Polychronicity and Multitasking: A Diary Study at Work

Polychronicity and multitasking have been described as being indispensible in work today because they enable people to use their time flexibly and effectively. We conducted a diary study among 93 employees during the mornings and evenings of 5 consecutive workdays (n = 418 observations). The study used hierarchical linear modeling with polychronicity and other personal characteristics at the person level, and multitasking behavior along with multitasking opportunities, interruptions, and unplanned work as antecedents, and affective well-being and self-rated performance as outcomes at the day level. We found several relations between antecedents and multitasking, as well as between multitasking and consequences. Polychronicity interacts with these relationships, such that polychronic individuals’ affective well-being and self-rated performance are less affected on days with much multitasking compared to monochronic individuals.     

Recognition memory strength is predicted by pupillary responses at encoding while fixation patterns distinguish recollection from familiarity

Thirty-five healthy participants incidentally encoded a set of man-made and natural object pictures, while their pupil response and eye movements were recorded. At retrieval, studied and new stimuli were rated as novel, familiar (strong, moderate, or weak), or recollected. We found that both pupil response and fixation patterns at encoding predict later recognition memory strength. The extent of pupillary response accompanying incidental encoding was found to be predictive of subsequent memory. In addition, the number of fixations was also predictive of later recognition memory strength, suggesting that the accumulation of greater visual detail, even for single objects, is critical for the creation of a strong memory. Moreover, fixation patterns at encoding distinguished between recollection and familiarity at retrieval, with more dispersed fixations predicting familiarity and more clustered fixations predicting recollection. These data reveal close links between the autonomic control of pupil responses and eye movement patterns on the one hand and memory encoding on the other. Moreover, the data illustrate quantitative as well as qualitative differences in the incidental visual processing of stimuli, which are differentially predictive of the strength and the kind of memory experienced at recognition.     

Developmental trajectory of number acuity reveals a severe impairment in developmental dyscalculia

Developmental dyscalculia is a learning disability that affects the acquisition of knowledge about numbers and arithmetic. It is widely assumed that numeracy is rooted on the “number sense”, a core ability to grasp numerical quantities that humans share with other animals and deploy spontaneously at birth. To probe the links between number sense and dyscalculia, we used a psychophysical test to measure the Weber fraction for the numerosity of sets of dots, hereafter called number acuity. We show that number acuity improves with age in typically developing children. In dyscalculics, numerical acuity is severely impaired, with 10-year-old dyscalculics scoring at the level of 5-year-old normally developing children. Moreover, the severity of the number acuity impairment predicts the defective performance on tasks involving the manipulation of symbolic numbers. These results establish for the first time a clear association between dyscalculia and impaired “number sense”, and they may open up new horizons for the early diagnosis and rehabilitation of mathematical learning deficits.     

Perspective taking and cognitive flexibility in the Dimensional Change Card Sorting (DCCS) task

In a study with 79 3-year-olds, we confirm earlier findings that separating the sorting dimensions improve children's performance on the Dimensional Change Card Sorting (DCCS) task. We also demonstrate that the central reason for this facilitation is that the two sorting dimensions are not integral features of a single object. Spatial separation of the sorting dimensions has no additional significant influence. This finding highlights the important role of objects with respect to children's attentional flexibility. Implications for current theories on the DCCS task and for the development of perspective taking and cognitive flexibility are discussed.     

Believing in one’s equal rights: Self-respect as a predictor of assertiveness

In the present research self-respect is defined as a person’s ability to see the self as someone who has the same basic rights and dignity as others. Self-respect fills a gap in previous theorizing on the self because unlike other self-concepts it can be linked to assertiveness and claim making. Self-respect was empirically distinguished from self-competence and self-confidence (Study 1) as well as from psychological entitlement, self-esteem and self-acceptance (Study 2). Self-respect predicted assertive responses above and beyond these other self-scales in two correlational studies (Studies 1 and 3) and one experiment (Study 2). As predicted, self-respect was not related to aggressive responses, but psychological entitlement was (Studies 2 and 3). Implications for future research are discussed.     

