Is the Flynn effect on g?: A meta-analysis

Black/White differences in mean IQ have been clearly shown to strongly correlate with g loadings, so large group differences on subtests of high cognitive complexity and small group differences on subtests of low cognitive complexity. IQ scores have been increasing over the last half century, a phenomenon known as the Flynn effect. Flynn effect gains are predominantly driven by environmental factors. Might these factors also be responsible for group differences in intelligence? The empirical studies on whether the pattern of Flynn effect gains is the same as the pattern of group differences yield conflicting findings. A psychometric meta-analysis on all studies with seven or more subtests reporting correlations between g loadings and standardized score gains was carried out, based on 5 papers, yielding 11 data points (total N = 16,663). It yielded a true correlation of − .38, and none of the variance between the studies could be attributed to moderators. It appears that the Flynn effect and group differences have different causes. Suggestions for future research are discussed.     

Is school bullying really on the rise?

Whether bullying in schools is increasing, as is widely believed, was investigated drawing upon empirical studies undertaken in a wide range of countries in which findings had been published describing its prevalence at different points in time between 1990 and 2009. Results do not support the view that reported bullying in general has increased during this period; in fact, a significant decrease in bullying has been reported in many countries. However, there are some indications that cyber bullying, as opposed to traditional bullying, has increased, at least during some of this period. The reported decreases in the prevalence of school bullying are consistent with reports of significant but small reductions in peer victimisation following the implementation of anti-bullying programs in schools world-wide.     

Who discovered the Flynn effect? A review of early studies of the secular increase of intelligence

Flynn has been credited with having discovered the increase in IQs that has been reported in a number of countries during most of the twentieth century and that has come to be known as “the Flynn effect”. This paper documents and discusses a number of reports of increases in IQs that were published from 1936 onwards before the phenomenon was rediscovered by  and . These early reports showed that the Flynn effect is fully present in pre-school children, does not increase during the school age years, and is greater for non-verbal abilities than for verbal abilities.     

What has caused the Flynn effect? Secular increases in the Development Quotients of infants

Results of five studies show that during the second half of the twentieth century there were increases in the Development Quotients (DQs) of infants in the first two years of life. These gains were obtained for the Bayley Scales in the United States and Australia, and for the Griffiths Test in Britain. The average of 19 data points is a DQ gain of approximately 3.7 DQ points per decade. Similar gains of approximately 3.9 IQ points per decade have been present among preschool children aged 4–6 years. These gains are about the same as the IQ gains of school age students and adults on the Wechsler and Binet tests. This suggests that the same factor has been responsible for all these secular gains. This rules out improvements in education, greater test sophistication, etc. and most of the other factors that have been proposed to explain the Flynn effect. It is proposed that the most probable factor has been improvements in pre-natal and early post-natal nutrition.     

The effect of word length in short-term memory: Is rehearsal necessary?

Three experiments investigated the effect of word length on a serial recognition task when rehearsal was prevented by a high presentation rate with no delay between study and test lists. Results showed that lists of short four-phoneme words were better recognized than lists of long six-phoneme words. Moreover, this effect was equivalent to that observed in conditions in which there was a delay between lists, thereby making rehearsal possible in the interval. These findings imply that rehearsal does not play a central role in the origin of the word length effect. An alternative explanation based on differences in the degree of retroactive interference generated by long and short words is proposed.     

The irrelevant sound effect in short-term memory: Is there developmental change?

With two experiments, effects of irrelevant speech and classroom noise on serial recall of common nouns presented pictorially were investigated in children and adults. Experiment 1 used fixed list lengths for children (first graders) and adults. Experiment 2 used list lengths adjusted to participants' (second–third graders, adults) individual spans. In both experiments, children and adults were equally impaired by irrelevant speech. This contrasts with a related study (differences in methodology) by Elliott (2002), who reported severe increase in the detrimental impact of irrelevant speech with decreasing age. In both experiments, classroom noise had no effect in overall analyses. For Experiment 1, however, separate group analyses revealed impairment in children. Results suggest that effects of irrelevant sounds on serial recall stem from two separate mechanisms: Specific interference due to the sounds' automatic access to short-term memory, and/or attention capture. Only for the latter there is developmental change.     

Is the inversion effect in rhesus monkeys face-specific?

