells make a unique contribution to the processing of reward and aversion. Here, we review recent studies that have identified non-canonical dopamine pathways that are excited in response to aversive stimuli, including dopamine projections to the ventromedial shell of the nucleus accumbens, prefrontal cortex, tail of the striatum, and amygdala.

Decision-making competence may tap not only into fluid intelligence but also into motivation, emotion regulation, and experience (or crystallized intelligence)

Decision-Making Competence: More Than Intelligence? Wändi Bruine de Bruin, Andrew M. Parker, Baruch Fischhoff. Current Directions in Psychological Science, March 18, 2020
https://doi.org/10.1177/0963721420901592

Abstract: Decision-making competence refers to the ability to make better decisions, as defined by decision-making principles posited by models of rational choice. Historically, psychological research on decision-making has examined how well people follow these principles under carefully manipulated experimental conditions. When individual differences received attention, researchers often assumed that individuals with higher fluid intelligence would perform better. Here, we describe the development and validation of individual-differences measures of decision-making competence. Emerging findings suggest that decision-making competence may tap not only into fluid intelligence but also into motivation, emotion regulation, and experience (or crystallized intelligence). Although fluid intelligence tends to decline with age, older adults may be able to maintain decision-making competence by leveraging age-related improvements in these other skills. We discuss implications for interventions and future research.

Keywords: decision-making competence, individual differences, cognitive ability


Cuijpers and colleagues conducted a meta-analysis to answer the question whether psychotherapies (primarily CBT) for depression have comparable outcomes in all age groups across the life span

The Age of Depression and Its Treatments. Stefan G. Hofmann. JAMA Psychiatry, March 18, 2020. doi:10.1001/jamapsychiatry.2020.0158

Full text, references, etc., at the DOI above.

Depression is a serious and common mental health problem. Although a number of psychological and pharmacological treatments are available for this serious psychiatric condition, there is still a lot of room for improvement. As is true for virtually all mental disorders, the most common and comparatively most effective form of psychological treatment for depression is cognitive behavioral therapy (CBT).1

To advance and understand the treatments for this disorder, it is important to know when, how, and for whom a treatment works. In line with such a personalized approach to therapy, in this issue of JAMA Psychiatry, Cuijpers and colleagues2 conducted a meta-analysis to answer the question whether psychotherapies (primarily CBT) for depression have comparable outcomes in all age groups across the life span. Based on a meta-analytic review of 366 randomized clinical trials, this study found that treatments were less effective in children and adolescents compared with adults. The authors called for better psychological treatments in children and adolescents.

What might account for the observed results? What factors might have accounted for these findings aside from age? If age was in fact the primary reason for the results, why is psychotherapy in children and adolescents less effective? Is it possible that depression in children and adolescents is more severe and treatment resistant than the other age groups? These are the questions I will address in this commentary.

As is true for all meta-analyses, decisions have to be made that might have influenced the results. The study2 allowed different treatment formats, including individual sessions, group therapy, telephone consultations, and guided self-help treatments through the internet. It is quite reasonable to assume that the treatment formats are not used to the same extent by all age groups. Children are unlikely to use self-help guides, and very young children and older adults might be less likely to use the internet for their treatments than young adults, for example. We also know that some of these treatment formats are not as effective as others. Self-help guides, for example, may not be as effective as face-to-face treatments. This difference in treatment use might be an alternative explanation for the pattern of results.

There is also a well-known age-by-sex difference in the prevalence of depression.3 Until age 13 years, depression is equally common among boys and girls. After that age, depression becomes a lot more common in women and girls than men and boys. Therefore, any differences in the treatments between different age groups could also be attributable to differences in sex proportions between these groups. Similar arguments could be made for differences in socioeconomic status, social support, and even culture.

