Children's numerical skill and judgments of confidence in estimation

This study investigated how children's fluent use of a basic numerical skill is related to their perceptions of confidence on a task of quantitative estimation. One hundred four 10th graders (age 15.7 years) were categorized according to level of numerical fluency as assessed by timed tasks of counting in various nonunity increments. They then made estimates of large numbers of dots and rated how confident they were on each trial. The estimation task varied according to two within-subject factors of task difficulty. It was found that counting skill was related not only to accuracy in estimating, but also to the appropriateness of the children's confidence in their responses. Skillful children made judgments that corresponded with actual task difficulty. A derived calibration score corroborated ANOVA findings of the interaction of skill level and task difficulty on confidence ratings. It also revealed that while girls were less confident than boys, they were actually more realistic in their judgments. Findings are discussed in terms of (a) the effect of stimulus knowledge on awareness of task difficulty and (b) sex differences in achievement-related expectancies.     

Short-term memory for time in children and adults: A behavioral study and a model

This experiment investigated the effect of the short-term retention of duration on temporal discrimination in 5- and 8-year-olds, as well as in adults, by using an episodic temporal generalization task. In each age group, the participants' task was to compare two successive durations (a standard and a comparison duration) separated by a retention interval of 500ms, 5s, or 10s, with the order of presentation of these two durations being counterbalanced. The results revealed a shortening effect for the first presented stimulus in all of the age groups, although this was greater in the younger children, thereby indicating the presence of a negative time-order error. Furthermore, introducing a retention delay between the two durations did not produce a shortening effect but instead flattened the generalization gradient, especially in the younger children. However, this flattening of the generalization gradient with the retention delay was more marked between 500ms and 5s than between 5s and 10s. Thus, retaining the first duration in short-term memory during a task requiring the comparison of two successive durations reduced temporal discrimination accuracy and did so to a greater extent in the younger children.     

Latent inhibition: The effects of ITI and CS intensity during preexposure

Two experiments are reported which test the effects of intertrial interval (ITI) and stimulus intensity during nonreinforced preexposure in the latent inhibition paradigm. In Experiment 1, using mice in an escape-avoidance task, latent inhibition was a direct function of the duration of stimulus intertrial interval during preexposure. In Experiment 2, using rats in a CER task, latent inhibition was a direct function of stimulus intensity during preexposure. These findings are discussed in terms of equivalent effects which have been reported in the habituation paradigm.     

The development of communication: Attribute variation leads to contrast failure

Groups of 5-year-olds in two experiments described multidimensional triangles for a listener. The attribute differentiating referent triangles from nonreferent triangles in Experiment I was constant across trials for the simple condition group, while any one of three attributes was distinctive on a given trial for the complex condition group. One-adjective messages by subjects in the simple condition were virtually always informative; in the complex group, such messages were predominantly ambiguous. The boundaries of the variation effect were assessed in Experiment II. In addition to the simple-complex variation of the relevant attributes, the values of the irrelevant attributes either varied across trials in the diverse groups or remained constant in the constant groups. One-adjective messages were informative only in the simple-constant group; in the other groups, such messages were predominantly ambiguous. Thus, young children can base their communications on a comparative analysis of stimulus arrays, but performance deteriorates when there is any variation in relevant or irrelevant attributes. These results were discussed in relation to various theories of the development of meaning and communication: the cognitive overload theory, the broad context theory, and the perceptual saliency theory.     

Reminder-induced recovery from blocking as a function of the number of compound trials

Conditioned lick suppression in rats was employed to examine changes in the associative status of a blocked stimulus as a function of the number of compound stimulus conditioning trials. In each of two experiments, prior tone-footshock pairings produced similar blocking of conditioned responding to the light element of a tone-light compound when either two or six compound trials were used. In experiment 1, two exposures to the light alone in a dissimilar context during the retention interval, i.e., a reminder treatment, resulted in a restoration of responding to the light which was complete and similar for animals receiving two or six compound trials. This indicated that latent acquisition with respect to the blocked stimulus was largely complete after two compound trials. Because of a potential ceiling effect for reminder-induced recovery from blocking, Experiment 2 employed an attenuated reminder (one light exposure). This reminder reversed the blocking when six, but not when two, compound trials were used. These results suggest that, after latent acquisition to the blocked stimulus is complete, the blocked stimulus continues to be processed during additional compound stimulus conditioning trials, with a consequent latent facilitation of retrieval of associations to the blocked stimulus.     

