Trading off switch costs and stimulus availability benefits: An investigation of voluntary task-switching behavior in a predictable dynamic multitasking environment

In the present study, we introduce a novel, self-organized task-switching paradigm that can be used to study more directly the determinants of switching. Instead of instructing participants to randomly switch between tasks, as in the classic voluntary task-switching paradigm (Arrington & Logan, 2004), we instructed participants to optimize their task performance in a voluntary task-switching environment in which the stimulus associated with the previously selected task appeared in each trial after a delay. Importantly, the stimulus onset asynchrony (SOA) increased further with each additional repetition of this task, whereas the stimulus needed for a task switch was always immediately available. We conducted two experiments with different SOA increments (i.e., Exp. 1a = 50 ms, Exp. 1b = 33 ms) to see whether this procedure would induce switching behavior, and we explored how people trade off switch costs against the increasing availability of the stimulus needed for a task repetition. We observed that participants adapted their behavior to the different task environments (i.e., SOA increments) and that participants switched tasks when the SOA in task switches approximately matched the switch costs. Moreover, correlational analyses indicated relations between individual switch costs and individual switch rates across participants. Together, these results demonstrate that participants were sensitive to the increased availability of switch stimuli in deciding whether to switch or to repeat, which in turn demonstrates flexible adaptive task selection behavior. We suggest that performance limitations in task switching interact with the task environment to influence switching behavior.     

Imperfection,Indecision, and Hoarding

Hoarding disorder is a new DSM-5 disorder that causes functional impairment and affects 2 to 6% of the population (Frost and Steketee 2014). The current study evaluated a multiple mediation model with 243 undergraduate women in which indecisiveness (VOCI; Thordarson et al. Behaviour Research and Therapy, 42(11), 1289-1314, 2004) and decisional procrastination (DPS; Mann 1982) mediated the relationship between dimensions of perfectionism (F-MPS-B; Burgess et al. 2016a) and hoarding behavior (SI-R; Frost et al. Behaviour Research And Therapy, 42(10), 1163–1182, 2004) and excessive acquiring (CAS; Frost et al. Annual Review of Clinical Psychology, 8, 219–242, 2012). Multiple mediational analyses indicated a significant indirect effect for decisional procrastination, but not indecisiveness, in mediating evaluative concerns (but not striving) to SI-R Total, SI-R Clutter, SIR Excessive Acquisition, and both CAS subscales. Both mediators were significant pathways between evaluative concerns and SI-R Difficulty Discarding. These findings support a cognitive behavioral model of hoarding, suggesting that evaluative concerns produces problems in decision-making that influence acquisition, discarding, and clutter.     

Temporal encoding strategies result in boosts to final free recall performance comparable to spatial ones

The method of loci is a highly effective mnemonic that recruits existing salient memory for spatial locations and uses the information as a scaffold for remembering a list of items (Yates, 1966). One possible account for the effectiveness of the spatial method of loci comes from the perspective that it utilizes evolutionarily preserved mechanisms for spatial navigation within the hippocampus (Maguire et al. in Proceedings of the National Academy of Sciences, 97(8), 4398–4403, 2000; O’Keefe & Nadel, 1978; Rodriguez et al. in Brain Research Bulletin, 57(3), 499–503, 2002). Recently, though, neurons representing temporal information have also been described within the hippocampus (Eichenbaum in Nature Reviews Neuroscience, 15(11), 732–744, 2014; Itskov, Curto, Pastalkova, & Buzsáki in The Journal of Neuroscience, 31(8), 2828–2834, 2011; MacDonald, Lepage, Eden, & Eichenbaum in Neuron, 71(4), 737–749, 2011; Mankin et al. in Proceedings of the National Academy of Sciences, 109(47), 19462–19467, 2012; Meck, Church, & Matell in Behavioral Neuroscience, 127(5), 642, 2013), challenging the primacy of spatial-based functions to hippocampal processing. Given the presence of both spatial and temporal coding mechanisms within the hippocampus, we predicted that primarily temporal encoding strategies might also enhance memory. In two different experiments, we asked participants to learn lists of unrelated nouns using the (spatial) method of loci (i.e., the layout of their home as the organizing feature) or using two novel temporal methods (i.e., autobiographical memories or using the steps to making a sandwich). Participants’ final free recall performance showed comparable boosts to the method of loci for both temporal encoding strategies, with all three scaffolding approaches demonstrating performance well above uninstructed free recall. Our findings suggest that primarily temporal representations can be used effectively to boost memory performance, comparable to spatial methods, with some caveats related to the relative ease with which participants appear to master the spatial versus temporal methods.     