Finally, the number of studies included in the various age-group categories differ dramatically, with 242 studies examining middle-aged adults and only 13 studies examining children and 10 studies examining older adults.2 Not surprisingly, the 95% CI was a lot smaller for the treatment effect size for studies of the middle-aged adults compared with the treatment effect sizes of studies of the children and older adults. This may have also contributed to the pattern of results. Meta-analyses are powerful tools that need to be handled with great care.

Assuming that the findings2 are not explained by an artifact of some other variable, such as treatment use or sex, what could the results mean? Is it possible that depression is not the same disorder for all age groups? The DSM-5 distinguishes major depressive disorder, persistent depressive disorder (dysthymia), disruptive mood dysregulation disorder, premenstrual dysphoric disorder, substance/medication-induced depressive disorder, depressive disorder due to another medical condition, other specified depressive disorder, and unspecified depressive disorder. For all of these categories, age is a factor, and children with mood disorders have posed a number of diagnostic challenges. Perhaps one of the most controversial issues during the development of the DSM-5 was the diagnosis of bipolar disorder in children. To attempt to avoid the overdiagnosis of and treatment for bipolar disorder in children, the DSM-5 created a new diagnosis: disruptive mood dysregulation disorder. This diagnosis typically describes children 12 years or younger who show persistent irritability and frequent episodes of extreme behavioral dyscontrol.

There are other obvious age-associated differences in mood disorders. Children are much less likely to use substances of abuse than adults. Yet, we know that a large number of substances of abuse, such as some prescribed medications, as well as several medical conditions, can be associated with depressionlike phenomena. This fact is recognized in the diagnoses of substance/medication-induced depressive disorder and depressive disorder due to another medical condition. These patients will obviously require an intervention that also addresses the substance or medication to effectively target the depression. It is unclear how many patients in the meta-analysis met criteria for a substance-associated depression. Those patients were unlikely to be children.

The DSM-5 recognizes that in children and adolescents, the mood may be irritable and cranky rather than sad.4 A more chronic form of depression is diagnosed when the mood disturbance continues for at least 2 years in adults but only 1 year in children. Age further defines different subtypes of dysthymia, based on whether the onset is early (before age 21 years) or late (after age 21 years). These differences in age at onset and time course are fairly arbitrary, but they emphasize the importance of age when making a diagnosis.

Of particular relevance in the context of the study is the onset specifier. This specifier was in large part the result of studies conducted by Akiskal,5 who proposed that early-onset dysthymia is a low-grade characterological form of depression that develops gradually, whereas late-life dysthymia is an acute and more severe form of the disorder.

Although the early-onset vs late-onset specifier was not included for major depressive disorder, it has been suggested that a similar distinction should also be made for this disorder.6 Accordingly, early-onset chronic major depression might be a more severe form and associated with greater comorbidities than the late-onset subtype. This would explain why treatments are less effective in early-onset subtype of the disorder and therefore also in children and adolescents.

It is unclear why age appears to distinguish different forms of depressive states. It is quite possible that hormonal changes, and especially the influence of estrogen and testosterone on brain function and development among girls around puberty, might explain some of the results.7 Other possible explanations might be associated with the physical changes that occur during sexual maturity and the associated social conflicts and stress around gender roles.3 Whatever the reason, age (and sex) is a critical factor that needs to be considered for the diagnosis and treatment of depression. It is quite possible that we are dealing with different disorders, depending on the age and sex of the patient.8 Therefore, the same treatment might not be equally effective for all individuals at all ages. This questions the idea that depression is a monolithic entity and supports the call for a paradigm shift toward precision medicine in psychiatry.

