Using the dual-target cost to explore the nature of search target representations

Eye movements were monitored to examine search efficiency and infer how color is mentally represented to guide search for multiple targets. Observers located a single color target very efficiently by fixating colors similar to the target. However, simultaneous search for 2 colors produced a dual-target cost. In addition, as the similarity between the 2 target colors decreased, search efficiency suffered, resulting in more fixations on colors dissimilar to both target colors, which we describe as a "split-target cost." The patterns of fixations provide evidence to the type of mental representations guiding search. When the 2 targets are dissimilar, they are apparently encoded as separate and discrete representations. The fixation patterns for more similar targets can be explained with either 2 discrete target representations or a single, unitary range containing the target colors as well as the colors between them in color space.     

What characterizes life story memories? A diary study of Freshmen’s first term

We investigated whether memories are selected for the life story based on event characteristics. Sixty-one students completed weekly diaries over their first term at university. They described, dated and rated two events each week. Three months after the end of the term they completed an unexpected memory test. They recalled three memories from the diary period that were important to their life story. Three randomly selected events scoring low on importance to the life story functioned as control memories. Life story memories were rated higher on goal relevance, emotional intensity, importance and rehearsal in the diary and maintained their higher ratings at the test session, while ratings for control memories dropped off. Life story memories' content was less consistent over time but they were more accurately dated than control memories. The results suggest that event characteristics play an important role for the selection of life story memories.     

Respiratory Patterns in Students Enrolled in Schools for Disruptive Behaviour Before, During, and After Yoga Nidra Relaxation

This study investigated the effects of one session of Yoga Nidra (relaxation technique) on the breathing patterns/respiratory effort in the thoracic and abdominal chest regions of boys with disruptive behaviour using a Respiratory Inductive Plethysmography (RIP). The participants (n?=?7) were aged 10–15?years and attending NSW, Department of Education (DET) special schools for children with disruptive behaviour (DB). Results were compared with three students (one female) aged 15?years without DB. The seven boys had previously participated in a 13-week yoga program. During this program participants were progressively taught the practice of Yoga Nidra. The comparison group did not participate in the yoga program but underwent the same procedure for collection of data as the yoga group. Using Compumedics “ProFusion Polysomnography (PSG)” software and further analyses in “Polyman” European Data Format?+?(EDF), data were analysed by identifying breathing as unstable or stable. Unstable breathing was identified as fluctuations in rate/s of breathing effort, amplitude, cessation of breath, and thoracic or abdominal predominance. Results indicated that boys with disruptive behaviour generally displayed unstable breathing patterns throughout the pre-recording period and showed more stable breathing during Yoga Nidra compared with pre- or post-recording periods. There were also examples of reductions in thoracic dominance during Yoga Nidra. The comparison group’s breathing patterns throughout the three phases of the process were found to be stable.     

The QWERTY Effect: How typing shapes the meanings of words.

The QWERTY keyboard mediates communication for millions of language users. Here, we investigated whether differences in the way words are typed correspond to differences in their meanings. Some words are spelled with more letters on the right side of the keyboard and others with more letters on the left. In three experiments, we tested whether asymmetries in the way people interact with keys on the right and left of the keyboard influence their evaluations of the emotional valence of the words. We found the predicted relationship between emotional valence and QWERTY key position across three languages (English, Spanish, and Dutch). Words with more right-side letters were rated as more positive in valence, on average, than words with more left-side letters: the QWERTY effect. This effect was strongest in new words coined after QWERTY was invented and was also found in pseudowords. Although these data are correlational, the discovery of a similar pattern across languages, which was strongest in neologisms, suggests that the QWERTY keyboard is shaping the meanings of words as people filter language through their fingers. Widespread typing introduces a new mechanism by which semantic changes in language can arise.     

Transpersonal Efficacy: How Efficacy Perceptions of Single Others Influence Task Performance

In addition to self-efficacy, efficacy perceptions of others within a task environment influence task performance. I define such efficacy perceptions of single others as transpersonal efficacy and investigate it in two studies. The first shows transpersonal efficacy can drive performance. The second then builds upon the first by investigating how self- and transpersonal efficacy jointly influence task performance. Further, the role of the focal other within the task environment, as an outcome interdependent or noninterdependent partner, or as an opponent, is shown to moderate these relationships. The results are discussed in terms of the importance of investigating transpersonal efficacy due to the increasingly complex problems facing modern organizations necessitating task environments involving multiple individuals.     

Rushton’s contributions to the study of mental ability

This essay describes Rushton’s contribution to examining the nexus of intelligence, race, and genetics, specifically what I termed “Spearman’s hypothesis”. It states that Black–White differences are “most marked in just those [tests] which are known to be saturated with g”. I (Jensen) had confirmed this hypothesis using large data sets in the 1970s and 1980s and also found that Black–White differences were most marked on the more heritable rather than the more cultural subtests. Rushton confirmed and extended these findings in many highly innovative ways and demonstrated Spearman’s hypothesis applied among samples of Gypsy Roma in Serbia, and East Asian, European, South Asian, Colored and Black samples in South Africa. He has not only documented group differences in brain size, intelligence, life span, family structure, infant mortality, developmental precocity, personality, and temperament, and rates of two egg twinning, and crime among East Asians, Europeans, and Africans, but also provided a life history theory that explains them.     

Using prequestions to enhance learning from reading passages: the roles of question type and structure building ability

ABSTRACT

Answering questions before learning something (“prequestions”) enhances learning. However, these benefits usually occur for information that was asked in the prequestions (i.e. prequestioned material), and not for non-prequestioned material. We reasoned that this narrow benefit may be due to the fact that studies typically use fairly simple prequestions that have a clear answer within one part of the learning material – isolative prequestions. We explored the effects of integrative prequestions that required participants to make connections across different parts of a reading passage. Experiment 1 showed the usual benefit of isolative prequestions on prequestioned but not on non-prequestioned material, but no benefit of integrative prequestions. However, in Experiment 2 when participants were given instructions to seek the answers while reading, integrative prequestions benefited learning of both prequestioned and non-prequestioned material. Individual differences in structure building positively predicted performance, but did not interact with the effects of prequestions.     

Dual-target search for high and low prevalence X-ray threat targets

Recent studies have shown that the prevalence of target presentation in visual search has an impact on target detection rates, and also that searching for two targets leads to a decrement in performance (the “dual-target cost”). In the present experiments, we added to previous work that has examined the interaction between the prevalence effect and dual-target cost, and also to previous work that has examined a full range of prevalence levels. We found no interaction between the dual-target cost and prevalence effect, though the response criterion in dual-target search did interact with target prevalence in an unexpected manner. Furthermore, we detected anasymmetry in the prevalence effect: It was more marked for high than low prevalence. Implications for real-world tasks are discussed.