The long-term retention of time: A developmental study

Two experiments investigated the age-related changes in long-term retention of duration and their effects on time judgement. Children aged 3, 5, and 8 years old were given a temporal bisection task with or without a 15-min interfering task (Experiment 1), or a retention delay lasting for 0 min, 15 min, or 24 hr (Experiment 2) between the presentation of the standard durations and the comparison stimulus durations. An interfering task and the increase of the retention delay significantly decreased the time sensitivity in the 3- and the 5-year-olds, and to a greater extent in the younger children, but had no effect in the 8-year-olds. This decrease in time sensitivity with the interfering task or the retention delay might be due to an increase in the variability of the remembered duration.     

不同特征维度下ADHD儿童的任务切换特点

本研究采用双向刺激设置,通过操纵两实验的特征维度,以考察任务维度对ADHD儿童任务切换的影响。结果发现,在两个实验中,相对于正常组儿童,ADHD儿童在任务切换上都表现出缺损。当注意维度相同时,ADHD儿童在固定顺序上的切换损耗大于随机顺序,但在跨维度任务中,ADHD儿童在固定顺序上的切换损耗则小于随机顺序,这与正常儿童的表现模式不一致。该结果表明,工作记忆会对ADHD儿童产生影响,但这取决于任务的特征维度是否一致。     

Semantic organization in the young child: Evidence for the development of semantic feature systems

In two experiments, 5-, 7-, 9-, and 11-year-old children and college students were presented on each trial with a sentence followed by a probe word. Their task was to indicate whether the probe was in the sentence or not. Of primary interest were the false recognitions and the correct latencies that occurred when the probe word was a synonym or antonym of one of the words in the sentence (Experiment I) or when the probe was a subordinate, superordinate, part, or whole (Experiment II). The younger children were more affected by synonymy than antonymy, although the older children and adults were not. At all ages, the categorical relationships caused more recognition confusion than the partwhole relationships. Subjects were more affected when the probe was a superordinate than when it was a subordinate, and somewhat more affected when the probe was the whole than when it was the part. These results suggest that children as young as 5 years of age have well-organized conceptual systems based on shared meaning components.     

Avoidance extinction in goldfish

Independent groups of goldfish trained to avoid shock in a shuttlebox situation were presented with several extinction procedures in which the relationships between the conditioned stimulus and shock were altered and/or response contingencies removed. Random shock presentations, equivalent to the number of shocks received during avoidance acquisition, resulted in response decrements similar to those obtained when the conditioned stimulus was presented alone. Pairing the conditioned stimulus with shock on every trial, however, served to maintain response levels. When response-contingent punishment was superimposed upon these Pavlovian pairings, performance was facilitated slightly although punishment alone resulted in somewhat faster response reduction than that produced by exposure only to the conditioned stimulus. Extinction of avoidance responding produced by exposure to the conditioned stimulus alone was dependent on the total duration of exposure and independent of both number of stimulus onsets and response prevention. These experiments demonstrated that, in general, the procedures used to reduce avoidance responding in rats were equally effective for goldfish, with one exception: the introduction of a Pavlovian contingency following avoidance acquisition, making the previously avoidable shock unavoidable, maintained response probabilities near previously established levels.     

Recognition memory retention interval and information load

Two experiments were conducted to study the effect of retention interval and information load on short-term recognition memory in retarded subjects. The task consisted of an input trial of 1–15 pictures followed by a test trial of one picture, with the subject having to press different levers to indicate whether the probe picture had been present on the input trial. Retention intervals between input trial and test trial were manipulated over a range of 1–24 sec. Both accuracy and latency of response were measured. Results showed that latency increased and accuracy decreased as a function of both retention interval and number of stimuli. In addition, number of stimuli interacted with retention interval such that accuracy was not affected by retention interval when information input was small, but decreased quite dramatically at longer retention intervals when input was larger. The results were discussed in terms of current memory search models for both normal and retarded subjects.     