This study investigated the face inversion effect in rhesus monkeys (Macaca mulatta). Face stimuli consisted of ten black-and-white examples of unfamiliar rhesus monkey faces, brown capuchin faces, and human faces. Two non-face categories included ten examples of automobiles and abstract shapes. All stimuli were presented in a sequential matching-to-sample format using an automated joystick-testing paradigm. Subjects performed significantly better on upright than on inverted presentations of automobiles, rhesus monkey and capuchin faces, but not human faces or abstract shapes. These results are inconsistent with data from humans and chimpanzees that show the inversion effect only for categories of stimuli for which subjects have developed expertise. The inversion effect in rhesus monkeys does not appear to be face-specific, and should therefore not be used as a marker of specialized face processing in this species. Received: 18 November 1998 / Accepted after revision: 9 May 1999     

The effect of word length in short-term memory: Is rehearsal necessary?

Three experiments investigated the effect of word length on a serial recognition task when rehearsal was prevented by a high presentation rate with no delay between study and test lists. Results showed that lists of short four-phoneme words were better recognized than lists of long six-phoneme words. Moreover, this effect was equivalent to that observed in conditions in which there was a delay between lists, thereby making rehearsal possible in the interval. These findings imply that rehearsal does not play a central role in the origin of the word length effect. An alternative explanation based on differences in the degree of retroactive interference generated by long and short words is proposed.     

Phonological recoding: Is the regularity effect consistent?

An attempt was made to distinguish between the dual-access and the activation and synthesis models of word identification. Word regularity and consistency were factorially manipulated. In two experiments lexical decisions were required, and in two the task was word naming. Within each task, comparisons were made of the effects achieved by manipulating the degree to which subjects were free to rely on a phonological, rather than a visual, stimulus code. The results suggested that lexical access generally involves the activation of lexical entries that are visually similar to the target, but that subjects do favor a phonological code when the task requires the naming of words only. The data were interpreted as requiring a model incorporating elements of both the dual-access and the activation and synthesis frameworks.     

A secular decline in the strength of Spearman’s g in Japan

It has been found in the United States and in Scotland that the subtests of the WISC-R and WAIS-R are more highly intercorrelated among low-intelligence groups than among high. The value of the intercorrelations is a measure of the strength of Spearman’s g, and hence Spearman’s g is apparently stronger among populations with low intelligence. Since intelligence has been increasing over time, it should follow that the strength of g has shown a corresponding decline. Evidence from the standardization samples of the WISC and WISC-R in Japan shows that this is the case.     

The SNARC effect: an instance of the Simon effect?

Our aim was to investigate the relations between the Spatial-Numerical Association of Response Codes (SNARC) effect and the Simon effect. In Experiment 1 participants were required to make a parity judgment to numbers from 1 to 9 (without 5), by pressing a left or a right key. The numbers were presented to either the left or right side of fixation. Results showed the Simon effect (left-side stimuli were responded to faster with the left hand than with the right hand whereas right-side stimuli were responded to faster with the right hand), and the SNARC effect (smaller numbers were responded to faster with the left hand than with the right hand, whereas larger numbers were responded to faster with the right hand). No interaction was found between the Simon and SNARC effects, suggesting that they combine additively. In Experiment 2 the temporal distance between formation of the task-relevant non-spatial stimulus code and the task-irrelevant stimulus spatial code was increased. As in Experiment 1, results showed the presence of the Simon and SNARC effects but no interaction between them. Moreover, we found a regular Simon effect for faster RTs, and a reversed Simon effect for longer RTs. In contrast, the SNARC effect did not vary as a function of RT. Taken together, the results of the two experiments show that the SNARC effect does not simply constitute a variant of the Simon effect. This is considered to be evidence that number representation and space representation rest on different neural (likely parietal) circuits.     

Is the attentional blink effect located in short-term memory?

The attentional blink (AB) effect is characterized by a failure to detect a second target following the identification of a previous target in a RSVP stream. This effect has been attributed to capacity limitations at a central level of visual information processes. Postperceptual models suppose that the AB locus is located in short-term memory. To test this hypothesis, we investigated the influence of a short-term memory deficit on the AB effect in a patient with such a deficit. The three main results of this study are (1) the persistence of an AB effect, (2) a large number of T1 missed identifications and (3) a T2 detection deficit for a specific delay (367 ms). These results indicate that a short-term memory deficit disrupts the processing of each target (T1 and T2) but does not product an abolition of the AB effect.     

Adaptive memory: Is the animacy effect on memory due to emotional arousal?

Animate entities are often better remembered than inanimate ones. The proximal mechanisms underlying this animacy effect on recall are unclear. In two experiments, we tested whether the animacy effect is due to emotional arousal. Experiment 1 revealed that translations of the animate words used in the pioneering study of Nairne et al. (Psychological science, 24, 2099–2105, 2013) were perceived as being more arousing than translations of the inanimate words, suggesting that animacy might have been confounded with arousal in previous studies. In Experiment 2, new word lists were created in which the animate and inanimate words were matched on arousal (amongst several other dimensions), and participants were required to reproduce the animate and inanimate words in a free recall task. There was a tendency towards better memory for arousing items, but robust animacy effects were obtained even though animate and inanimate words were matched on arousal. Thus, while arousal may contribute to the animacy effect when it is not carefully controlled for, it cannot explain the memory advantage of animate items.     

