Food quantity discrimination in puppies (Canis lupus familiaris)

Animal Cognition - There is considerable evidence that animals are able to discriminate between quantities. Despite the fact that quantitative skills have been extensively studied in adult...     

A model to study orienting responses in zebrafish,and applications towards the emotion–cognition interaction

Animal Cognition - Orienting responses (ORs) are whole-organism reflexes that are elicited by innocuous stimuli, and which decrease in magnitude after stimulus repetition. ORs represent relatively...     

Spatial representation of pitch height: the SMARC effect

Through the preferential pairing of response positions to pitch, here we show that the internal representation of pitch height is spatial in nature and affects performance, especially in musically trained participants, when response alternatives are either vertically or horizontally aligned. The finding that our cognitive system maps pitch height onto an internal representation of space, which in turn affects motor performance even when this perceptual attribute is irrelevant to the task, extends previous studies on auditory perception and suggests an interesting analogy between music perception and mathematical cognition. Both the basic elements of mathematical cognition (i.e. numbers) and the basic elements of musical cognition (i.e. pitches), appear to be mapped onto a mental spatial representation in a way that affects motor performance.     

Acculturation, parent-adolescent conflict, and adolescent adjustment in Mexican American families

We tested an acculturation model in a community sample of Mexican American families (146 mothers, 137 fathers, and 146 adolescents) that proposed that differences between parents and adolescents in acculturation would be associated with parent-adolescent conflict and adolescent adjustment problems. Contrary to hypotheses, we found that families who exhibited an acculturation gap were not more likely to report parent-adolescent conflict or adolescent adjustment problems. In fact, familial conflict and adolescent sexual experience were associated with high levels of acculturation among adolescents and their parents. Pending replication, these findings suggest that both parent and children acculturation may independently predict familial processes and youth outcomes, irrespective of an acculturation gap. Future research should consider other factors aside from acculturation differences that might account for parent-adolescent conflict and adolescent adjustment in Mexican American families.     

The effect of visual word features on the acquisition of orthographic knowledge

Research with adults has shown that the distortion of visual word features, and in particular of the multiletter features within words, hampers word recognition. In this study, "CaSe MiXiNg" was employed to examine the effect of disrupting visual word features on the acquisition of orthographic knowledge in children. During the training, 18 beginning and 27 advanced readers (in Grades 2, 4, and 5) repeatedly read a set of pseudowords in either lowercase or mixed case. During this training, case mixing appeared to impair reading speed in both reader groups. At posttest, 1 day after the training, case format was either the same as or different from that during the training. Lowercase pseudowords were recognized faster after a lowercase training than after a mixed-case training. In a second study, case was found not to affect the rapid naming of single letters. The combined results suggest that case mixing disrupted the multiletter features in pseudowords and that the disruption of these features can affect the acquisition of orthographic knowledge.     

Neuromuscular-skeletal origins of predominant patterns of coordination in rhythmic two-joint arm movement

The authors tested for predominant patterns of coordination in the combination of rhythmic flexion-extension (FE) and supination- (SP) at the elbow-joint complex. Participants (N=10) spontaneously established in-phase (supination synchronized with flexion) and antiphase (pronation synchronized with flexion) patterns. In addition, the authors used a motorized robot arm to generate involuntary SP movements with different phase relations with respect to voluntary FE. The involuntarily induced in-phase pattern was accentuated and was more consistent than other patterns. The result provides evidence that the predominance of the in-phase pattern originates in the influence of neuromuscular-skeletal constraints rather than in a preference dictated by perceptual-cognitive factors implicated in voluntary control. Neuromuscular-skeletal constraints involved in the predominance of the in-phase and the antiphase patterns are discussed.     

The role of overt head movement and attention in persuasion

This study examined the effect of overt head movement on attitudes toward a product. In a headphones test, participants were required to listen to music and to either nod or shake their heads. Some participants listened to a CD of music; other participants listened to a CD of the same music and a persuasive message about the headphones. Overt head movement affected participants' product choice and price perception when they were presented with the music and a persuasive message. The findings are interpreted to suggest that head movement can be instrumental in participants' product evaluation if the head movement is directed or focused on the attitude object.     

The influence of prior choices on current choice

Three pigeons chose between random-interval (RI) and tandem, continuous-reinforcement, fixed-interval (crf-FI) reinforcement schedules by pecking either of two keys. As long as a pigeon pecked on the RI key, both keys remained available. If a pigeon pecked on the crf-FI key, then the RI key became unavailable and the crf-FI timer began to time out. With this procedure, once the RI key was initially pecked, the prospective value of both alternatives remained constant regardless of time spent pecking on the RI key without reinforcement (RI waiting time). Despite this constancy, the rate at which pigeons switched from the RI to the crf-FI decreased sharply as RI waiting time increased. That is, prior choices influenced current choice-an exercise effect. It is argued that such influence (independent of reinforcement contingencies) may serve as a sunk-cost commitment device in self-control situations. In a second experiment, extinction was programmed if RI waiting time exceeded a certain value. Rate of switching to the crf-FI first decreased and then increased as the extinction point approached, showing sensitivity to both prior choices and reinforcement contingencies. In a third experiment, crf-FI availability was limited to a brief window during the RI waiting time. When constrained in this way, switching occurred at a high rate regardless of when, during the RI waiting time, the crf-FI became available.