17 resultados para cognitive studies and clown

em Brock University, Canada


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The purpose ofthe study was to examine the relationshq) between self-serving cognitive distortions and involvement in bullying behaviours. While relationships were e}q)k)red for both bullies and victims, the bully represented the main focus ofthis research. The participants ofthis study were 206 elementary school children in grades 5, 6, 7, and 8 from a school board in South Western Ontario. Participants conq>leted a 2- part self-report questionnaire within a 1-week time period. Part I aimed to measure self-serving cognitive distortions, while Part II was designed to assess selfreports of bullying behaviours. Analyses revealed that a significant direct relationship existed between children's self-serving cognitive distortions and bullying others. More specifically, children's self-serving cognitive distortions were moderately correlated with bullying others (r = .50, p< 0.01). This finding was consistent for both male and female participants. In addition, significant moderate correlations also existed between each ofthe 9 subscales ofself-serving cognitive distortions and bullying others. In regard to the relationship between children's self-serving cognitive distortions and victimization, a low significant direct relationshq) was found (r = .22 p<0.01). This finding was consistent for both male and female participants. The results ofthis study are discussed in terms oftheir theoretical, as well as applied implications.

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Research has noted both physical and psychosocial benefits when children participate in regular physical activity. Recent studies are indicating that there may also be academic benefits and that students may be more efficient learners with participation in physical activity. This study investigated the influence of acute moderate-to-vigorous physical activity on four cognitive functions: planning, attention, simultaneous processing, and successive processing. Three classes (59 students) were each tested twice using a balanced design (intervention, balance, and control groups). It was found that the intervention group had a large increase in planning abiHty (ES = 1.67) when compared to the balance (ES = .80) and control (ES = -.89) groups. On the three remaining cognitive functions, the intervention group showed effect sizes similar to that of the balance and control groups. These results indicate that improved planning after physical activity may playa role in improving student performance.

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The relationship between the child's cogni tive development and neurological maturation has been of theoretical interest for many year s. Due to diff iculties such as the lack of sophisticated techniques for measur ing neurolog ical changes and a paucity of normative data, few studies exist that have attempted to correlate the two factors. Recent theory on intellectual development has proposed that neurological maturation may be a factor in the increase of short-term memory storage space. Improved technology has allowed reliable recordings of neurolog ical maturation.. In an attempt to correlate cogni tive development and neurological maturation, this study tested 3-and II-year old children. Fine motor and gross motor short-term memory tests were used to index cogni tive development. Somatosensory evoked potentials elici ted by median nerve stimulation were used to measure the time required for the sensation to pass along the nerve to specific points on the somatosensory pathway. Times were recorded for N14, N20, and P22 interpeak latencies. Maturation of the central nervous system (brain and spinal cord) and the peripheral nervous system (outside the brain and spinal cord) was indi~ated by the recorded times. Signif icant developmental di fferences occurred between 3-and ll-year-olds in memory levels, per ipheral conduction velocity and central conduction times. Linear regression analyses showed that as age increased, memory levels increased and central conduction times decreased. Between the ll-year-old groups, there were no significant differences in central or peripheral nervous system maturation between subjects who achieved a 12 plus score on the digit span test of the WISC-R and those who scored 7 or lower on the same test. Levels achieved on the experimental gross and fine motor short-term memory tests differed significantly within the ll-year-old group.

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The purpose of this project was to identify in a subject group of engineers and technicians (N = 62) a preferred mode of representation for facilitating correct recall of information from complex graphics. The modes of representation were black and white (b&w) block, b&w icon, color block, and color icon. The researcher's test instrument included twelve complex graphics (six b&w and six color - three per mode). Each graphics presentation was followed by two multiple-choice questions. Recall performance was better using b&w block mode graphics and color icon mode graphics. A standardized test, the Group Embedded Figures Test (GEFT) was used to identify a cognitive style preference (field dependence). Although engineers and technicians in the sample were strongly field-independent, they were not significantly more field-independent than the normative group in the Witkin, Oltman, Raskin, and Karp study (1971). Tests were also employed to look for any significant difference in cognitive style preference due to gender. None was found. Implications from the project results for the design of visuals and their use in technical training are discussed.