Deference,respect and intensionality

This paper is about the standard Reflection Principle (van Fraassen in J Philos 81(5):235–256, 1984) and the Group Reflection Principle (Elga in Nous 41(3):478–502, 2007; Bovens and Rabinowicz in Episteme 8(3):281–300, 2011; Titelbaum in Quitting certainties: a Bayesian framework modeling degrees of belief, OUP, Oxford, 2012; Hedden in Mind 124(494):449–491, 2015). I argue that these principles are incomplete as they stand. The key point is that deference is an intensional relation, and so whether you are rationally required to defer to a person at a time can depend on how that person and that time are designated. In this paper I suggest a way of completing the Reflection Principle and Group Reflection Principle, and I argue that so completed these principles are plausible. In particular, they do not fall foul of the Sleeping Beauty case (Elga in Analysis 60(2):143–147, 2000), the Cable Guy Paradox (Hajek in Analysis 65(286):112–119, 2005), Arntzenius’ prisoner cases (Arntzenius in J Philos, 100(7):356–370, 2003), or the Puzzle of the Hats (Bovens and Rabinowicz in Episteme 8(3):281–300, 2011).     

From anticipation to integration: the role of integrated action-effects in building sensorimotor contingencies

Ideomotor approaches to action control have provided evidence that the activation of an anticipatory image of previously learned action-effects plays a decisive role in action selection. This study sought for converging evidence by combining three previous experimental paradigms: the response–effect compatibility protocol introduced by Kunde (Journal of Experimental Psychology: Human Perception and Performance, 27(2), 387–394, 2001), the acquisition-test paradigm developed by Elsner and Hommel (Journal of Experimental Psychology: Human Perception and Performance, 27(1), 229, 2001), and the object-action compatibility manipulation of Tucker and Ellis (Visual Cognition, 8(6), 769–800, 2001). Three groups of participants first performed a response–effect compatibility task, in which they carried out power and precision grasps that produced either grasp-compatible or grasp-incompatible pictures, or no action effects. Performance was better in the compatible than in the incompatible group, which replicates previous observations and extends them to relationships between grasps and objects. Then, participants were to categorize object pictures by carrying out grasp responses. Apart from replicating previous findings of better performance in trials in which object size and grasp type was compatible, we found that this stimulus–response compatibility effect depended on previous response-effect learning. Taken together, these findings support the assumption that the experience of action–effect contingencies establishes durable event files that integrate representations of actions and their effects.     

