Responses of sexually experienced and naive male rats to cues from receptive vs. nonreceptive females

In order to learn more about their reaction to the female sex attractant, 61 male Norway rats were given two-choice preference tests in which they reacted to cues from receptive vs. non-receptive females. In the first experiment, 16 heterosexually experienced males showed a reliable preference (p < .01) for receptive over nonreceptive anesthetized females, as did 15 naive males (p < .02) which later proved to be copulators. Ten naive males which later proved to be noncopulators showed no reliable preference for either type of female. In the second experiment, 15 naive males which later proved to be copulators showed no reliable preference for the odors from receptive vs. nonreceptive females. From these experiments, we conclude that naive males which later prove to be sexually vigorous are attracted to the composite bodily cues from receptive females, and that this attraction is not mediated by olfactory cues alone.     

Children's memory for orientation in the absence of external cues

Some have interpreted children's reliance on external visual cues as evidence that they are unable to use internal cues for orientation. This hypothesis was examined in experiment 1, where 24 preschoolers were tested on left-right, vertical-horizontal, and mirror-image oblique discriminations under essentially context-free conditions. Subjects succeeded on all discrimination problems and performed equally well on vertical-horizontal and mirror-image oblique discriminations. Thus, preschoolers can use an internal frame of reference to code orientation. Experiment 2 contrasted children's performance under context-free conditions with their ability to discriminate orientation in the presence of external visual cues. Children who had discriminated left-right oblique and nonoblique mirror-image forms in experiment 1 failed to so discriminate in experiment 2. This result is discussed in terms of a breakdown in the ability to use internal cues when external visual cues are available.     

Children's understanding of emotion in speech

Children's understanding of emotion in speech was explored in three experiments. In Experiment 1, 4- to 10-year-old children and adults (N = 165) judged the happiness or sadness of the speaker from cues conveyed by propositional content and affective paralanguage. When the cues conflicted (i.e., a happy situation was described with sad paralanguage), children relied primarily on content, in contrast to adults, who relied on paralanguage. There were gradual developmental changes from 4-year-olds' almost exclusive focus on content to adults' exclusive focus on paralanguage. Children of all ages exhibited greater response latencies to utterances with conflicting cues than to those with nonconflicting cues, indicating that they processed both sources of emotional information. Children accurately labeled the affective paralanguage when the propositional cues to emotion were obscured by a foreign language (Experiment 2, N = 20) or by low-pass filtering (Experiment 3, N = 60). The findings are consistent with children's limited understanding of the communicative functions of affective paralanguage.     

The effect of narrative cues on infants' imitation from television and picture books

Infants can imitate a novel action sequence from television and picture books, yet there has been no direct comparison of infants' imitation from the 2 types of media. Varying the narrative cues available during the demonstration and test, the current experiments measured 18- and 24-month-olds' imitation from television and picture books. Infants imitated from both media types when full narrative cues (Experiment 1; N = 76) or empty, meaningless narration (Experiment 2; N = 135) accompanied the demonstrations, but they imitated more from television than books. In Experiment 3 (N = 27), infants imitated from a book based on narration alone, without the presence of pictures. These results are discussed in relation to age-related changes in cognitive flexibility and infants' emerging symbolic understanding.     

The cues that infants use to distinguish discontinuous quantities: evidence using a shift-rate recovery paradigm

A novel experimental method, shift-rate recovery, was developed and used in a series of three experiments. These examined the extent to which 6-month-old infants (N = 131) find perceptual cues such as density and length useful in the discrimination of linearly arranged sets containing large numbers of objects. Results showed that infants discriminated between arrays that differ in number and density, with length held constant, when the arrays were presented either simultaneously or successively. On the other hand, infants discriminated only between arrays that differ in number and length, with density held constant, when the arrays were presented simultaneously. Infants were, however, able to perform a successive length discrimination when the arrays were continuous rather than consisting of discrete items. These findings support the conclusion that infants are able to discriminate between large number sets by relying on absolute cues such as density (but not length) and on relative cues such as optical one-to-one correspondence.     

Epistemic states and traits: preschoolers appreciate the differential informativeness of situation-specific and person-specific cues to knowledge

Previous research has demonstrated that preschoolers can use situation-specific (e.g., visual access) and person-specific (e.g., prior accuracy) cues to infer what others know. The present studies investigated whether 4- and 5-year-olds appreciate the differential informativeness of these types of cues. In Experiment 1 (N = 50), children used others' prior labeling accuracy as a cue when learning labels for, but not the visual identity of, hidden objects. In Experiment 2 (N = 64), with both cues present, children attended more to visual access than prior accuracy when learning the visual identity of, but not labels for, hidden objects. These findings demonstrate that children appreciate the difference between situation- and person-specific cues and flexibly evaluate these cues depending on what information they are seeking.     

