The structure of the relationship between attention and intelligence

The relationship between attention and general intelligence was investigated considering the different types of attention: alertness, sustained attention, focused attention, attentional switching, divided attention, attention according to the supervisory attentional system, attention as inhibition, spatial attention, attention as planning, interference, attention as arousal, and attention according to the assessment tradition. In a sample of 197 participants the relationship of attention and intelligence was investigated by means of structural equation modeling. The results revealed that each type of attention was substantially related to intelligence on the latent level. Furthermore, a high degree of overlap in predicting intelligence was observed for the various types of attention. Comprehensive models based on resources theory and Posner's dimensions were also investigated. The best model of the relationship between attention and intelligence included two first-order and one second-order latent variables of attention and one of intelligence. It predicted 32% of the variance of intelligence.     

Looking into your eyes: observed pupil size influences approach-avoidance responses

The eyes reveal important social messages, such as emotions and whether a person is aroused and interested or bored and fatigued. A growing body of research has also shown that individuals with large pupils are generally evaluated positively by observers, while those with small pupils are perceived negatively. Here, we examined whether observed pupil size influences approach-avoidance tendencies. Participants performed an Approach-Avoidance Task using faces with large and small pupil sizes. Results showed that pupil size influences the accuracy of arm movements. Specifically, individuals were less prone to approach a face with small pupils than a face with large pupils. Conversely, participants were less prone to avoid a face with large pupils than a face with small pupils. Collectively, these findings suggest that perceivers attend to a facial cue – pupil size – when interacting with others.     

Meta-analysis of the relationship between intelligence and inspection time

This study replicated and extended Kranzler and Jensen's [Intelligence 13 (1989) 329] meta-analysis of the relationship between inspection time (IT) and intelligence (IQ). Separate meta-analyses were conducted on obtained correlations (r's) between IT and general IQ for the total sample and for studies using samples of adults and children. Two new meta-analyses were also conducted. The first compared the IT–IQ r between visual and auditory IT; the second compared the r between strategy users and nonusers. For the total sample (N>4100), the r was −.51 after correction for artifactual effects (−.30 prior to correction). No statistically significant difference was observed between the mean corrected r of −.51 for adults and −.44 for children. The mean corrected r for visual and auditory IT measures were −.49 and −.58, respectively, suggesting that the relationship between IT and IQ is comparable across type of IT task. The mean corrected r of −.77 for strategy nonusers was statistically significantly higher than the r of −.60 for strategy users. Implications of these findings for future research are discussed.     

Skull size and intelligence, and King Robert Bruce's IQ

An estimate of someone's IQ is a potentially informative personal datum. This study examines the association between external skull measurements and IQ scores, and uses the resulting regression equation to provide an estimate of the IQ of King Robert I of Scotland (Robert Bruce, 1274–1329). Participants were 48 relatively healthy Caucasian men (age 71–76 years) resident in Scotland. Using magnetic resonance imaging data, intracranial volume estimated from external skull length and width correlated greater than .5 (p < .001) with measured intracranial area, which correlates very highly with brain volume. IQ scores estimated from the National Adult Reading Test (NART) correlated .56 (p < .001) with measured intracranial area, and .49 (p < .01) with estimated intracranial volume based on external skull width and length. The partial correlation coefficient of this latter association was .25 (p = .09) after adjustment for measured intracranial area. Thus, actual intracranial area accounts for about 74% of the variance shared by NART and estimated intracranial volume. A cast of the skull of Robert Bruce was measured and its intracranial volume estimated. A regression equation between IQ and estimated intracranial volume, based on data from the 48 subjects, estimated the IQ of Robert Bruce at about 128 (95% confidence interval 106 to  130), i.e. almost two standard deviations above the mean. NART scores show a ceiling effect, so this estimated IQ might be an underestimate. Robert Bruce's estimated high IQ is congruent with his military, political and other intellectual achievements.     

Relationships between factors of intelligence and brain volume

The recent explosion of studies aimed at determining the biological basis of intelligence has revealed that cognitive ability has a strong biological substrate. This study expands on this literature by examining the relation between cognitive ability and MRI-measured brain volume and head size in a sample of adult male siblings recruited from the London, Ontario community in Canada. It was found that brain volume correlated with IQ at 0.35 (P<0.01), thus replicating the results of past studies. Corrections for restriction of range and attenuation in both this and past studies suggest that the population value of the brain volume-IQ correlation is closer to 0.50. Head size variables, with one exception, also showed the expected positive correlations with IQ. The results of a vector analysis on factor scores indicated that the more highly g-loaded a test was the more highly it correlated with brain volume (r=0.59, P<0.01). The sum of the data suggested that although brain volume (and to a lesser extent, head size) is predictive of g, fluid ability, and memory, it does not predict crystallized ability. Unexpectedly, the higher the spatial imaging loading of a test, the less its correlation with brain volume (vector correlation=−0.84, P<0.001).     