An examination of the processing capacity of features in the Thatcher illusion

Detection of the Thatcher illusion (Thompson, Perception, 9:483–484, 1980) is widely upheld as being dependent on configural processing (e.g., Bartlett & Searcy, Cognitive Psychology, 25:281–316, 1993; Boutsen, Humphreys, Praamstra, & Warbrick, NeuroImage, 32:352–367, 2006; Donnelly & Hadwin, Visual Cognition, 10:1001–1017, 2003; Leder & Bruce, Quarterly Journal of Experimental Psychology, 53A:513–536, 2000; Lewis, Perception, 30:769–774, 2001; Maurer, Grand, & Mondloch, Trends in Cognitive Sciences, 6:255–260, 2002; Stürzel & Spillmann, Perception, 29:937–942, 2000). Given that supercapacity processing accompanies configural processing (see Wenger & Townsend, 2001), supercapacity processing should occur in the processing of Thatcherised upright faces. The purpose of this study was to test for evidence that the grotesqueness of upright Thatcherised faces results from supercapacity processing. Two tasks were employed: categorisation of a single face as odd or normal, and a same/different task for sequentially presented faces. The stimuli were typical faces, partially Thatcherised faces (either eyes or mouth inverted) and fully Thatcherised faces. All of the faces were presented upright. The data from both experiments were analysed using mean response times and a number of capacity measures (capacity coefficient, the Miller and Grice inequalities, and the proportional-hazards ratio). The results of both experiments demonstrated some evidence of a redundancy gain for the redundant-target condition over the single-target condition, especially in the response times in Experiment 1. However, there was very limited evidence, in either experiment, that the redundancy gains resulted from supercapacity processing. We concluded that the oddity signalled by inversion of eyes and mouths does not arise from positive interdependencies between these features.     

Norms of valence and arousal for 14,031 Spanish words

Most current models of research on emotion recognize valence (how pleasant a stimulus is) and arousal (the level of activation or intensity that a stimulus elicits) as important components in the classification of affective experiences (Barrett, 1998; Kuppens, Tuerlinckx, Russell, & Barrett, 2012). Here we present a set of norms for valence and arousal for a very large set of Spanish words, including items from a variety of frequencies, semantic categories, and parts of speech, including a subset of conjugated verbs. In this regard, we found that there were significant but very small differences between the ratings for conjugations of the same verb, validating the practice of applying the ratings for infinitives to all derived forms of the verb. Our norms show a high degree of reliability and are strongly correlated with those of Redondo, Fraga, Padrón, and Comesaña’s (2007) Spanish version of the influential Affective Norms for English Words (Bradley & Lang, 1999), as well as those from Warriner, Kuperman, and Brysbaert (2013), the largest available set of emotional norms for English words. Additionally, we included measures of word prevalence—that is, the percentage of participants that knew a particular word—for each variable (Keuleers, Stevens, Mandera, & Brysbaert, 2015). Our large set of norms in Spanish not only will facilitate the creation of stimuli and the analysis of texts in that language, but also will be useful for cross-language comparisons and research on emotional aspects of bilingualism. The norms can be downloaded and available as a supplementary materials to this article.     

A Geometric Analysis of When Fixed Weighting Schemes Will Outperform Ordinary Least Squares

Many researchers have demonstrated that fixed, exogenously chosen weights can be useful alternatives to Ordinary Least Squares (OLS) estimation within the linear model (e.g., Dawes, Am. Psychol. 34:571–582, 1979; Einhorn &; Hogarth, Org. Behav. Human Perform. 13:171–192, 1975; Wainer, Psychol. Bull. 83:213-217, 1976). Generalizing the approach of Davis-Stober, Dana, and Budescu (Psychometrika 75:521–541, 2010b), I present an analytic method to determine when a choice of fixed weights will incur less mean squared error than OLS as a function of sample size, error variance, and model predictability. Geometrically, I solve for the region of population β that favors a choice of fixed weights over OLS. I derive closed-form upper and lower bounds on the volume of this region, giving tight bounds on the proportion of population β favoring a choice of fixed weights. I illustrate this methodology with several examples and provide a MATLAB^© (The MathWorks, Matlab software, version 2009b, 2010) programming implementation of the major results.     