Odors of individuality originating from the major histocompatibility complex are masked by diet cues in the urine of rats

Male Long-Evans rats were trained to discriminate between the urine odors of two congenic strains of rats (PVG and PVG.R1) in an olfactometer on a go/no-go operant task with water reinforcement. These odor donors differ genetically at only one locus of the major histocompatibility complex (MHC). The ability of the subjects to transfer their training to discriminate between novel individuals of the same MHC strain on the same and different diets was then examined. The subjects correctly generalized their original training to new samples from previously undiscriminated individuals of the same MHC type on the same diet without a significant drop in performance. A change in diet disrupted the perception of the MHC-related odor. In a second experiment, rats were trained to discriminate between the odors of pairs of genetically identical PVG or PVG.R1 rats on different diets and were tested for generalization using the odors of rats of the other strain (PVG.R1 or PVG) maintained on the same diet. Changing the strain of the odor donor did not disrupt the learned discrimination. The results of these two experiments confirm the ability of the MHC to generate constant cues in the urine but also reveal that variable diet cues disrupt the perception of these cues. The relationship between the MHC, diet, and other factors in determining individual odors is discussed.     

Mechanism-based causal reasoning in young children

The hypothesis that children develop an understanding of causal mechanisms was tested across 3 experiments. In Experiment 1 (N = 48), preschoolers had to choose as efficacious either a cause that had worked in the past, but was now disconnected from its effect, or a cause that had failed to work previously, but was now connected. Four-year-olds chose the now-connected cause more often than 3-year-olds. Experiment 2 (N = 16) showed 4-year-olds responded appropriately to an irrelevant modification in the same causal system. Experiment 3 (N = 24) demonstrated when the mechanism was batteries rather than connection, 3-year-olds could properly distinguish between relevant and irrelevant modifications. Together, these data suggest that understanding of specific causal mechanisms develops at different ages.     

A developmental analysis of early time concepts: the equivalence and additivity of the effect of interfering cues on duration comparisons of young children

Young children compare durations correctly and explain their conclusions logically only when no interfering cues such as distance and speed are introduced. We investigated whether type of cue and additivity of interfering cues affect children's duration comparisons. 4- and 5-year-old children were asked to compare the burning times of pairs of partially synchronous lights differing in intensity, bulb size, or both. Those who erred tended to attribute longer duration to the brighter or larger bulb, brightness having a stronger interfering effect than size. Since brightness might qualify as "work" more than bulb size might, the finding that the former interferes more than the latter supports Piaget's basic claim of children's confusion of time with "work." The fact that bulb size interferes at all, which does not fit into Piaget's framework, may be explained in terms of children's inability to distinguish clearly between time-related and time-unrelated cues and their assumption of direct relations between dimensions. Additivity of interference did not emerge, indicating that the previous finding which suggested its existence--distance plus speed interfering with duration comparisons more than speed alone--should be reassessed in terms of type of interfering cues, that is, distance interferes more than speed with time.     

Revaluation of geometric cues reduces landmark discrimination via within-compound associations

Rats were trained in a triangular water maze in which a compound of geometric and landmark cues indicated the position of a submerged platform. Rats that then underwent revaluation of the geometric cues in the absence of the landmarks subsequently failed to discriminate between the landmarks. In contrast, those animals that received geometry training consistent with their previous experience of the geometry–landmark compound continued to discriminate the landmark cues. The experiment showed that within-compound associations had formed between the geometry and landmarks, and that representations of absent geometric cues could be evoked via presentation of the landmark cues alone. We argue that these evoked representations of the absent geometry cues can counteract any overshadowing of the landmark by geometry cues, and may sometimes result in potentiation. The results of this study do not support theories of cue-competition failure based on independent cue processing, but remain readily explicable by appeal to an account based on within-compound associations.     