Is the picture bizarreness effect a generation effect?

Bizarre stimuli usually facilitate recall compared to common stimuli. This investigation explored the so-called bizarreness effect in free recall by using 80 simple line drawings of common objects (common vs bizarre). 64 subjects participated with 16 subjects in each group. Half of the subjects received learning instructions and the other half rated the bizarreness of each drawing. Moreover, drawings were presented either alone or with the name of the object under mixed-list encoding conditions. After the free recall task, subjects had to make metamemory judgments about how many items of each format they had seen and recalled. The key result was that a superiority of bizarre pictures over common ones was found in all conditions although performance was better when the pictures were presented alone than with their corresponding label. Subsequent metamemory judgments, however, showed that subjects underestimated the number of bizarre items actually recalled.     

Potentiation in young infants: The origin of the prior knowledge effect?

In two experiments with 6-month-old infants, we found that prior learning of an operant task (remembered for 2 weeks) mediated new learning of a modeling event (remembered for only 1 day) and increased its recall. Infants first learned to associate lever pressing with moving a toy train housed in a large box. One or 2 weeks later, three target actions were modeled on a hand puppet while the train box (a retrieval cue) was in view. Merely retrieving the train memory strengthened it, and simultaneously pairing its retrieved memory with the modeled actions potentiated their learning and recall. When paired 1 week later, deferred imitation increased from 1 day to 4 weeks; when paired 2 weeks later, it increased from 1 day to 6 weeks. The striking parallels between potentiated learning in infants and the prior knowledge effect in adults suggests that the prior knowledge effect originates in early infancy.     

Is beauty talent? Sex interaction in the attractiveness halo effect

Two experiments were performed to replicate and extend previous findings of judgmental bias which favors physically attractive people. In the first experiment male and female subjects judged an essay purportedly written by an attractive or an unattractive female author. The attractive author was rated as significantly more talented by male judges. Female judges rated the attractive author as less talented, although this difference was not statistically significant. A second experiment concerned ratings by males and females of essays written by attractive or unattractive male authors. The results suggested that the attractiveness halo effect does not occur for male authors.A similar version of this article was presented at the meeting of the Western Psychological Association, Los Angeles, April 1976. Thanks are due to Jan Ault, Lynn Barrett, Paul Leathem, Mike Orenich, Bill Starns, and Meg Wiedlin for their participation in various stages of the research.     

Are religious ‘nones’ secular? The case of the nones in Australia

The number of people with no religious affiliation (religious ‘nones’) is growing in the west. However, little is known about the religiosity – or non-religiosity – of these people. Using representative survey data, this report examines the levels of religious belief and practice among Australian religious nones and compares this with those who identify with a religion. It is found that there is a deep congruence with no religious affiliation and other ways of being considered non-religious.     

Is perceptual salience needed in explanations of the isolation effect?

The isolation effect is a well-known phenomenon that has a well-accepted explanation: An item that is isolated on a list becomes perceptually salient, which leads to extra rehearsal that enhances memory for the isolate. To evaluate this hypothesis, the authors isolated an item near the beginning of a list. Immediately after each item was presented for study, participants judged the likelihood of recalling the item. Although the isolation effect occurred, participants did not judge the isolate as being more memorable than the preceding item, suggesting that the isolate was not salient. In a second experiment, participants rehearsed items aloud. Isolation at the beginning of the list did not produce extra rehearsal. By contrast, isolation in the middle of the list produced extra rehearsal; however, even when the isolate did not receive extra rehearsal, an isolation effect was evident. Thus, salience and extra rehearsal are not necessary for producing an isolation effect.     

Is there an effect of handedness on the position of the egocentric reference?

Forty normal subjects (20 left-handed; 20 right-handed) were submitted to a proprioceptive straight ahead pointing task while blindfolded to study the effect of the hand used and of the hand preference on the estimation of the subjective sagittal middle. Results showed that left-handed and right-handed subjects both deviated to the left of the objective sagittal middle and presented an effect of the hand used and of the starting point affecting their straight ahead performance in a similar way. In all subjects whatever their manual preference, using the left hand and starting 30 degrees to left induced a tendency to deviate to the same side, whereas using the right hand and starting 30 degrees to right induced a tendency to place the subjective middle to the right of the objective middle. These results are interpreted with regard to the hypothesis of a cortical control of the position of the egocentric reference.