Modulation of additive and interactive effects by trial history revisited

Masson and Kliegl (Journal of Experimental Psychology: Learning, Memory, and Cognition, 39, 898–914, 2013) reported evidence that the nature of the target stimulus on the previous trial of a lexical decision task modulates the effects of independent variables on the current trial, including additive versus interactive effects of word frequency and stimulus quality. In contrast, recent reanalyses of previously published data from experiments that, unlike the Masson and Kliegl experiments, did not include semantic priming as a factor, found no evidence for modulation of additive effects of frequency and stimulus quality by trial history (Balota, Aschenbrenner, & Yap, Journal of Experimental Psychology: Learning, Memory, and Cognition, 39, 1563–1571, 2013; O’Malley & Besner, Journal of Experimental Psychology: Learning, Memory, and Cognition, 34, 1400–1411, 2013). We report two experiments that included semantic priming as a factor and that attempted to replicate the modulatory effects found by Masson and Kliegl. In neither experiment was additivity of frequency and stimulus quality modulated by trial history, converging with the findings reported by Balota et al. and O’Malley and Besner. Other modulatory influences of trial history, however, were replicated in the new experiments and reflect potential trial-by-trial alterations in decision processes.     

May I have your attention please: Binding of attended but response-irrelevant features

The feature codes of stimuli and responses can be integrated, and if a stimulus is repeated it can retrieve the previously integrated response. Furthermore, even irrelevant features can be integrated and, upon repetition, retrieve the response. Yet the role of attention in feature integration and retrieval is not clearly understood. Some theories assume a central role of attention (e.g., Logan, 1988; Treisman & Gelade, 1980), but other studies have shown no influence of attention on feature binding (e.g., Hommel, 2005). In the present experiments the effect of attention on the integration of two different response-irrelevant features of the same stimulus was examined. In two experiments, participants responded to the color (response feature) of word stimuli, while two irrelevant features of the words (word type and valence) were systematically varied. Participants’ attention was directed to either one or the other of the response-irrelevant features by asking participants to report that feature at the end of the trial. Feature–response binding effects in the color task were observed to be stronger for the attended response-irrelevant feature. These results indicate that feature binding is not only very flexible but also sensitive to the distribution of attention. It is also automatic, in the sense that as long as attention is available, feature binding occurs irrespective of the task-specific demands.     

Modus Ponens Under the Restrictor View

There is a renewed debate about modus ponens. Strikingly, the recent counterexamples in Cantwell (Theoria, 74, 331–351 2008), Dreier (2009) and MacFarlane and Kolodny (The Journal of Philosophy, 107, 115–143 2010) are generated by restricted readings of the ‘if’-clause. Moreover, it can be argued on general grounds that the restrictor view of conditionals developed in Kratzer (1986) and Lewis (1975) leads to counterexamples to modus ponens (cp. Charlow Synthese, 190, 2291–2323 2013; Khoo Philosophical Studies, 166, 153–64 2013). This paper provides a careful analysis of modus ponens within the framework of the restrictor view. Despite appearances to the contrary, there is a robust sense in which modus ponens is valid, owing to the fact that conditionals do not only allow for restricted readings but have bare interpretations, too.     

Distilling Common History and Practice Elements to Inform Dissemination: Hanf-Model BPT Programs as an Example

