When the whole is more than the sum of its parts: Group motivation gains in the wild

Whereas negative effects of groups on individual motivation have been reported for many years, recent research has begun to show when and why working in a group can produce motivation gains compared to individual work. So far, this evidence has been limited to laboratory settings and rather simple tasks. Using data from swimming competitions at the 2008 Olympics, evidence is presented that motivation gains in groups also occur in field settings with more complex tasks. Based on an instrumentality × value approach, we expect that late positions in a relay trigger motivation gains in groups due to an increase in perceived indispensability for the group outcome. This idea has been initially tested in a pilot study with competitive swimmers, demonstrating that perceived indispensability for the relay outcome indeed increases with later serial positions in a relay. Moreover, the main study with data from the 2008 Olympics revealed performance times consistent with this pattern of indispensability perceptions: while starting swimmers in the swimming relays performed at similar levels as in their individual competitions, swimmers at the later positions showed higher performance in the relay compared to their individual competition heats.     

Divided attention: the whole is more than the sum of its parts

A divided attention situation is more than the sum of its component single tasks. Emergent aspects of the whole situation must also be considered. Three examples illustrate this. (a) When several complex stimuli (e.g., letters) are identified at once, their perceived components or features must be appropriately bundled together. Otherwise, components of two different stimuli may appear combined. This (emergent) problem is shown to depend on attention to multiple stimuli, not simply their presentation. (b) In the psychological refractory period (PRP) situation, especial difficulties arise when stimulus-response mappings are different for first and second reactions. It appears that for each reaction there is some (emergent) uncertainty over which mapping to use. This is only one of many possible emergent processes in the PRP situation. (c) When the two hands perform different actions (internally programmed sequences of taps), there is some tendency for each hand to carry out the action assigned to the other. This again is only a small part of the (emergent) problem of motor coordination. Thus the simple idea of competition for limited resources captures only a part of the problem of divided attention. Performance under divided attention will reflect an interaction between resource limitation, single task processes, and emergent aspects of the whole situation.     

When the event is more than the sum of its parts: 9-month-olds' long-term ordered recall

Research suggests that 9-month-old infants are able to recall single object-specific actions over delays of 24 hours. In the present research we investigated whether 9-month-olds are able to recall over more extended delays, and to recall the temporal order of events, as well as the individual actions in them. In addition, we investigated whether recall can be enhanced by pre- and/or re-exposure to target events. Using elicited imitation of novel, multi-step event sequences, we demonstrated that, as a group, 9-month-olds are able to recall target actions after delays of five weeks. However, after this long delay, only 45% of the infants recalled the temporal order of the events. Re-exposure to events during the delay interval proved necessary for boys, but not for girls; pre-exposure to events did not affect later recall. The implications of individual differences in infants' recall ability for the understanding of the development of the neural correlates of declarative memory are discussed.     

The rod-and-frame effect: the whole is less than the sum of its parts

Since the discovery of the influence of the tilted frame on the visual perception of the orientation perceived as vertical (VPV), the frame has been treated as a unitary object-a Gestalt. We evaluated the effect of 1-line, 2-line, 3-line, and 4-line (square frame) stimuli of two different sizes, and asked whether the influence of the square frame on VPV is any greater than the additive combination of separate influences produced by the individual lines constituting the frame. We found that, for each size, the square frame is considerably less influential than the additive combination of the influences of the individual lines. The results conform to a mass action rule, in which the lengths and orientations of the individual line components are what matters and the organization of the lines into a square does not-no higher-level Gestalt property is involved in the induction effect on VPV.     

The whole is indeed more than the sum of its parts: perceptual averaging in the absence of individual item representation

We tested Ariely's (2001) proposal that the visual system represents the overall statistical properties of sets of objects against alternative accounts of rapid averaging involving sub-sampling strategies. In four experiments, observers could rapidly extract the mean size of a set of circles presented in an RSVP sequence, but could not reliably identify individual members. Experiment 1 contrasted performance on a member identification task with performance on a mean judgment task, and showed that the tasks could be dissociated based on whether the test probe was presented before or after the sequence, suggesting that member identification and mean judgment are subserved by different mechanisms. In Experiment 2, we confirmed that when given a choice between a probe corresponding to the mean size of the set and a foil corresponding to the mean of the smallest and largest items only, the former is preferred to the latter, even when observers are explicitly instructed to average only the smallest and largest items. Experiment 3 showed that a test item corresponding to the mean size of the set could be reliably discriminated from a foil but the largest item in the set, differing by an equivalent amount, could not. In Experiment 4, observers rejected test items dissimilar to the mean size of the set in a member identification task, favoring test items that corresponded to the mean of the set over items that were actually shown. These findings suggest that mean representation is accomplished without explicitly encoding individual items.     