Sequential pattern learning and its associations with inattentive and hyperactive concerns in college students

College students frequently experience inattentive and hyperactive concerns. In multiple independent samples and three randomised experiments, we examined multiple versions of a short performance‐based measure translated from basic research on how organisms learn sequential stimuli patterns when such patterns are interleaved with information that is irrelevant to the pattern being learned. In one experiment, performance was uniquely related to self‐reported inattentive and hyperactive concerns, taking into account performance on a widely used inhibitory control task (Study 1, n = 20). In the two other experiments, randomly assigned variants of this measure demonstrated that: (a) relations among performance and inattentive and hyperactive concerns could be identified regardless of irrelevant stimuli positioning (Study 2, n = 60), and (b) one could reverse the relation between performance and inattentive and hyperactive concerns by visually enhancing distinguishing features of irrelevant stimuli (Study 3, n = 20). The findings have significant implications for multi‐method assessments of inattentive and hyperactive concerns in college settings.     

Hearing Where the Eyes See: Children Use an Irrelevant Visual Cue When Localizing Sounds

To reduce sensory uncertainty, humans combine cues from multiple senses. However, in everyday life, many co‐occurring cues are irrelevant to the task at hand. How do humans know which cues to ignore? And does this ability change with development? This study shows the ability to ignore cross‐modal irrelevant information develops late in childhood. Participants performed a sound discrimination task, with or without an irrelevant visual flash, presented synchronously in front of them. Adults ignored the irrelevant visual information, while 7‐ to 10‐year‐olds' responses were biased toward the flash location. The findings show that acquiring mature cue combination mechanisms is a multifaceted process that includes learning to ignore irrelevant cues, as well as to optimally combine relevant cues.     

Domesticated dogs (<Emphasis Type="Italic">Canis familiaris</Emphasis>) tend to follow repeated deceptive human cues even when food is visible

There is abundant evidence that domestic dogs (Canis familiaris) readily follow pointing and other cues given by humans. But there has been much less research into the question of whether dogs can learn to discriminate between different humans giving repeated honest or dishonest cues as to food location, by ignoring the information imparted by the deceiver. Prior research has demonstrated that even after repeated exposures to deceptive cues with respect to food location, dogs failed to learn to ignore those cues completely. Kundey, De Los Reyes, Arbuthnot, Coshun, Molina, and Royer (2010) found the same outcome in a similar experiment. The purpose of the current experiment was to determine if dogs could learn to discriminate between an honest and a deceptive human by ignoring the deceiver’s cues even when it was obvious that the container being pointed at was not baited by using two transparent containers. Eight dogs were tested. On 20 cooperator trials, the experimenter stood behind the baited container and cued the dog, located midway between the containers and 3 m away, to approach it. On 20 deceiver trials, a different experimenter stood behind the empty container and cued the dog to approach that container. Results replicated prior research in that, even though the containers were transparent, the dogs failed to learn to distrust the deceiver completely and went to the empty and indicated container on more than half of the deceiver trials.     

Effect of early experience and age on initial responsiveness ofTilapia mossambica fry to a maternal model

Fry of the maternal mouth brooding fishTilapia mossambica were tested for the effects of (1) rearing and (2) increasing age on initial responsiveness to a gray disk covered with small black pits that served as a maternal model. In the first experiment, the eggs were removed from their mother’s mouth shortly after spawning, hatched, and the fry raised in groups, singly in complete visual isolation, or by the mother (control) until testing. When free swimming, the fry were tested individually for responsiveness to the model. High levels of responsiveness were exhibited by all fry regardless of rearing experience, indicating that responsiveness to the mother’s mouth is fully developed at birth and needs no previous social experience for its expression. In the second experiment, naive group-reared fry were tested individually for initial responsiveness to the model at 13, 16, 20, or 26 days postspawning. It was found that naive fry were strongly attracted to the model at 13 and 16 days of age but were neutral or actively avoiding it at 26 days of age. This decline is almost identical to the decline in responsiveness of normally reared fry toward their actual mother.     

Infants make quantity discriminations for substances

Infants can track small groups of solid objects, and infants can respond when these quantities change. But earlier work is equivocal about whether infants can track continuous substances, such as piles of sand. Experiment 1 (N = 88) used a habituation paradigm to show infants can register changes in the size of piles of sand that they see poured from a container when there is a 1-to-4 ratio. Experiment 2 (N = 82) tested whether infants could discriminate a 1-to-2 ratio. The results demonstrate that females could discriminate the difference but males could not. These findings constitute the youngest evidence of successful quantity discriminations for a noncohesive substance and begin to characterize the nature of the representation for noncohesive entities.     