There is a shift in evidence-based practice toward an understanding of the treatment elements that characterize empirically supported interventions in general and the core components of specific approaches in particular. The evidence base for behavioral parent training (BPT) and the standard of care for early-onset disruptive behavior disorders (oppositional defiant disorder and conduct disorder), which frequently co-occur with attention deficit hyperactivity disorder, are well established, yet an ahistorical, program-specific lens tells little regarding how leaders, University of Oregon Medical School, shaped the common practice elements of contemporary evidence-based BPT. Accordingly, this review summarizes the formative work of Hanf, as well as the core elements, evolution, and extensions of her work, represented in Community Parent Education (COPE; (Cunningham et al. in J Child Psychol Psychiatry 36:1141–1159, 1995; Cunningham et al. in COPE, the community parent education program: large group community-based workshops for parents of 3- to 18-year-olds, COPE Works, Hamilton, 2009), Defiant Children (DC; (Barkley in Defiant children: a clinician’s manual for assessment and parent training, Guilford Press, New York, 1987; Barkley in Defiant children: a clinician’s manual for assessment and parent training, Guilford Press, New York, 2013), Helping the Noncompliant Child (HNC; Forehand and McMahon in Helping the noncompliant child: a clinician’s guide to parent training, Guilford Press, New York, 1981; McMahon and Forehand in Helping the noncompliant child: family-based treatment for oppositional behavior, 2nd ed., Guilford Press, New York, 2003), Parent–child interaction therapy (PCIT; Eyberg and Robinson in J Clin Child Adolesc Psychol 11:130–137, 1982. doi:10.1080/15374418209533076; Eyberg in Child Fam Behav Ther 10:33–46, 1988; Eyberg and Funderburk in Parent–child interaction therapy protocol, PCIT International, Gainesville, 2011), and the Incredible Years (IY; (Webster-Stratton in Behav Ther 12:634–642, 1981. doi:10.1016/S0005-7894(81)80135-9; Webster-Stratton in J Pediatr Psychol 7:279–294, 1982. doi:10.1093/jpepsy/7.3.279; Webster-Stratton in The incredible years: parents and children series. Leader’s guide: preschool version of BASIC (ages 3–6 years, The Incredible Years, Seattle, 2008). Our goal is not to provide an exhaustive review of the evidence base for the Hanf-Model programs, rather our intention is to provide a template of sorts from which agencies and clinicians can make informed choices about how and why they are using one program versus another, as well as how to make inform flexible use one program or combination of practice elements across programs, to best meet the needs of child clients and their families. Clinical implications and directions for future work are discussed.     

Probabilistic Opinion Pooling with Imprecise Probabilities

The question of how the probabilistic opinions of different individuals should be aggregated to form a group opinion is controversial. But one assumption seems to be pretty much common ground: for a group of Bayesians, the representation of group opinion should itself be a unique probability distribution (Madansky [44]; Lehrer and Wagner [34]; McConway Journal of the American Statistical Association, 76(374), 410–414, [45]; Bordley Management Science, 28(10), 1137–1148, [5]; Genest et al. The Annals of Statistics, 487–501, [21]; Genest and Zidek Statistical Science, 114–135, [23]; Mongin Journal of Economic Theory, 66(2), 313–351, [46]; Clemen and Winkler Risk Analysis, 19(2), 187–203, [7]; Dietrich and List [14]; Herzberg Theory and Decision, 1–19, [28]). We argue that this assumption is not always in order. We show how to extend the canonical mathematical framework for pooling to cover pooling with imprecise probabilities (IP) by employing set-valued pooling functions and generalizing common pooling axioms accordingly. As a proof of concept, we then show that one IP construction satisfies a number of central pooling axioms that are not jointly satisfied by any of the standard pooling recipes on pain of triviality. Following Levi (Synthese, 62(1), 3–11, [39]), we also argue that IP models admit of a much better philosophical motivation as a model of rational consensus.     

Use of the familiarity difference cue in inferential judgments

The familiarity difference cue has been regarded as a general cue for making inferential judgments (Honda, Abe, Matsuks, & Yamagishi in Memory and Cognition, 39(5), 851–863, 2011; Schwikert & Curran in Journal of Experimental Psychology: General, 143(6), 2341–2365, 2014). The current study tests a model of inference based on familiarity differences that encompasses the recognition heuristic (Goldstein & Gigerenzer, 1999, Goldstein & Gigerenzer in Psychological Review, 109(1), 75–90, 2002). In two studies, using a large pool of stimuli, participants rated their familiarity of cities and made choices on a typical city-size task. The data were fitted with the r-s model (Hilbig, Erdfelder, & Pohl in, Journal of Experimental Psychology: Learning Memory and Cognition, 37(4), 827–839, 2011), which was adapted to include familiarity differences. The results indicated that people used the familiarity difference cue because the participants ignored further knowledge in a substantial number of cases when the familiarity difference cue was available. An analysis of reaction-time data further indicated that the response times were shorter for heuristic judgments than for knowledge-only-based judgments. Furthermore, when knowledge was available, the response times were shorter when knowledge was congruent with a heuristic cue than when it was in conflict with it. Differences between the familiarity difference cue and the fluency heuristic (Schooler & Hertwig, 2005, Psychological Review, 112, 610–628) are discussed.     