Reactivation-induced interference in a short-term retention paradigm

In Experiment 1 it was demonstrated that interference with a rat's retention of a target spatial cue decreases as the interval between prior conflicting cues and the target increases. Experiment 2 showed that interference can occur even when the interstimulus interval is long, if the memory of a conflicting cue is reactivated just prior to exposing an animal to the target cue. A third experiment suggested that these findings could not be easily interpreted in terms of a stimulus satiation effect. The implications of these findings for a trace decay model of short-term retention were discussed.     

Young children's use of temporal and spatial order information in short-term memory

Encoding and retrieval of temporal and spatial order information was investigated in the free recall and probed recognition performance of 3-, 4-, 5-, and 6-year-olds. In both tasks, three line drawings of familiar objects were presented successively in different spatial locations, so that temporal order was not confounded with spatial order. Subjects of all ages revealed an organization for the stimulus display based on the temporal sequence of presentation. With increasing age, subjects began recall more often with the first item so as to take advantage of this sequential organization. In the probed recognition task, subjects were asked questions requiring the use of temporal or spatial order information. Performance by the older subjects indicated that information about temporal and spatial order could be simultaneously encoded. The results are discussed in terms of a context theory derived from Estes's hierarchical association model.     

Enhancement of 4-year-old children's memory span for phonologically similar and dissimilar word lists

Previous research suggests that preschool children are deficient in rehearsal and that stimulus list repetitions can improve their recall, presumably by substituting for the products of rehearsal. However, the previous research included interitem or postlist retention intervals of several seconds or more. We examined the utility of list repetitions with reference to an ordinary span task in which spoken words were presented 1 s apart for immediate recall. Lists with phonologically similar versus dissimilar items were included, to determine if the overall pattern of recall could be made more similar to what is ordinarily obtained in older children. Cumulative repetition was found to cause a moderate increase in both memory span and the phonological similarity effect. Other types of list repetition provided more insight into types of stimulus redundancy that were helpful (e.g., repeated serial order information) or not helpful (e.g., forced articulatory coding) to children attempting to recall spoken lists. The underlying mnemonic processes are discussed.     

Semantic and surface codes in the memory of deaf children

In three experiments, deaf children in the age range of 6 years, 10 months to 15 years, 5 months were presented with continuous lists of items, and for each item they had to indicate whether it had appeared before on the list. Later items were related to preceding items either in surface form or in meaning or were unrelated. False-recognition errors (i.e., “yes” responses to new items) served as an index of memorial coding. In one experiment, the items presented to the subjects were printed words. The results of this experiment showed a false-recognition effect (i.e., more errors to related words than to unrelated words) for both semantically related words and orthographically similar words. In the other two experiments, the subjects viewed a series of manual signs on videotape. In these experiments, there was a false-recognition effect for signs related semantically and for signs related cherologically (i.e., similar in terms of their manual production). These results establish orthography and cherology as effective memorial codes for deaf children. The finding of a consistently strong semantic effect for young deaf children stands in contrast to findings of weak semantic effects in false-recognition studies with young hearing children. The ascendancy of semantic codes for deaf children was attributed to the absence of competition from the speech code which dominates the linguistic memory of hearing children.     