The relationship between intelligence,working memory,academic self-esteem,and academic achievement

Academic achievement is crucial for life and long-term outcomes. The aim of the present study is to examine the joint role of cognitive (intelligence and working memory) and non-cognitive (academic self-esteem) factors in predicting academic achievement (mathematics and reading literacy) in a sample of Italian sixth and eighth graders. The results showed that within the cognitive factors considered, intelligence was the best predictor of achievement. As regards to non-cognitive factors, academic self-esteem was effective at predicting achievement after controlling for cognitive measures. Academic self-esteem was also found to have an indirect effect, mediated by intelligence, on academic achievement. Both theoretical and practical implications of the present results are discussed.     

Looking at remembering: Eye movements,pupil size,and autobiographical memory

To examine the relationship between visual imagery and autobiographical memory, eye position and pupil size were recorded while participants first searched for memories and then reconstructed the retrieved memories (Experiment 1), or only searched for memories (Experiment 2). In Experiment 1, we observed that, although recollective experience was not associated with the number of fixations per minute, memories that took longer to retrieve were linked to increased pupil size. In Experiment 2, we observed that directly retrieved memories were recalled more quickly and were accompanied by smaller pupils than generatively retrieved memories. After correcting for response time, retrieval mode also produced an effect, showing that decreased pupil size is not simply due to directly retrieved memories being recalled more quickly. These findings provide compelling evidence that objective measures, such as pupil size, can be used alongside subjective measures, such as self-reports, to distinguish between directly retrieved and generatively retrieved memories.     

The relationship between intelligence and multiple domains of religious belief: Evidence from a large adult US sample

High levels of religiosity have been linked to lower levels of intelligence in a number of recent studies. These results have generated both controversy and theoretical interest. Here in a large sample of US adults we address several issues that restricted the generalizability of these previous results. We measured six dimensions of religiosity (rather than just one or two), along with a multi-scale instrument to assess general intelligence. We also controlled for the influence of the personality trait openness on facets of religious belief and practice. The results indicated that lower intelligence is most strongly associated with higher levels of fundamentalism, but also modestly predicts central components of religiosity such as a sense of religious identification and private religious practice. Secondly, we found that a higher level of openness - often assumed to lead to lower religiosity - is weakly associated with reduced fundamentalism but with increased religious mindfulness, private religious practice, religious support, and spirituality. These new results provide a framework for understanding the links between reasoning and faith.     

Openness,economic freedom and democracy moderate the relationship between national intelligence and GDP

Recent studies have shown a consistent relationship between per-capita GDP and the average intelligence of the population. In the present paper we show that intelligence is indeed a powerful predictor of GDP. However, other variables significantly moderate the relationship. The rise in GDP with rising intelligence proved more pronounced in countries exhibiting high levels of openness, Freedom/Democracy, and economic freedom. These conditions appear to enable a country to translate its cognitive capital into material wealth.     

What makes narcissists unhappy? Subjectively assessed intelligence moderates the relationship between narcissism and psychological well-being

We investigated the relations between narcissism, self-assessed intelligence and subjective well-being. In three studies, we aimed to replicate previous findings concerning the relationship between narcissism and both objectively and subjectively assessed intelligence (Study 1), as well as to examine whether the latter influenced narcissists’ satisfaction with life (Study 2) and their mood (Study 3). The results confirmed the positive link between narcissism and self-assessed intelligence. Moreover, we demonstrated that this relationship was independent of actual abilities. In line with existing literature, we also found evidence that satisfying ego needs in this domain was a necessary precondition for narcissists’ well-being. Specifically, the results of Study 2 indicated that narcissists who evaluated their intelligence as low were not satisfied with their life. Similar results were found in Study 3: narcissists evaluating their intelligence as low experienced higher tension and lower hedonic tone.     

Hemispheric laterality measured in Rembrandt's portraits using pupil diameter and aesthetic verbal judgements

Eckhard Hess claimed that pupils dilate to pleasant images and constrict to unpleasant images. However, his work was confounded since his image's luminances and contrasts across conditions were inconsistent. We overcome this limitation and suggest a new, promising methodology for research in this area. We presented rightward or leftward facing male and female portraits by Rembrandt to observers in either their original or mirror-reversed position. Since emotional content may be expressed differently on each side of the face, we used Rembrandt's portraits since most of his males had their right-cheek exposed and females had their left-cheek exposed. This raises questions regarding the emotional and cognitive significance of such biased positioning. Simultaneously, we measured observers pupil size while asking observers to report how (dis)pleasing they found each image. We found that in viewing male portraits pupil diameter was a function of arousal. That is, larger pupil diameter occurred for images rated both low and high in pleasantness. We discuss these findings in regard to the perceived dominance of males and how emotional expressions may be driven by hemispheric laterality.     