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Cognitive control involves the ability to flexibly adjust cognitive processing in order to resist interference and promote goal-directed behaviour. Although frontal cortex is considered to be broadly involved in cognitive control, the mechanisms by which frontal brain areas implement control functions are unclear. Furthermore, aging is associated with reductions in the ability to implement control functions and questions remain as to whether unique cortical responses serve a compensatory role in maintaining maximal performance in later years. Described here are three studies in which electrophysiological data were recorded while participants performed modified versions of the standard Sternberg task. The goal was to determine how top-down control is implemented in younger adults and altered in aging. In study I, the effects of frequent stimulus repetition on the interference-related N450 were investigated in a Sternberg task with a small stimulus set (requiring extensive stimulus resampling) and a task with a large stimulus set (requiring no stimulus resampling).The data indicated that constant stimulus res amp ling required by employing small stimulus sets can undercut the effect of proactive interference on the N450. In study 2, younger and older adults were tested in a standard version of the Sternberg task to determine whether the unique frontal positivity, previously shown to predict memory impairment in older adults during a proactive interference task, would be associated with the improved performance when memory recognition could be aided by unambiguous stimulus familiarity. Here, results indicated that the frontal positivity was associated with poorer memory performance, replicating the effect observed in a more cognitively demanding task, and showing that stimulus familiarity does not mediate compensatory cortical activations in older adults. Although the frontal positivity could be interpreted to reflect maladaptive cortical activation, it may also reflect attempts at compensation that fail to fully ameliorate agerelated decline. Furthermore, the frontal positivity may be the result of older adults' reliance on late occurring, controlled processing in contrast to younger adults' ability to identify stimuli at very early stages of processing. In the final study, working memory load was manipulated in the proactive interference Sternberg task in order to investigate whether the N450 reflects simple interference detection, with little need for cognitive resources, or an active conflict resolution mechanism that requires executive resources to implement. Independent component analysis was used to isolate the effect of interference revealing that the canonical N450 was based on two dissociable cognitive control mechanisms: a left frontal negativity that reflects active interference resolution, , but requires executive resources to implement, and a right frontal negativity that reflects global response inhibition that can be relied on when executive resources are minimal but at the cost of a slowed response. Collectively, these studies advance understanding of the factors that influence younger and older adults' ability to satisfy goal-directed behavioural requirements in the face of interference and the effects of age-related cognitive decline.

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Structures related to ductile siMple shear parallel to the Bankf ield-Tonbill Fault, define a 5km wide zone, the Barton Bay Deformation Zone. Structures present within this zone Include; simple shear fabrics S, C and C , asymmetric Z shaped folds with rotated axes, boudinage and pinch and swell structures and a subhorlzontal extension llneation. The most highly deformed rock is a gabbro mylonite which occurs in the fault zone. The deformation of this gabbro has been traced in stages from a protomylonite to an ultramylonite In which feldspar and chlorite grainslze has been reduced from over 100 microns to as little as 5 microns. Evidence from the mylonite and the surrounding structure indicates that deformation within the Barton Bay Deformation Zone is related to a regional simple shear zone, the Bankf ield-Tombill Fault. Movement along this shear zone was in a south over north oblique strike slip fashion with a dextral sense of displacement.