Women rate sin stocks as less morally appropriate investment propositions and feel considerably less comfortable investing in controversial (but not conventional) stocks; sex differences are substantial

Niszczota, Paweł, and Michal Bialek. 2020. “Women Oppose Sin Stocks More Than Men Do.” PsyArXiv. March 18. doi:10.31234/osf.io/7a4cq

Abstract: We experimentally test whether men and women differ in their propensity to hold morally controversial (“sin”) stocks. Participants (N = 335) were recruited via Mechanical Turk and rated the moral appropriateness and level of comfort resulting from holding controversial and conventional stocks. Results show that women rate sin stocks as less morally appropriate investment propositions and feel considerably less comfortable investing in controversial (but not conventional) stocks. Sex differences in sin stock tolerance were substantial (d = .60) and remained significant after accounting for differences in investment knowledge and risk tolerance. We propose differences in deontological inclinations in men and women as a likely explanation for the observed effect, and discuss two important outcomes of these differences.


Does having children increase environmental concern? Testing parenthood effects with longitudinal data from the New Zealand Attitudes and Values Study

Does having children increase environmental concern? Testing parenthood effects with longitudinal data from the New Zealand Attitudes and Values Study. Taciano L. Milfont ,Wouter Poortinga,Chris G. Sibley. PLOS , March 18, 2020https://doi.org/10.1371/journal.pone.0230361

Abstract: Having children is a transformative experience and may change the way people think about the future. Parents invest time, energy and resources to ensure the survival and reproductive success of offspring. Having children may also induce environmental concerns and investments in actions aimed at guaranteeing the quality of natural resources available to offspring. However, there is limited empirical support for this parenthood effect, and little is known about how environmental attitudes and behaviour change over time following the birth of a child. This pre-registered study uses data from the first seven waves (2009–2015) of the New Zealand Attitudes and Values Study—a longitudinal national probability study of social attitudes, personality, and health outcomes—with multilevel interrupted time series analysis. Respondents’ belief in the reality and causes of climate change, sacrifices to standard of living to protect the environment, and changes in daily routine to protect the environment did not change significantly following the birth of a child; and nor were there changes in the underlying trends of attitudes or pre-birth anticipation effects. The study further found no gender differences in the attitudinal effects of childbirth. Additional exploratory analyses suggest that becoming a parent for the first time may increase beliefs in the reality of climate change but does not appear to change other environmental attitudes. Overall, our findings provide little empirical evidence for parenthood effects on environmentalism.