The relationship between morningness–eveningness, time-of-day, speed of information processing, and intelligence

Morningness–Eveningness refers to individual differences in circadian phase position of spontaneous sleep–wake rhythms and to subject alertness. There is some evidence indicating that performance on cognitive tasks may be influenced by Morningness–Eveningness and time-of-day. Given the potential importance of such a finding for the assessment of cognitive ability we conducted a study assessing the relationship between Morningness–Eveningness, time-of-day, and performance on the Multidimensional Aptitude Battery IQ (MAB-IQ) and Inspection Time (IT) task. Twenty male and 50 female participants classified according to their scores on the Morningness–Eveningness dimension (Horne & Östberg, 1976) were administered the MAB and IT tasks in the morning (0900 h) and in the late afternoon (1500 h). No significant effect of time of testing, and Morningness–Eveningness was observed except for the Spatial subtest of the MAB. Morning Type-participants performed significantly worse in the morning session in Spatial subtest and better in the late afternoon session and Evening Type-participants performed significantly better in the morning than in the late afternoon session. These results do not support the hypothesis that there is a reliable relationship between Morningness–Eveningness, time-of-day and cognitive ability.     

The relationship between psychometric intelligence and inspection time

The relationship between psychometric intelligence and inspection time (IT) is reviewed. Results are contradictory, which makes questionable the reliability of this relation. Moreover, the hope that IT constitutes a measure of ‘culture fair’ intelligence has not been confirmed and its correlation with tests considered to be culture fair and tests supposedly influenced by culture are not very different. The results do not allow us to establish a greater correlation between IT and specific factors of intelligence like verbal, spatial or numerical ability. Procedural problems apparent in measuting IT could explain, in part, the variability in results.     

Reliable pupil detection and iris segmentation algorithm based on SPS

Iris segmentation is one of the complex research areas, as human eyes contain intricate details and are difficult to process. Due to the advancement of technology, security based application employ biometrics to ensure the identity of an individual. Though fingerprint is the commonly utilized biometric, iris is the most promising biometric. However, extracting the iris is not a simple task and the iris recognition accuracy depends on the effectiveness of the iris segmentation. Taking this statement into account, this work proposes a reliable iris segmentation algorithm which is based on SuperPixel Segmentation (SPS). Initially, the eyelids and pupil of the eye image are detected. This is followed by the segmentation of iris. The proposed approach is applied over four benchmark datasets such as CASIA iris V1, V2, V3 and Ubiris V2 databases. The performance of the proposed iris segmentation algorithm is compared with the existing techniques. The proposed segmentation algorithm proves its stability in all the datasets with respect to segmentation accuracy, sensitivity and specificity.     

The relationship between rational thinking and intelligence in children

This study ws designed to evaluate the efficacy of a four-session REE curriculum and examine the relationship between intelligence and the endorsement of irrational beliefs in elementary school children. A twotailedt-test administered to examine difference between pre- and post-test scores onThe Idea Inventory was statistically significant,t (1,94)=5.90,p<.0001. The Pearson product-moment correlation coefficient between pre-test scores onThe Idea Inventory and theOtis-Lennon School Ability Test failed to reach significance (r=.15) suggesting higher intelligence did not predict greater endorsement of rational beliefs. The post-test scores using the same two instruments reached a correlation coefficient of r=.51 and was statistically significant at the .01 level. A higher percentage of children who scored below the mean on theOtis-Lennon improved from pre- to post-test than children who scored above the mean.     

The relationship between emotional intelligence and ego defense mechanisms

The author examined the relationship between the components of emotional intelligence (perception of emotion, affect regulation, and emotional knowledge) and personality factors associated with adaptation, represented by the hierarchical model of defense mechanisms (M. Bond, S. Gardner, J. Christian, & J. Sigal, 1983). Bivariate correlation analyses yielded mixed results; the adaptive defense styles were correlated with overall emotional intelligence but not with the emotional perception and regulation components, as was hypothesized. Emotional knowledge was correlated with both adaptive and maladaptive defense styles and with general intelligence, as was expected. Implications for counseling and psychoeducational interventions are suggested.     

Pupil dilation patterns reflect the contents of consciousness

The study of human consciousness has historically depended on introspection. However, introspection is constrained by what can be remembered and verbalized. Here, we demonstrate the utility of high temporal resolution pupillometry to track the locus of conscious attention dynamically, over a single trial. While eye-tracked, participants heard several musical clips played diotically (same music in each ear) and, later, dichotically (two clips played simultaneously, one in each ear). During dichotic presentation, participants attended to only one ear. We found that the temporal pattern of pupil dilation dynamics over a single trial discriminated which piece of music was consciously attended on dichotic trials. Deconvolving these pupillary responses further revealed the real-time changes in stimulus salience motivating pupil dilation. Taken together, these results show that pupil dilation patterns during single-exposure to dynamic stimuli can be exploited to discern the contents of conscious attention.     

The effects of sound on pupil size and the pupil light reflex

The effects of auditory stimulation on pupil size and the pupil light reflex were investigated in 33 male volunteers. A 95dB tone caused pupillary dilation and a reduction in the amplitude of the light reflex. Although the light reflex amplitude was positively correlated with pupil size in the resting state the effects of noise on the two measures were independent since the pupillary dilation response showed a marked habituation after two presentations of the tone whereas the effect on the light reflex remained the same. People showing high impulsivity scores on the EPQ tended to have smaller pupils (i.e. low arousal). There was also a relationship between impulsivity and light reflex amplitude, but this was probably a secondary consequence of the relationship between the latter measure and pupil size in the resting state.