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Sleep spindles have been found to increase following an intense period of learning on a combination of motor tasks. It is not clear whether these changes are task specific, or a result of learning in general. The current study investigated changes in sleep spindles and spectral power following learning on cognitive procedural (C-PM), simple procedural (S-PM) or declarative (DM) learning tasks. It was hypothesized that S-PM learning would result in increases in Sigma power during Non-REM sleep, whereas C-PM and DM learning would not affect Sigma power. It was also hypothesized that DM learning would increase Theta power during REM sleep, whereas S-PM and C-PM learning would not affect Theta power. Thirty-six participants spent three consecutive nights in the sleep laboratory. Baseline polysomnographic recordings were collected on night 2. Participants were randomly assigned to one of four conditions: C-PM, S-PM, DM or control (C). Memory task training occurred on night 3 followed by polysomnographic recording. Re-testing on respective memory tasks occurred one-week following training. EEG was sampled at 256Hz from 16 sites during sleep. Artifact-free EEG from each sleep stage was submitted to power spectral analysis. The C-PM group made significantly fewer errors, the DM group recalled more, and the S-PM improved on performance from test to re-test. There was a significant night by group interaction for the duration of Stage 2 sleep. Independent t-tests revealed that the S-PM group had significantly more Stage 2 sleep on the test night than the C group. The C-PM and the DM group did not differ from controls in the duration of Stage 2 sleep on test night. There was no significant change in the duration of slow wave sleep (SWS) or REM sleep. Sleep spindle density (spindles/minute) increased significantly from baseline to test night following S-PM learning, but not for C-PM, DM or C groups. This is the first study to have shown that the same pattern of results was found for spindles in SWS. Low Sigma power (12-14Hz) increased significantly during SWS following S-PM learning but not for C-PM, DM or C groups. This effect was maximal at Cz, and the largest increase in Sigma power was at Oz. It was also found that Theta power increased significantly during REM sleep following DM learning, but not for S-PM, C-PM or C groups. This effect was maximal at Cz and the largest change in Theta power was observed at Cz. These findings are consistent with the previous research that simple procedural learning is consolidated during Stage 2 sleep, and provide additional data to suggest that sleep spindles across all non-REM stages and not just Stage 2 sleep may be a mechanism for brain plasticity. This study also provides the first evidence to suggest that Theta activity during REM sleep is involved in memory consolidation.

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Whereas the role of the anterior cingulate cortex (ACC) in cognitive control has received considerable attention, much less work has been done on the role of the ACC in autonomic regulation. Its connections through the vagus nerve to the sinoatrial node of the heart are thought to exert modulatory control over cardiovascular arousal. Therefore, ACC is not only responsible for the implementation of cognitive control, but also for the dynamic regulation of cardiovascular activity that characterizes healthy heart rate and adaptive behaviour. However, cognitive control and autonomic regulation are rarely examined together. Moreover, those studies that have examined the role of phasic vagal cardiac control in conjunction with cognitive performance have produced mixed results, finding relations for specific age groups and types of tasks but not consistently. So, while autonomic regulatory control appears to support effective cognitive performance under some conditions, it is not presently clear just what factors contribute to these relations. The goal of the present study was, therefore, to examine the relations between autonomic arousal, neural responsivity, and cognitive performance in the context of a task that required ACC support. Participants completed a primary inhibitory control task with a working memory load embedded. Pre-test cardiovascular measures were obtained, and ontask ERPs associated with response control (N2/P3) and error-related processes (ERN/Pe) were analyzed. Results indicated that response inhibition was unrelated to phasic vagal cardiac control, as indexed by respiratory sinus arrhythmia (RSA). However, higher resting RSA was associated with larger ERN ampUtude for the highest working memory load condition. This finding suggests that those individuals with greater autonomic regulatory control exhibited more robust ACC error-related responses on the most challenging task condition. On the other hand, exploratory analyses with rate pressure product (RPP), a measure of sympathetic arousal, indicated that higher pre-test RPP (i.e., more sympathetic influence) was associated with more errors on "catch" NoGo trials, i.e., NoGo trials that simultaneously followed other NoGo trials, and consequently, reqviired enhanced response control. Higher pre-test RPP was also associated with smaller amplitude ERNs for all three working memory loads and smaller ampUtude P3s for the low and medium working memory load conditions. Thus, higher pretest sympathetic arousal was associated with poorer performance on more demanding "catch" NoGo trials and less robust ACC-related electrocortical responses. The findings firom the present study highlight tiie interdependence of electrocortical and cardiovascular processes. While higher pre-test parasympathetic control seemed to relate to more robust ACC error-related responses, higher pre-test sympathetic arousal resulted in poorer inhibitory control performance and smaller ACC-generated electrocortical responses. Furthermore, these results provide a base from which to explore the relation between ACC and neuro/cardiac responses in older adults who may display greater variance due to the vulnerabihty of these systems to the normal aging process.