Discussion

Past correlational research has demonstrated that greater levels of pro-environmental engagement is associated with generativity and legacy concerns [1618], and higher levels of future thinking and endorsement of other-focused personal values [2021]. Experimental studies have also shown that priming individuals to envision their everyday life in the future [19], or to describe what they want to be remembered for by future generations [18] led to an increase in pro-environmental engagement. One logical extension of these findings showing an effect of other-focus and future-focus on environmental protection is to examine whether becoming a parent would influence one’s pro-environmental engagement. Parental investment in offspring should include considerations of the availability and quality of the natural environmental necessary for the survival and reproductive success of offspring.
Despite the theoretical and intuitive appeal of parenthood effects on environmentalism, a recent longitudinal study testing whether parenthood would increase pro-environmental engagement did not provide empirical support [22]. In the present study, we employed a distinct longitudinal dataset to test the hypothesis over up to six years. Across six dependent variables, we did not observe a single significant attitudinal effect related to the birth of a child. That is, we did not find any change in pro-environmental tendencies from before to after the birth of a child, and there were no changes in the underlying trends in pro-environmental tendencies either. In addition, the study found no gender differences in the attitudinal effects of childbirth. That is, null results in mean-level and slope-level effects were found for both mothers and fathers. Additional exploratory analyses suggest that becoming a parent for the first time may increase beliefs in the reality of climate change, but no effects were found for the other five environmental measures; and these effects for new parents must be interpreted with caution, as they were rendered non-significant when correcting for multiple comparisons.
Our findings provide little empirical evidence for parenthood effects on environmentalism, supporting the findings observed by Thomas and colleagues [22]. Together, analyses of two large, high-quality longitudinal datasets explicitly testing whether having children increase pro-environmental engagement do not seem to confirm intuitive predictions of parenthood effects. However, there are still a number of methodological and theoretical considerations to be kept in mind when interpreting the results.
Testing for parenthood effects as outlined in this paper requires a properly-sized longitudinal dataset of sufficient length. While the NZAVS is a high-quality longitudinal dataset with a large sample size (the sample contains over 23,000 unique individuals and more than 78,000 measurement occasions), there were only a limited number of childbirths, in particular of firstborns (of the 1,522 childbirths, around 400 were firstborns). That may not be sufficient to detect what are most likely modest effects. Another consideration is the age of mothers and fathers. The median age of women giving birth to a child is 30 in New Zealand and range between 13 and 53 [35]. The average age fathers is slightly higher (33 years), and around one in 100 babies has a father aged 50 years or over [36]. The average age of our sample is relatively high (i.e., 43.5 years at the time of Wave 1), meaning that many women in the sample are beyond childbearing age.
In addition, while the dataset included multiple waves of data collection and therefore was able to not only detect sudden mean-level but also more gradual slope-level changes before and after childbirth, the analyses were constricted to a six-year period. It is possible that the effect of parenthood on pro-environmental engagement is delayed over a longer period, and that (even) more measurement points are required to detect effects. Environmental attitudes and behaviour following childbirth may also have a U-shaped pattern. Initially, the impact of childbirth on environmental engagement may be negative because of pressures of looking after a young child, which then is followed by an increase in pro-environmental intentions/behaviour to ensure an environmental legacy is left for offspring. Indeed, Thomas et al. [22] observed detrimental effects of having a new-born child in the frequency of three behaviours (i.e., ‘wear more clothes instead of more heating’, ‘use public transport instead of car’ and ‘carshare with others’) that are harder to perform when parenting efforts takes precedent over other concerns. As discussed by Thomas et al. in relation to other findings [122337], the pressing concerns of new parents is to dedicate time, resources and energy for the immediate health and wellbeing of offspring, which should outweigh broader and longer-term concerns regarding environmental sustainability. It is possible that parental investment would start to include environmental considerations once the more immediate pressures of parenthood subside, and more measurement points are needed to capture longer-term patterns than were available in this study. Non-linear and delayed effects associated with having are a distinct possibility, as argued here, and should therefore be tested as part of future research using longitudinal datasets of sufficient length.
Major life events that are planned or at least can be anticipated may produce effects in preparation for the event. Indeed, childbirth has been associated with a number of anticipatory psychological and behavioural effects [24262738]. Anticipatory effects may bias the findings and can be missed with an insufficient number of pre-event measurements. In this study we modelled anticipatory effects in environmental attitudes and self-reported behavioural changes. Limited evidence was found for pre-birth changes, although there was a small but significant negative effect in reported changes in people’s daily environmental routines. This may indicate that possible negative changes in environmental habits may already be initiated in advance of the birth of a child. These anticipatory effects need to be studied in more detail because they may dampen or mask changes that new parents may make in response to the birth of a child.
Another reason for the absence of parenthood effects in this study may be that they only occur in specific groups. For example, Thomas and colleagues [22] found that parents with already high environmental concern show a small increase in the desire to act more sustainably after the birth of their first child. In the current paper we examined possible moderators, such as gender and parenthood status (i.e., whether participants already had a child or not), but there are other socio-demographic, psychological, and situational factors to consider. It is possible that, for example, socio-economic status and (pre-existing) environmental values may moderate potential parenthood effects. Economic circumstances may prevent new parents from making pro-environmental changes, and effects may be the most pronounced for those who are already concerned about the environment, and climate change in particular. Future research could study this in more detail, although other analytical techniques may be needed to study moderation effects as noted below.
In relation to the previous point, parenthood effects on environmentalism is based on the idea that the birth of a child enhances a parent’s legacy motivation. This is a yet untested assumption, mainly because legacy motivation measures have not been available in longitudinal datasets. Previous research has shown that a motivation to leave a positive legacy can be leveraged to increase engagement with climate change and other environmental problems [18], but it is still unclear whether this is also happening in response to having a child. There has been a call to understand environmentally relevant behaviour from a multilevel perspective to examine individual and contextual factors [39], and we extend this call by employing a multilevel analysis to examine changes over the life course. We believe theorising in the field will benefit from datasets that allows examination of developmental trajectories of environmental attitudes and behaviour and how they change as a result of major life events and transitions.
In this study we used a multilevel interrupted time series approach to study abrupt and more gradual changes before and after childbirth. This design is increasingly used in public health intervention [30] and life transition [24] research, as it allows the explicit modelling of the time-dependent nature of outcomes. Our study illustrates the implementation of this analytical strategy in the environmental domain, and previous studies have also used interrupted time series analysis to evaluate intervention outcomes of “natural experiments” with environmental consequences [4041]. As with any analytical technique there are limitations. Life transitions are usually associated with a number of changes, and those who experience a transition may be different from those who do not. Parenthood is usually planned in advance, and previous studies have shown that people without children and parents-to-be differ in socio-economic, social, and psychological characteristics (e.g., in personality see [4243]). While we were able to control for anticipation effects and for the socio-demographic variables of gender, age, ethnicity and socio-economic deprivation, biases may still occur due to selection effects. Not all participants may have the same propensity to have a child in a particular period, and this may produce or obscure an effect [4344].
Different techniques can be used to control for potential selection effects. A propensity score matching approach [44] can be used to match prospective parents with non-parents that have similar baseline characteristics. Balancing characteristics that determine the propensity to experience a specific event or an intervention has become widespread in life transition research to avoid biased treatment effects [524274546]. It would be necessary to explore propensity effects with further moderation analyses and to increase confidence in the evidence so far that there are no changes in environmental attitudes and behaviour following childbirth.