Cognitive neuroscience of actions: a whole is greater than the sum of its parts

The purpose of the present issue of Brain and Cognition is to demonstrate that the strength of neuroscience is in its multidisciplinary approach to understand events. Here we are concerned with the domain of action recognition and production. Seven articles have been selected as representative studies of actions carried out in different areas of neuroscience such as neuropsychology, neurophysiology, and cognitive science. Although each addresses different questions within the field, the articles share a common neuroscientific knowledge, as can be readily gathered from the references cited in each article.     

The perception of a face is no more than the sum of its parts

When you see a person's face, how do you go about combining his or her facial features to make a decision about who that person is? Most current theories of face perception assert that the ability to recognize a human face is not simply the result of an independent analysis of individual features, but instead involves a holistic coding of the relationships among features. This coding is thought to enhance people's ability to recognize a face beyond what would be expected if each feature were shown in isolation. In the study reported here, we explicitly tested this idea by comparing human performance on facial-feature integration with that of an optimal Bayesian integrator. Contrary to the predictions of most current notions of face perception, our findings showed that human observers integrate facial features in a manner that is no better than would be predicted by their ability to use each individual feature when shown in isolation. That is, a face is perceived no better than the sum of its individual parts.     

The perception of a familiar face is no more than the sum of its parts

Why do faces become easier to recognize with repeated exposure? Previous research has suggested that familiarity may induce a qualitative shift in visual processing from an independent analysis of individual facial features to analysis that includes information about the relationships among features (Farah, Wilson, Drain, & Tanaka Psychological Review, 105, 482–498, 1998; Maurer, Grand, & Mondloch Trends in Cognitive Science, 6, 255–260, 2002). We tested this idea by using a “summation-at-threshold” technique (Gold, Mundy, & Tjan Psychological Science, 23, 427–434, 2012; Nandy & Tjan Journal of Vision, 8, 3.1–20, 2008), in which an observer’s ability to recognize each individual facial feature shown independently is used to predict their ability to recognize all of the features shown in combination. We find that, although people are better overall at recognizing familiar as opposed to unfamiliar faces, their ability to integrate information across features is similar for unfamiliar and highly familiar faces and is well predicted by their ability to recognize each of the facial features shown in isolation. These results are consistent with the idea that familiarity has a quantitative effect on the efficiency with which information is extracted from individual features, rather than a qualitative effect on the process by which features are combined.     

Coherent plaids are preattentively more than the sum of their parts

We investigated whether plaids activate preattentive mechanisms that are distinct from those activated by their component gratings. Observers searched for a target plaid, the sum of two perpendicular components in a circular window (radius = 0.65°). The target was present on half the trials. On all trials, half of the distractors had the same frequency and orientation as one component of the plaid, and the rest were the same as the other component. The target and the distractors were arrayed evenly on a circle (radius = 2.36°) around fixation. Target and distractor contrasts were randomly perturbed up to ±30%. The following results held for each of the 6 participants tested. (1) When F1 = 2 c/deg and F2 = 5.25 c/deg, response times (RTs) increased significantly when set size (number of distractors plus target, if present) was increased from four to eight. (2) When the spatial frequencies of both plaid components were the same (i.e., both 2 c/deg or both 5.25 c/deg), RTs increased very slightly, if at all, when set size was increased from four to eight. These results suggest the existence of a preattentive, plaid-sensitive mechanism with band-limited input that does not respond to individual grating components.     

A whole face is more than the sum of its halves: Interactive processing in face perception

Facial information is processed interactively. Yet, such interactive processing has been examined for discrimination of face parts rather than complete faces. Here we assess interactive processing using a novel paradigm in which subjects discriminate complete faces. Face stimuli, which comprise unilateral facial information (hemifaces) or bilateral facial information from one face (consistent) or two different faces (inconsistent), are shown centrally in a face‐matching task. If each half of a complete face is processed independently, accuracy for complete faces can be predicted by the union of accuracies for right and left hemifaces. However, accuracy exceeded this independence prediction for consistent faces (facilitation) and fell below the prediction for inconsistent faces (interference). These effects were reduced or absent for inverted faces. Our findings are consistent with reports of stronger interactive processing for upright than for inverted faces and they quantify effects of interactive processing on the discrimination of complete faces.     

Prior experience can influence whether the whole is different from the sum of its parts

In two conditioning experiments with humans, we found that participants’ prior experience exerted considerable influence on later learning of configural discrimination problems. Prior experience was manipulated by pre-training participants before the main acquisition stage. They either received a discrimination problem that encouraged an elemental solution (A+, B−, AB+, CD− in Experiment 1 and A+, AB+, C−, CB− in Experiment 2) or one that required a configural solution (AB+, BC−, CD+, DA− in Experiment 1 and A−, AB+, C+, CB− in Experiment 2). Then, all participants were shown a discrimination that required a configural solution (E+, F+, EF− in Experiment 1 and DE+, EF−, FG+, GD− in Experiment 2). In both experiments, participants who had received elemental pre-training were impaired on the later configural problem compared to participants who had received configural pre-training. The results suggest that organisms can flexibly process stimuli elementally or configurally.     