Gender Differences in Experiences with Couples Treatment for IPV

Evidence suggests that conjoint treatment can be effective for certain violent couples in certain situations (Finkel in Rev Gen Psychol 11:193–207, 2007; LaTaillade et al. in J Cogn Psychother 20:393–410, 2006; Fals-Stewart et al. in J Consult Clin Psych 73:239–248, 2005; Stith et al. in J Marital Fam Ther 29(3):407–426, 2003). However, not as much is known about which aspects of conjoint treatment make a difference, nor if male and female participants experience these elements of treatment differently. Knowing which components of couples’ treatment clients perceive as helpful—and whether their perceptions differ by gender—will allow us to redefine models with an eye toward making them more effective. In this study we used qualitative methods to examine the aspects of a particular couples’ treatment program (Stith and McCollum in Aggress Violent Beh 16(4):312–318, 2011) that clients found useful while also considering the differences between men’s and women’s responses. Fourteen couples, in which the male had been identified as the primary aggressor, were interviewed multiple times to gain their perspectives about components of the program they found helpful and their suggestions for program improvement. Themes are analyzed by gender. Implications for treatment and future research are provided.     

God’s Melancholia

Donald Capps’s (Capps 1997, 2001, 2002a, b) male melancholia theory has been of interest to me during the past few years (Carlin 2003, 2006, 2007), and Capps (2004, 2007a, b) himself has been publishing more on the topic. In his psychobiographical book on Jesus, Capps (2000) notes that psychologists of religion have been reluctant to psychoanalyze Jesus, and here I note that even fewer have been willing to diagnose God, one recent exception being J. Harold Ellens (2007). In this article, I explore the melancholia issue further, this time applying the theory to God by means of theological concepts that deal with the Trinity and the passion of God. And while this article is playful (Pruyser 1974; cf. Dykstra 2001), the upshot is more serious: If men are incurably religious and melancholic, as Capps argues, and if men, by and large, are the creators of religion, wouldn’t one expect to find traces of this melancholy in religion, particularly in its sacred texts and doctrines? By identifying these tendencies in religion, especially in God, the pastoral psychologist, I believe, is helping contemporary Christian men—especially fathers and sons—recognize their own melancholy selves and, perhaps, helping them get along a little better.     

The Effects of the Activation of Money and Credit Card vs. that of Activation of Spirituality – Which One Prompts Pro-Social Behaviours?

Pro-social behaviours may be prompted or inhibited depending on the situation. Numerous experiments show that, when exposed to the idea of money, people are less willing to help, devote their time or share their resources with others (Vohs et al. Science, 314, 1154–1156, 2006, Current Directions in Psychological Science, 17(3), 208–212, 2008). Conversely, when exposed to the idea of spirituality, they often cheat less and are more willing to help others (Mazar and Ariely Journal of Marketing Research, 45, 633–644, 2008; Randolph-Seng and Nielsen The International Journal for the Psychology of Religion, 17(4), 303–315, 2007). The aim of this article is to present the results of two experiments in which we activated thoughts about money, i.e. both cash and credit cards, and thoughts about spirituality in order to find out in what way these two kinds of activation may influence pro-social behaviours. In experiment 1, participants, when reminded of money, offered lower donations to others whereas those reminded of spirituality offered higher donations. In experiment 2, those participants reminded of money offered to devote less time to help others whereas those reminded of spirituality offered to devote more time to help others.     