A visual object stimulus database with standardized similarity information

Although many visual stimulus databases exist, none has data on item similarity levels for multiple items of each kind of stimulus. We present such data for 50 sets of grayscale object photographs. Similarity measures between pictures in each set (e.g., 25 different buttons) were collected using a similarity-sorting method (Goldstone, Behavior Research Methods Instruments & Computers, 26(4):381–386, 1994). A validation experiment used data from 1 picture set and compared responses from standard pairwise measures. This showed close agreement. The similarity-sorting measures were then standardized across picture sets, using pairwise ratings. Finally, the standardized similarity distances were validated in a recognition memory experiment; false alarms increased when targets and foils were more similar. These data will facilitate memory and perception research that needs to make comparisons between stimuli with a range of known target–foil similarities.     

Accessing causal relations in semantic memory

Most studies investigating semantic memory have focused on taxonomic or associative relations. Little is known about how other relations, such as causal relations, are represented and accessed. In three experiments, we presented participants with pairs of words one after another, describing events that referred to either a cause (e.g., spark) or an effect (e.g., fire). We manipulated the temporal order of word presentation and the question participants had to respond to. The results revealed that questions referring to the existence of a causal relation are answered faster when the first word refers to a cause and the second word refers to its effect than vice versa. However, no such asymmetry was observed with questions referring to the associative relation. People appear to distinguish the roles of cause and effect when queried specifically about a causal relation, but not when the same information is evaluated for the presence of an associative relation.     

Does Octopus vulgaris have preferred arms?

Previous behavioral studies in Octopus vulgaris revealed lateralization of eye use. In this study, the authors expanded the scope to investigate arm preferences. The octopus's generalist hunting lifestyle and the structure of their arms suggest that these animals have no need to designate specific arms for specific tasks. However, octopuses also show behaviors, like exploration, in which only single or small groups of arms are involved. Here the authors show that octopuses had a strong preference for anterior arm use to reach for and explore objects, which points toward a task division between anterior and posterior arms. Four out of 8 subjects also showed a lateral bias. In addition, octopuses had a preference for a specific arm to reach into a T maze to retrieve a food reward. These findings give evidence for limb-specialization in an animal whose 8 arms were believed to be equipotential.     

Further exploration memory bias in compulsive washers

The aim of the present study was to replicate Radomsky and Rachman's findings on memory bias in obsessive-compulsive disorder (OCD), using the same procedure but an increased sample size, more specific control groups, and a full analysis of contamination attribution data. Sixteen OCD-washers, 16 OCD-checkers, 16 social phobic patients and 16 non-anxious controls were presented with 50 'clean' or 'dirty' objects. After this incidental encoding phase, participants were asked to freely recall the objects, to rate their anxiety when almost touching each object, and, finally, to attribute each object to one of the two contamination conditions ('clean' or 'dirty'). Verbal episodic memory was also assessed with the California Verbal Learning Test. The results indicate that, contrary to Radomsky and Rachman's findings, OCD-washers did not differ from the other participants in their memory for 'clean' and 'dirty' objects. However, the OCD-washers recalled more accurately the 'dirty' source of contamination than the 'clean' source. This result was specific to the OCD-washers, and suggests a memory bias for contextually threatening information. The differences between our findings and those published by Radomsky and Rachman's are discussed.     

Risk and protective factors for marijuana use and problems with use in a national sample of female Ecuadorian secondary school students

This study investigated risk and protective factors for marijuana use and problems with use in Ecuadorian girls in an attempt to inform this growing problem. Female secondary school students (N = 16,310; M = 15.02, SD = 1.73 years) who completed the 2016 national survey of drug use participated. The likelihood of lifetime marijuana use, reported by 7.3% of the sample, was predicted by older age, greater perceived access to marijuana and affiliation with tobacco- and marijuana-using peers; aspects of parental monitoring and perceived physical safety in and around school were negatively related to the probability of use. Among girls reporting any marijuana use, age, frequency of past year use, ease of access and affiliation with marijuana-using peers was positively associated with marijuana use problems. These data support the roles of both parents and communities in reducing marijuana use among Ecuadorian girls and highlight the important role of peer influence.