Converging evidence that visuospatial cognition is more age-sensitive than verbal cognition

In 3 separate experiments, the same samples of young and older adults were tested on verbal and visuospatial processing speed tasks, verbal and visuospatial working memory tasks, and verbal and visuospatial paired-associates learning tasks. In Experiment 1, older adults were generally slower than young adults on all speeded tasks, but age-related slowing was much more pronounced on visuospatial tasks than on verbal tasks. In Experiment 2, older adults showed smaller memory spans than young adults in general, but memory for locations showed a greater age difference than memory for letters. In Experiment 3, older adults had greater difficulty learning novel information than young adults overall, but older adults showed greater deficits learning visuospatial than verbal information. Taken together, the differential deficits observed on both speeded and unspeeded tasks strongly suggest that visuospatial cognition is generally more affected by aging than verbal cognition.     

When food is more than nutrition: Understanding emotional eating and overconsumption

This research examines how more proximal or immediate goals of affect regulation impact goals of weight loss and maintenance. Findings suggest that both psychological and social factors play a role in eating behavior and food overconsumption. Specifically, the narratives of self‐identified emotional eaters reveal that negative emotion, prefactual thinking, and ruminative propensities play major roles in contributing to food‐related consumption. Additionally, emotional eating informants' consumption behavior is greatly impacted by the attitudes and behaviors of others. Several approaches for developing interventions for emotional eaters and furthering transformative research in obesity and overconsumption are discussed. Copyright © 2013 John Wiley & Sons, Ltd.     

The sum of the parts does not equal the whole: evidence from bihemispheric processing.

The 5 experiments in this article examine whether bihemispheric processing can be predicted from the processing observed when information is directed initially to just 1 hemisphere. Ss decided if laterally presented words rhymed with a previously presented central target. Trials varied in the degree to which the information displayed was redundant. On some trials, the same word appeared twice; in others, different words appeared, but they both led to the same decision; and finally, on some trials, different words appeared, each of which also led to a different decision. The patterns found for unilateral and bilateral trials were distinct. Furthermore, the pattern observed on bilateral trials could not be predicted from that found on unilateral trials, suggesting that interhemispheric interaction cannot be surmised from observing a hemisphere processing information in relative isolation.     

The whole moves less than the spin of its parts

When individually moving elements in the visual scene are perceptually grouped together into a coherently moving object, they can appear to slow down. In the present article, we show that the perceived speed of a particular global-motion percept is not dictated completely by the speed of the local moving elements. We investigated a stimulus that leads to bistable percepts, in which local and global motion may be perceived in an alternating fashion. Four rotating dot pairs, when arranged into a square-like configuration, may be perceived either locally, as independently rotating dot pairs, or globally, as two large squares translating along overlapping circular trajectories. Using a modified version of this stimulus, we found that the perceptually grouped squares appeared to move more slowly than the locally perceived rotating dot pairs, suggesting that perceived motion magnitude is computed following a global analysis of form. Supplemental demos related to this article can be downloaded from app.psychonomic-journals.org/content/supplemental.     

When a 12.86% mortality is more dangerous than 24.14%: implications for risk communication

Participants assessed the riskiness of 11 well-known causes of death. Each participant was presented with an estimation of the number of deaths in the population due to that particular cause. The estimates were obtained from a previous study of naive participants' intuitive estimations. For instance, based on the result of the previous study, the number of deaths due to cancer was presented as: ‘2,414 out of 10,000’, ‘1,286 out of 10,000’, ‘24.14 out of 100’ and ‘12.86 out of 100’. The estimates of deaths were presented in analogous ways for the remaining ten causes of death. It was hypothesized that the judged degree of riskiness is affected by the number of deaths, irrespective of the total possible number (such as 10,000 or 100). Results from Experiment 1 were consistent with this prediction. Participants rated cancer as riskier when it was described as ‘kills 1,286 out of 10,000 people’ than as ‘kills 24.14 out of 100 people’, and similar results were observed regarding the remaining 10 causes of death. Experiment 2 replicated this trend. Implications for risk communications are discussed. © 1997 John Wiley & Sons, Ltd.     

When less is more: Line drawings lead to greater boundary extension than do colour photographs

Is boundary extension (false memory beyond the edges of the view) determined solely by the schematic structure of the view or does the quality of the pictorial information impact this error? To examine this, colour photographs or line-drawings of 12 multi-object scenes (Experiment 1: N=64) and 16 single-object scenes (Experiment 2: N=64) were presented for 14 s each. At test, the same pictures were each rated as being the “same”, “closer-up”, or “farther away” (five-point scale). Although the layout, the scope of the view, the distance of the main objects to the edges, the background space and the gist of the scenes were held constant, line drawings yielded greater boundary extension than did their photographic counterparts for multi-object (Experiment 1) and single-object (Experiment 2) scenes. Results are discussed in the context of the multisource model and its implications for the study of scene perception and memory.