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In this thesis, three main questions were addressed using event-related potentials (ERPs): (1) the timing of lexical semantic access, (2) the influence of "top-down" processes on visual word processing, and (3) the influence of "bottom-up" factors on visual word processing. The timing of lexical semantic access was investigated in two studies using different designs. In Study 1,14 participants completed two tasks: a standard lexical decision (LD) task which required a word/nonword decision to each target stimulus, and a semantically primed version (LS) of it using the same category of words (e.g., animal) within each block following which participants made a category judgment. In Study 2, another 12 participants performed a standard semantic priming task, where target stimulus words (e.g., nurse) could be either semantically related or unrelated to their primes (e.g., doctor, tree) but the order of presentation was randomized. We found evidence in both ERP studies that lexical semantic access might occur early within the first 200 ms (at about 170 ms for Study 1 and at about 160 ms for Study 2). Our results were consistent with more recent ERP and eye-tracking studies and are in contrast with the traditional research focus on the N400 component. "Top-down" processes, such as a person's expectation and strategic decisions, were possible in Study 1 because of the blocked design, but they were not for Study 2 with a randomized design. Comparing results from two studies, we found that visual word processing could be affected by a person's expectation and the effect occurred early at a sensory/perceptual stage: a semantic task effect in the PI component at about 100 ms in the ERP was found in Study 1 , but not in Study 2. Furthermore, we found that such "top-down" influence on visual word processing might be mediated through separate mechanisms depending on whether the stimulus was a word or a nonword. "Bottom-up" factors involve inherent characteristics of particular words, such as bigram frequency (the total frequency of two-letter combinations of a word), word frequency (the frequency of the written form of a word), and neighborhood density (the number of words that can be generated by changing one letter of an original word or nonword). A bigram frequency effect was found when comparing the results from Studies 1 and 2, but it was examined more closely in Study 3. Fourteen participants performed a similar standard lexical decision task but the words and nonwords were selected systematically to provide a greater range in the aforementioned factors. As a result, a total of 18 word conditions were created with 18 nonword conditions matched on neighborhood density and neighborhood frequency. Using multiple regression analyses, we foimd that the PI amplitude was significantly related to bigram frequency for both words and nonwords, consistent with results from Studies 1 and 2. In addition, word frequency and neighborhood frequency were also able to influence the PI amplitude separately for words and for nonwords and there appeared to be a spatial dissociation between the two effects: for words, the word frequency effect in PI was found at the left electrode site; for nonwords, the neighborhood frequency effect in PI was fovind at the right elecfrode site. The implications of otir findings are discussed.

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years 8 months) and 24 older (M == 7 years 4 months) children. A Monitoring Process Model (MPM) was developed and tested in order to ascertain at which component process ofthe MPM age differences would emerge. The MPM had four components: (1) assessment; (2) evaluation; (3) planning; and (4) behavioural control. The MPM was assessed directly using a referential communication task in which the children were asked to make a series of five Lego buildings (a baseline condition and one building for each MPM component). Children listened to instructions from one experimenter while a second experimenter in the room (a confederate) intetjected varying levels ofverbal feedback in order to assist the children and control the component ofthe MPM. This design allowed us to determine at which "stage" ofprocessing children would most likely have difficulty monitoring themselves in this social-cognitive task. Developmental differences were obselVed for the evaluation, planning and behavioural control components suggesting that older children were able to be more successful with the more explicit metacomponents. Interestingly, however, there was no age difference in terms ofLego task success in the baseline condition suggesting that without the intelVention ofthe confederate younger children monitored the task about as well as older children. This pattern ofresults indicates that the younger children were disrupted by the feedback rather than helped. On the other hand, the older children were able to incorporate the feedback offered by the confederate into a plan ofaction. Another aim ofthis study was to assess similar processing components to those investigated by the MPM Lego task in a more naturalistic observation. Together the use ofthe Lego Task ( a social cognitive task) and the naturalistic social interaction allowed for the appraisal of cross-domain continuities and discontinuities in monitoring behaviours. In this vein, analyses were undertaken in order to ascertain whether or not successful performance in the MPM Lego Task would predict cross-domain competence in the more naturalistic social interchange. Indeed, success in the two latter components ofthe MPM (planning and behavioural control) was related to overall competence in the naturalistic task. However, this cross-domain prediction was not evident for all levels ofthe naturalistic interchange suggesting that the nature ofthe feedback a child receives is an important determinant ofresponse competency. Individual difference measures reflecting the children's general cognitive capacity (Working Memory and Digit Span) and verbal ability (vocabulary) were also taken in an effort to account for more variance in the prediction oftask success. However, these individual difference measures did not serve to enhance the prediction oftask performance in either the Lego Task or the naturalistic task. Similarly, parental responses to questionnaires pertaining to their child's temperament and social experience also failed to increase prediction oftask performance. On-line measures ofthe children's engagement, positive affect and anxiety also failed to predict competence ratings.

