Research Articles

Author(s): Pasztor, T.J., Smith, L.K., MacDonald, N.K., Michener, G.R., Pellis, S.M.
NIFP Rating: 5

play fighting in many species of squirrels can involve sexual play and aggressive play, both of which can lead to wrestling which appears superficially similar. Such convergence can make scoring of the relative frequencies of these two types of play difficult and can lead to the mistaken conclusion that they grade into one another. In […]

Subject(s):
Author(s): Pellis, S.M., Pellis, V.C.
NIFP Rating: 7

As pairs of male juvenile sibling rats that are housed together become sexually mature, they develop a dominance-subordinance relationship. These dominance relationships appear to be reflected in the play fighting of the pairmates both as juveniles and as young adults, in that the seemingly subordinate partner initiates more playful attacks at both ages. However, as […]

Author(s): Palagi, E.
NIFP Rating: 7

Adult strepsirrhines have been completely neglected in the study of animal play. I focused on adult play fighting and the role of tail-play as a signal in ringtailed lemurs (Lemur catta). Tail-play is performed during play fighting, when lemurs anoint or, more rarely, wave their tails toward the playmate. During the prereproductive period, male and […]

Author(s): Pellis, S.M., Pellis, V.C.
NIFP Rating: 3

Spider monkeys shake their heads so as to facilitate amicable social contact. This occurs frequently during vigorous play fighting, and so is common during the juvenile period. Occasionally, juvenile spider monkeys use headshakes during nonsocial locomotor play. In this study, head shaking in early infancy and in adulthood was studied in a captive troop of […]

Author(s): Davis, K.L, Montag, C.
NIFP Rating: 6

In the early nineties of the twentieth century Jaak Panksepp coined the term “Affective Neuroscience” (AN) today being accepted as a unique research area in cross-species brain science. By means of (i) electrical stimulation, (ii) pharmacological challenges, and (iii) brain lesions of vertebrate brains (mostly mammalian), Panksepp carved out seven primary emotional systems called SEEKING, […]

Author(s): Tuttle, B.
NIFP Rating: 5

Primal emotional-affective expressive

Author(s): Walker, Susan P., Chang, Susan M., Vera-Hernandez, Marcos, Grantham-McGregor, Sally
NIFP Rating: 8

OBJECTIVE: An estimated 178 million children younger than 5 years in developing countries experience linear growth retardation and are unlikely to attain their developmental potential. We aimed to evaluate adult benefits from early childhood stimulation and/or nutritional supplementation in growth-retarded children. METHODS: In Kingston, Jamaica, 129 growth-retarded children aged 9 to 24 months took part […]

Author(s): Wilson, B.J., Ray, D.
NIFP Rating: 3

The authors conducted a randomized controlled trial to investigate differences among 36 elementary school age children who received 16 sessions of child-centered play therapy and 35 children who were assigned to a waitlist control group. Pre- and postassessments were used to measure children’s levels of aggression, self-regulation, and empathy per parent and teacher report. Results […]

Author(s): Tal, R., Tal, K., Green, O.
NIFP Rating: 3

Sexual abuse by a perpetrator outside of the family is the most prevalent form of child sexual abuse. It is associated with serious consequences for both the child and his family. Surprisingly, however, the issue of extra-familial sexual abuse has received very little research and clinical attention. The purpose of the current study was to […]

Author(s): Tan, E.S.-H., Visch, V.
NIFP Rating: 10

The typical experience of narrative film is characterized by a remarkable intensity as to absorption and emotion. Current explanations attribute the experience to the realistic perceptual impact of the film. This theoretical article sets out to explain the experience as the result first of the film-viewer’s acts of imagination of fictional worlds. More specifically, it […]

Author(s): Piccininni, C., Michaelson, V., Janssen, I., Pickett, W.
NIFP Rating: ?

Exposures to outdoor environments have great potential to be protective factors for the mental health of young people. In a national analysis of Canadian adolescents, we explored how such exposures, as well as self-perceptions of connectedness with nature, each related to the prevalence of recurrent psychosomatic symptoms. The data source for this cross-sectional study, consisting […]

Author(s): Rosenbaum, M., Gabrielsen, T.P.
NIFP Rating: 1

Background: Early intervention in autism spectrum disorder (ASD) improves outcomes, but treatment access depends on early identification. Despite reliability of most autism diagnoses by age 24 months, the majority of children with autism do not receive comprehensive evaluations until after age 36 months. Although many possible reasons exist for delayed evaluations, the referral decision process […]

Author(s): Scopa, C., Palagi, E.
NIFP Rating: 7

Social play and tolerance are positively correlated and playful signals are more freely expressed in egalitarian than in despotic species. Macaque species are organized along a continuum from intolerant to tolerant social systems and, for this reason, they are good models to test some hypotheses about the possible linkage between communication and tolerance. We compared […]

Author(s): Pellis, S.M., Pellis, V.C.
NIFP Rating: 7

play fighting is a commonly reported form of play that involves competitive interactions that generally do not escalate to serious fighting. Although in many species what are competed over are the body targets that are bitten or struck in serious fighting, for many others, the competition can be over other forms of contact, such as […]

Subject(s):
Author(s): Pellis, S.M., Pellis, V.C.
NIFP Rating: 4

During competitive interactions, such as fighting and predation, animals perform various actions, some of which are easy to characterize and label, some of which are reliably repeated. Such ‘behavior patterns’ are often the measures of choice when comparing across species and experimental contexts. However, as Bob Blanchard and others have pointed out, such measurements can […]

Subject(s):
Author(s): Pellis, S.M., Pellis, V.C.
NIFP Rating: 4

During postweaning development, rats exhibit several well documented trends in their play fighting: (1) It peaks between 30-40 days and then declines with the approach of sexual maturity; (2) males initiate more play fights than females; and (3) the overall complexity of play fights, as expressed by such measures as duration of bouts, also decreases […]

Author(s): Pellis, S.M., Pellis, V.C., Dewsbury, D.A.
NIFP Rating: 2

play fighting in deer mice, Peromyscus maniculatus bairdii, prairie voles, Microtus ochrogaster, and montane voles, M. Montanus, was compared to that of laboratory rats, Rattus norvegicus. Play in rats appears more complex for two reasons: 1) more of the playful contacts elicit defensive behaviors, and 2) more of these defenses lead to counterattacks, and hence, […]

Author(s): Peterson, S.S., McIntyre, L.J., GlaÈs-Coutts, L.
NIFP Rating: 2

This article reports on collaborative action research in twelve northern rural and Indigenous communities in four Canadian provinces. Pre-kindergarten, kindergarten, grade one, and Aboriginal Head Start teachers worked with university researchers in three universities to create action research projects with the aim of supporting children’s oral language and writing through play in their classrooms. Inductive […]

Subject(s):
Author(s): Pellis, S.M., Burghardt, G.M., Palagi, E., Mangel, M.
NIFP Rating: 2

Why animals play has been a perennial question, but most of the thinking about this has been framed in terms of its fitness benefits. A review of our present knowledge about the comparative distribution of play suggests that such an approach that leads to claims that the “adaptive value of play is ” are misplaced. […]

Author(s): Pellis, S.M., Iwaniuk, A.N.
NIFP Rating: 2

Although play fighting, like play generally, is predominantly a feature of the juvenile phase, such behavior persists in the adults of many species. There are two major contexts in which adults engage in play fighting – with juveniles and with other adults. The least attention has been given to adult-adult play. However, one pattern that […]

Research Article Subjects

Search