In conclusion, we examined whether the birth of a new chid increased climate change beliefs and pro-environmental attitudes and behavioural intentions of parents. Overall, our longitudinal analysis shows no mean-level or rate-change effects in the environmental measures examined, disconfirming predictions of parenthood effect on environmentalism. There were no changes observed in either mothers or fathers, similarly disconfirming gender or ‘parental role’ interpretations of possible parenthood effects [1]. While there was a small effect indicating that becoming a parent for the first time may increase beliefs in the reality of climate change, these effects should be considered preliminary given the exploratory nature of those analyses and the fact this becomes statistically non-significant when correcting for multiple comparison. The study contributes to theoretical and methodological advances in environmental decision-making research but should be expanded upon with further analyses to address uncertainties about the specific temporal pattern of effects and potential selection and anticipation effects in becoming a parent. We hope possible parenthood effects on environmentally relevant variables continue to be explored in future studies.

#TheDress is perceived by some people as black and blue while others perceive it as white and gold. We have previously shown that the first encounter with #TheDress strongly biases its perception

How stable is perception in #TheDress and #TheShoe? Leila Drissi-Daoudi et al. Vision Research, Volume 169, April 2020, Pages 1-5. https://doi.org/10.1016/j.visres.2020.01.007

Abstract: #TheDress is perceived by some people as black and blue while others perceive it as white and gold. We have previously shown that the first encounter with #TheDress strongly biases its perception. This percept remained stable during the experiment, suggesting a role of one-shot learning. #TheShoe is another image that elicits similar bimodal color percepts. Here, we investigated how percepts change over time in both #TheShoe and #TheDress. First, we show that the important role of one-shot learning, which we found for #TheDress extends to #TheShoe. Similarly to our previous results with the dress, hiding large parts of the image with occluders biased the percept of the shoe. The percept did not change for the majority of observers when the occluders were removed. Second, we investigated if and how percepts switch over a time course of 14 days. We found that although some observers experienced percept switches, the percept was largely stable for most observers.

Keywords: #TheDress#TheShoeContextual processingOne-shot learningPerceptual dynamics