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Nuclear magnetic resonance spectroscopy has been used to study donor-acceptor complexes of boron trifluoride with several ureas, tetramethylthiourea, tetramethylselenourea, and tetramethylquanidine as well as adducts of tetramethyl- -urea with BF2Cl, BFC1 2 , and BC1 3 - A large number of mixed tetrahaloborate ions, including some of the ternary ones such as BF2CIBr-,have been obtained by ligand exchange reactions and studied by NMR techniques. The bonding in these ions is of the same inherent interest as the bonding in the isoelectronic tetrahalomethanes which have been the subject of many detailed studies and have been involved in a controversy concerning the existence of and the nature of "fluorine hyperconjugation" or C-F P1T- Pn bonding_ Ligand exchange reactions also gave rise to the difluoroboron cation, (TMU)20BF2+o The difluoroboron cation has been observed in solutions of TMU-BF3 , and has been proposed as a possible intermediate for fluorine exchange reactions in BF3 adducts.

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Daytime napping improves well-being and performance for young adults. The benefits of napping in older adults should be investigated because they have fragmented nocturnal sleep, cognitive declines, and more opportunity to nap. In addition, experience with napping might influence the benefits of napping. Study 1 examined the role of experience with napping in young adults. Habitual (n = 23) and non-habitual nappers (n = 16) were randomly assigned to a 20-minute nap or a 20- minute reading condition. Both groups slept the same according to macro architecture. However, microarchitecture showed greater theta, alpha, and beta power during Stage 1, and greater delta, alpha, and sigma power during Stage 2 for habitual nappers, for the most part indicating better sleep. Both groups felt less sleepy after the nap. P2 latency, reflecting information processing, decreased after the nap for habitual nappers, and after the control condition for non-habitual nappers. In sum, both groups who slept felt better, but only the habitual nappers who napped gained a benefit in terms of information processing. Based on this outcome, experience with napping was investigated in Study 2. Study 2 examined the extent to which daytime napping enhanced cognition in older adults, especially frontal lobe function. Cognitive deficits in older adults may be due to sleep loss and age-related decline in brain functioning. Longer naps were expected to provide greater improvement, particularly for older adults, by reducing sleep pressure. Thirty-two adults, aged 24-70 years, participated in a repeated measures dose-response manipulation of sleep pressure. Twenty- and sixty-minute naps were compared to a no-nap condition in three age groups. Mood, subjective sleepiness, reaction time, working memory, 11 novelty detection, and waking electro physiological measures were taken before and after each condition. EEG was also recorded during each nap or rest condition. Napping reduced subjective sleepiness, improved working memory (serial addition / subtraction task), and improved attention (reduced P2 amplitude). Physiological sleepiness (i.e., waking theta power) increased following the control condition, and decreased after the longer nap. Increased beta power after the short nap, and seen with older adults overall, may have reflected increased mental effort. Older adults had longer latencies and smaller amplitudes for several event-related potential components, and higher beta and gamma power. Following the longer nap, gamma power decreased for older adults, but increased for young adults. Beta and gamma power may represent enhanced alertness or mental effort. In addition, Nl amplitude showed that benefits depend on the preceding nap length as well as age. Since the middle group had smaller Nl amplitudes following the short nap and rest condition, it is possible that they needed a longer nap to maintain alertness. Older adults did not show improvements to Nl amplitude following any condition; they may have needed a nap longer than 60 minutes to gain benefits to attention or early information processing. Sleep characteristics were not related to benefits of napping. Experience with napping was also investigated. Subjective data confirmed habitual nappers were happier to nap, while non-habitual nappers were happier to stay awake, reflecting self-identified napping habits. Non-habitual nappers were sleepier after a nap, and had faster brain activity (i.e., heightened vigilance) at sleep onset. These reasons may explain why non-habitual nappers choose not to nap.