Development of comprehension of “or”: Evidence for a sequence of competencies

Comprehension of various usages of “or” was investigated in children 5–6, 7–8, and 9–10 years old, and in college students. One task used imperatives containing “or.” and investigated the set union interpretation. In a second task, one puppet asserted a statement and another puppet contradicted it: subjects were asked whether both could be right, and whether one had to be right. A third task investigated the truth conditions for disjunctions. The fourth task presented reasoning problems that tested principles of inference involving “or.” It was found that all age groups, even the youngest, could make the logical inferences involving “or.” All age groups could also perceive contradictions, but subjects were less than unanimous that one of the puppets contradicting each other had to be right. Sensible truth judgments for disjunctions began to develop around 7–8 years. Set union was elicited in only a few adults. In general, except when it indicates set union, “or” is understood substantially earlier than the current literature suggests. Logical inference is one of the first uses in which children become competent, suggesting that the basic meaning of “or” is given by inference forms for reasoning with alternatives, not by truth conditions.     

Maintaining readiness for mental rotation interferes with perceptual processes in children but with response selection in adults

Previous work revealed that mental rotation is not purely inserted into a same-different discrimination task. Instead, response time (RT) is slowed to upright stimuli in blocks containing rotated stimuli compared to RT to the same upright stimuli in pure upright blocks. This interference effect is a result of maintaining readiness for mental rotation. In two experiments we investigated previous evidence that these costs depend upon distinct sub-processes for children and for adults. In Experiment 1, the maintaining costs turned out to be independent of the visual quality of the stimulus for adults but not so for children. Experiment 2 revealed that the maintaining costs were greatly reduced for adults when they performed mental rotation as a go-no-go task, but not so for children. Taken together, both experiments provide evidence that whereas perceptual processes seem to be important for school-age children to maintain readiness for mental rotation, response selection is relevant for adults.     

Effects of sexual versus fear arousal on alcohol consumption in college males

To compare the effects of pleasant and aversive arousal on alcohol consumption, 18 male undergraduates had three weekly sessions to separately view erotic, mutilation or neutral slides in a simulated memory experiment. Following exposure to the slides, they received access to alcoholic and nonalcoholic beverages, which were presented to half the subjects in a taste rating task, and to half as the result of engaging in an operant lever-press task. Subjects believed these tasks to be distractors during a purported retention interval. Self-report instruments and basal skin conductance confirmed the success of the affective manipulations. However, only the subjects using the taste task after viewing erotic slides significantly increased alcohol consumption. These results question a tension reduction model of drinking and qualify the contribution of autonomic arousal to motivation for drinking.     

Pupillary changes during recall in children

Seven children aged 7–9 years were auditorily presented five-digit numbers for retention intervals of 0 and 10 sec. Pupil size was recorded during stimulus presentation, retention interval, and recall of items. Findings indicate that pupil dilation occurs during encoding and retrieval of stimulus items with pupillary constriction occurring during retention of the items. The pupillary change functions obtained with children were found to be very similar to those obtained with older subjects.     

Stimulus factors and listening strategies in auditory memory: An experimental demonstration

Three experiments are reported in which digits spoken at different rates were recalled and monitored. In Experiment I, digits to be recalled were embedded in varying levels of noise. In Experiment II noise was presented only during the inter-digit intervals, either to the same or to the opposite ear as the digits. In Experiment III Ss monitored these sequences for a specified digit and reported its successor. Stimulus rate and signal-to-noise ratio affected perceptual processing time, as evidenced by the frequency and relative proportion of item and order errors. These stimulus factors induce listening strategies that influence the shape of the serial position curve and that persist after stimulus conditions are changed. The data are consistent with a two-stage processing model for the temporal course of speech perception and the nature of listening strategies.     

Conditions under which children experience inhibitory difficulty with a "button-press" go/no-go task

Go/no-go tasks seem to provide a simple marker of inhibitory development in young children. Children are told to respond to one stimulus on go trials but to make no response to another stimulus on no-go trials; responding on no-go trials is assumed to reflect a failure to inhibit the go response. However, there is evidence to suggest that a type of go/no-go task, which we call the "button-press" task, does not require inhibition. We investigated the conditions under which young children (M=3 years 6 months, N=120) experience inhibitory difficulty with this type of task. The data suggest that the speed of stimulus presentation is crucial and that other studies using this type of task have presented the stimuli too briefly. The importance of establishing the inhibitory credentials of a task before it is used as a marker of inhibitory control is emphasized.