Transgender Dispossession in <Emphasis Type="Italic">Transparent</Emphasis>: Coming Out as a Euphemism for Honesty

Since the 1990s, television narratives have increased visibility for LGBTQIA (Lesbian, Gay, Bisexual, Transgender, Queer/Questioning, Intersex, and Asexual) individuals and underscored the need for a deep exploration of the heterosexism (homophobia) that pervades much mainstream American programming (Lee and Meyer in Sex Cult 141:234–250, 2010; Manuel in Soc Semiot 19(3):275–291, 2009). One such serial, Transparent, has been credited by many major media outlets with transforming the way Americans think about transgender, gender expansive (Ehrensaft in Gender born gender made, The Experiment, New York, 2011), or trans*, individuals. Exploring Transparent through Butler and Athanasiou’s (Dispossession: the performative in the political, Polity Press, Cambridge, 2013) framework of dispossession, this essay argues that the depiction of dispossession in Transparent may serve to hypostasize the gender binary rather than to disrupt it. By severing the rhetorical act of “coming out” from the historical pathologization of non-normative sexualities and gender expansiveness in America, Transparent risks undoing the very social progress that it has the potential to further. While the show could powerfully disrupt cisgender privilege (Brydum in The true meaning of the word cisgender, 2015), as of its second season, instead, it merely illustrates how the media produced trans* “coming out” narrative all too often reifies the gender binary and cisgender privilege. Although it is tempting to praise Transparent for its representation of gender expansiveness, its problematic use of the “coming out” rhetoric should not be ignored.     

Do gray wolves (<Emphasis Type="Italic">Canis lupus</Emphasis>) support pack mates during aggressive inter-pack interactions?

For group-living mammals, social coordination increases success in everything from hunting and foraging (Crofoot and Wrangham in Mind the Gap, Springer, Berlin, 2010; Bailey et al. in Behav Ecol Sociobiol 67:1–17, 2013) to agonism (Mosser and Packer in Anim Behav 78:359–370, 2009; Wilson et al. in Anim Behav 83:277–291, 2012; Cassidy et al. in Behav Ecol 26:1352–1360, 2015). Cooperation is found in many species and, due to its low costs, likely is a determining factor in the evolution of living in social groups (Smith in Anim Behav 92:291–304, 2014). Beyond cooperation, many mammals perform costly behaviors for the benefit of group mates (e.g., parental care, food sharing, grooming). Altruism is considered the most extreme case of cooperation where the altruist increases the fitness of the recipient while decreasing its own fitness (Bell in Selection: the mechanism of evolution. Oxford University Press, Oxford 2008). Gray wolf life history requires intra-pack familiarity, communication, and cooperation in order to succeed in hunting (MacNulty et al. in Behav Ecol doi: 10.1093/beheco/arr159 2011) and protecting group resources (Stahler et al. in J Anim Ecol 82: 222–234, 2013; Cassidy et al. in Behav Ecol 26:1352–1360, 2015). Here, we report 121 territorial aggressive inter-pack interactions in Yellowstone National Park between 1 April 1995 and 1 April 2011 (>5300 days of observation) and examine each interaction where one wolf interferes when its pack mate is being attacked by a rival group. This behavior was recorded six times (17.6 % of interactions involving an attack) and often occurred between dyads of closely related individuals. We discuss this behavior as it relates to the evolution of cooperation, sociality, and altruism.     

Sex-Specific Effect of Recalled Parenting on Affective and Cognitive Empathy in Adulthood

Previous research has demonstrated the influence of parenting on the development of children’s empathy. However, few studies have considered the impact of parents on empathy in adulthood, specific components of empathy, or the importance of parent and child biological sex. In the present study, 226 participants (71 men) completed online versions of the Parental Bonding Instrument (Parker et al. British Journal of Medical Psychology, 52, 1–10 1979), Empathy Quotient (Baron-Cohen and Wheelwright Journal of Autism and Developmental Disorders, 34, 163–175 2004), and Interpersonal Reactivity Index (Davis JSAS Catalog of Selected Documents in Psychology, 10, 85 1980). Paternal care and overprotection influenced affective empathy in men, whilst maternal overprotection predicted affective empathy in women. Further, maternal care related to cognitive empathy in men, whilst none of the parental care variables related to cognitive empathy in women. Findings are discussed in relation to sex differences in childhood parenting experiences on adult cognitive and affective empathy.