Preschool children use linguistic form class and pragmatic cues to interpret generics

Generic noun phrases (e.g., "Bats live in caves") are important for expressing knowledge about abstract kinds. Past work has found that parents frequently use generic noun phrases in their speech to young children. However, little is known regarding how children understand these expressions, nor which cues signal generic meaning. The present set of 5 studies examined the influence of linguistic form class (e.g., "What color are dogs?" [generic] versus "What color are the dogs?" [nongeneric]) and of pragmatic context (e.g., "What color are they?" in the presence of either a single exemplar [generic] or multiple exemplars [nongeneric]). Participants were 2-year-olds (N = 42), 3-year-olds (N = 40), 4-year-olds (N = 40), and adults (N = 51). The data indicate that by 2 years of age, children use linguistic form class, and by 3 years of age, children use pragmatic context. These findings demonstrate that young children have begun to understand the distinction between generic and nongeneric noun phrases from a very young age, and that identification of generics is signaled not by formal or pragmatic cues alone, but by a combination of information from both language form and pragmatic context. It is suggested that children make use of multiple linguistic and conceptual cues to acquire and interpret generics.     

Overshadowing of geometric cues by a beacon in a spatial navigation task

In three experiments, we examined whether overshadowing of geometric cues by a discrete landmark (beacon) is due to the relative saliences of the cues. Using a virtual water maze task, human participants were required to locate a platform marked by a beacon in a distinctively shaped pool. In Experiment 1, the beacon overshadowed geometric cues in a trapezium, but not in an isosceles triangle. The longer escape latencies during acquisition in the trapezium control group with no beacon suggest that the geometric cues in the trapezium were less salient than those in the triangle. In Experiment 2, we evaluated whether generalization decrement, caused by the removal of the beacon at test, could account for overshadowing. An additional beacon was placed in an alternative corner. For the control groups, the beacons were identical; for the overshadow groups, they were visually unique. Overshadowing was again found in the trapezium. In Experiment 3, we tested whether the absence of overshadowing in the triangle was due to the geometric cues being more salient than the beacon. Following training, the beacon was relocated to a different corner. Participants approached the beacon rather than the trained platform corner, suggesting that the beacon was more salient. These results suggest that associative processes do not fully explain cue competition in the spatial domain.     

Evidence for referential understanding in the emotions domain at twelve and eighteen months

Infants as young as 12 months readily modulate their behavior toward novel, ambiguous objects based on emotional responses that others display. Such social-referencing skill offers powerful benefits to infants' knowledge acquisition, but the magnitude of these benefits depends on whether they appreciate the referential quality of others' emotional messages, and are skilled at using cues to reference (e.g., gaze direction, body posture) to guide their interpretation of such messages. Two studies demonstrated referential understanding in 12- and 18-month-olds' responses to another's emotional outburst. Infants relied on the presence versus absence of referential cues to determine whether an emotional message should be linked with a salient, novel object in the first study (N = 48), and they actively consulted referential cues to disambiguate the intended target of an affective display in the second study (N = 32). These findings provide the first experimental evidence of such sophisticated referential abilities in 12-month-olds, as well as the first evidence that infant social referencing at any age actually trades on referential understanding.     

Forming chunks in instrumental learning: The role of overshadowing

Lower order units combined into higher order functional units (e.g., letters into words) are calledchunks. The hypothesis tested here suggests that chunks are formed when memories of goal events signal other goal events, a signal capacity that can be reduced when memories are seriously overshadowed by other more valid cues calledgrouping cues. In support of this hypothesis, it was found, in each of three experiments employing rats in runways, that the capacity of the memory of nonreward to signal reward depended on its validity relative to that of two other situational cues, runway brightness cues and a change in brightness cues, from one trial to the next. Specifically, the capacity of the memory of nonreward to signal reward was much more seriously reduced when it was in competition with more valid situational cues (.33 vs. 1.00, Experiment 1; .50 vs. 1.00, Experiment 2) than when it was in competition with situational cues having either the same validity (.33, Experiment 1) or a slightly higher validity (.33 vs. .50, Experiment 3). It was also found that grouping each of two series was less effective in producing chunking than was grouping only one of the series.     

Comparison of Training Devices for Teaching Emotional Discrimination

This study compared two training methods for preparing counselors to discriminate verbal, facial, and voice cues that are associated with the emotion of depression. One hundred and fourteen upperclass students were randomly assigned to one of three treatments: (a) programmed text, (b) video presentation, or (c) control (no training). All subjects then responded to a videotape criterion measure compiled from actual counseling sessions. Three completely randomized, single classification analysis of variance designs were employed to analyze the data. Results showed programmed text treatment to be more effective in teaching discrimination of depressive cues than the video presentation. Implications for counselor education and suggestions for further research are given.