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Children with High-Functioning Autism (HF A) are more vulnerable to developing Obsessive Compulsive Disorder (OCD) than typically developing children and those with Low-Functioning Autism (Gadow et al., 2005). This study used a multiple baseline design across behaviours (Cooper, Heron, & Heward, 2007) to investigate if a two phase function-based Cognitive Behaviour Therapy (CBT) would decrease obsessive compulsive behaviours (OCBs) in two children ages 7 and 9 who met criteria for OCD and HF A. This multimodal treatment package consisted of treatment enhancements to meet the children's cognitive, linguistic, and social challenges associated with their HF A diagnosis, as well as a manual and accompanied children's workbook (Vause, Neil, & Feldman, in progress). In line with previous research conducted on CBT as a treatment for OCD in this population (e.g., Wood et at, 2009), the children in this study experienced clinically significant decreases in their OCBs as a result of receiving the CBT protocol.

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Dehumanizing ideologies that explicitly liken other humans to “inferior” animals can have negative consequences for intergroup attitudes and relations. Surprisingly, very little is known about the causes of dehumanization, and essentially no research has examined strategies for reducing dehumanizing tendencies. The Interspecies Model of Prejudice specifies that animalistic dehumanization may be rooted in basic hierarchical beliefs regarding human superiority over animals. This theoretical reasoning suggests that narrowing the human-animal divide should also reduce dehumanization. The purpose of the present dissertation, therefore, was to gain a more complete understanding of the predictors of and solutions to dehumanization by examining the Interspecies Model of Prejudice, first from a layperson’s perspective and then among young children. In Study 1, laypeople strongly rejected the human-animal divide as a probable cause of, or solution to, dehumanization, despite evidence that their own personal beliefs in the human-animal divide positively predicted their dehumanization (and prejudice) scores. From Study 1, it was concluded that the human-animal divide, despite being a robust empirical predictor of dehumanization, is largely unrecognized as a probable cause of, or solution to, dehumanization by non-experts in the psychology of prejudice. Studies 2 and 3 explored the expression of dehumanization, as well as the Interspecies Model of Prejudice, among children ages six to ten years (Studies 2 and 3) and parents (Study 3). Across both studies, White children showed evidence of racial dehumanization by attributing a Black child target fewer “uniquely human” characteristics than the White child target, representing the first systematic evidence of racial dehumanization among children. In Study 3, path analyses supported the Interspecies Model of Prejudice among children. Specifically, children’s beliefs in the human-animal divide predicted greater racial prejudice, an effect explained by heightened racial dehumanization. Moreover, parents’ Social Dominance Orientation (preference for social hierarchy and inequality) positively predicted children’s human-animal divide beliefs. Critically, these effects remained significant even after controlling for established predictors of child-prejudice (i.e., parent prejudice, authoritarian parenting, and social-cognitive skills) and relevant child demographics (i.e., age and sex). Similar patterns emerged among parent participants, further supporting the Interspecies Model of Prejudice. Encouragingly, children reported narrower human-animal divide perceptions after being exposed to an experimental prime (versus control) that highlighted the similarities among humans and animals. Together the three studies reported in this dissertation offer important and novel contributions to the dehumanization and prejudice literature. Not only did we find the first systematic evidence of racial dehumanization among children, we established the human-animal divide as a meaningful dehumanization precursor. Moreover, empirical support was obtained for the Interspecies Model of Prejudice among diverse samples including university students (Study 1), children (Studies 2 and 3), and adult-aged samples (Study 3). Importantly, each study also highlights the promising social implication of targeting the human-animal divide in interventions to reduce dehumanization and other prejudicial processes.