Out of sight,out of mind: Matching bias underlies confirmatory visual search

Confirmation bias has recently been reported in visual search, where observers who were given a perceptual rule to test (e.g. “Is the p on a red circle?”) search stimuli that could confirm the rule stimuli preferentially (Rajsic, Wilson, & Pratt, Journal of Experimental Psychology: Human Perception and Performance, 41(5), 1353–1364, 2015). In this study, we compared the ability of concrete and abstract visual templates to guide attention using the visual confirmation bias. Experiment 1 showed that confirmatory search tendencies do not result from simple low-level priming, as they occurred when color templates were verbally communicated. Experiment 2 showed that confirmation bias did not occur when targets needed to be reported as possessing or not possessing the absence of a feature (i.e., reporting whether a target was on a nonred circle). Experiment 3 showed that confirmatory search also did not occur when search prompts referred to a set of visually heterogenous features (i.e., reporting whether a target on a colorful circle, regardless of the color). Together, these results show that the confirmation bias likely results from a matching heuristic, such that visual codes involved in representing the search goal prioritize stimuli possessing these features.     

Out of mind, but not out of sight: Intentional control of visual memory

Does visual information enjoy automatic, obligatory entry into memory, or, after such information has been seen, can it still be actively excluded? To characterize the process by which visual information could be excluded from memory, we used Sternberg’s (1966, 1975) recognition paradigm, measuring visual episodic memory for compound grating stimuli. Because recognition declines as additional study items enter memory, episodic recognition performance provides a sensitive index of memory’s contents. Three experiments showed that an item occupying a fixed serial position in a series of study items could be intentionally excluded from memory. In addition, exclusion does not depend on lowlevel information, such as the stimulus’s spatial location, orientation, or spatial frequency, and does not depend on the precise timing of irrelevant information, which suggests that the exclusion process is triggered by some event during a trial. The results, interpreted within the framework of a summed similarity model for visual recognition, suggest that exclusion operates after considerable visual processing of the to-be-excluded item.     

Out of sight,out of mind: The attentional blink can eliminate synaesthetic colours

Mechanisms of selective attention exert a powerful influence on visual perception. We examined whether attentional selection is necessary for generation of the vivid colours experienced by individuals with grapheme-colour synaesthesia. Twelve synaesthetes and matched controls viewed rapid serial displays of nonsense characters within which were embedded an oriented grating (T1) and a letter-prime (T2), forming a modified attentional blink (AB) task. At the end of the stream a coloured probe appeared that was either congruent or incongruent with the synaesthetic colour elicited by the letter-prime. When the prime was attended, synaesthetes showed a reliable effect of prime-probe congruency. In contrast, when the prime appeared at 350 ms following T1 (during the AB), the congruency effect was eliminated. Our findings suggest that focused attention is crucial for inducing letters to elicit colours in synaesthesia.     

Out of sight,out of mind: Occlusion and the accessibility of information in narrative comprehension

Do readers encode the perceptual perspectives of characters during narrative comprehension? To address this question, we conducted two experiments using stories that sometimes described situations in which certain information was occluded from the protagonists’ views. We generated two related hypotheses concerning the potential impact of occlusion events on text representations. One, theevent boundary hypothesis, suggested that any salient narrative event would reduce the accessibility of prior story information. The second, theperceptual availability hypothesis, suggested that accessibility would decrease most for information no longer visible to story protagonists. In Experiment 1, the participants were slowest to respond to verification questions that asked about occluded information. In Experiment 2, we demonstrated that this effect did not extend to other, nonoccluded information. These results suggest that readers encode text information from the perceptual perspective of story protagonists. This is consistent with recent perceptual symbol views of language comprehension.     

Out of sight,out of mind: Occlusion and eye closure destabilize moving bistable structure-from-motion displays

Our brain constantly tries to anticipate the future by using a variety of memory mechanisms. Interestingly, studies using the intermittent presentation of multistable displays have shown little perceptual persistence for interruptions longer than a few hundred milliseconds. Here we examined whether we can facilitate the perceptual stability of bistable displays following a period of invisibility by employing a physically plausible and ecologically valid occlusion event sequence, as opposed to the typical intermittent presentation, with sudden onsets and offsets. To this end, we presented a bistable rotating structure-from-motion display that was moving along a linear horizontal trajectory on the screen and either was temporarily occluded by another object (a cardboard strip in Exp. 1, a computer-generated image in Exp. 2) or became invisible due to eye closure (Exp. 3). We report that a bistable rotation direction reliably persisted following occlusion or interruption only (1) if the pre- and postinterruption locations overlapped spatially (an occluder with apertures in Exp. 2 or brief, spontaneous blinks in Exp. 3) or (2) if an object’s size allowed for the efficient grouping of dots on both sides of the occluding object (large objects in Exp. 1). In contrast, we observed no persistence whenever the pre- and postinterruption locations were nonoverlapping (large solid occluding objects in Exps. 1 and 2 and long, prompted blinks in Exp. 3). We report that the bistable rotation direction of a moving object persisted only for spatially overlapping neural representations, and that persistence was not facilitated by a physically plausible and ecologically valid occlusion event.     

Binocular rivalry and semantic processing: out of sight, out of mind

Previous studies of binocular rivalry have shown that some aspects of a phenomenally suppressed stimulus remain available for visual analysis. The question remains, however, whether this analysis extends to the case of semantic information. This experiment examines that question using a semantic-priming paradigm in which prime words were briefly flashed to an eye during either dominance or suppression phases of binocular rivalry. Reaction times on a lexical-decision task were significantly shortened (the semantic-priming effect) only when prime words were presented to an eye during dominance; suppression acted to impair word recognition and to eliminate semantic priming. These results are inconsistent with certain cognitive models of binocular rivalry.     

Out of sight, out of mind: the rarity of assessing and reporting participants' visual abilities when studying perception of linguistic stimuli

Variations in visual abilities are widespread in the adult population and have profound effects on processing linguistic stimuli (text, words, letters). However, a review of articles (1442) investigating the processing of visually presented linguistic stimuli by non-clinical adult participants, published in 2000-2010 in five leading journals (Journal of Experimental Psychology: Human Perception and Performance; Journal of Experimental Psychology: Learning, Memory, and Cognition; Memory & Cognition; Perception & Psychophysics/Attention, Perception, & Psychophysics; and Perception), showed that the majority of articles (73.5%) made no mention of participants' visual abilities (62.1%) or relied merely on participants' self-report (11.4%). 25.2% reported participants' visual abilities with no assessment, and only 1.2% reported participants' visual abilities following objective assessment; the highest percentage of articles within this laudable minority was in Perception. The indications are that objective visual assessments in studies of visually presented linguistic stimuli are rare and greater use would facilitate better understanding of the visuo-cognitive processes involved.     

Alcohol impairs visual presence/absence detection more for females than for males

Ninety subjects (45 males, 45 females) were given 0.0, 0.5, or 1.0 ml/kg body weight of 190-proof ethanol and tested for chance-level presence/absence detection thresholds with energy-masked presentations of traffic signs and blank inputs. Alcohol produced higher blood alcohol concentration (BAC) levels, and higher detection threshold durations, for females than for males. These results indicate that alcohol influences precortical visual processing and that the influence is greater for females than for males. The higher bioavailability of alcohol in women is likely due to less gastric oxidation of ethanol in women than in men.     

In sight, out of mind: the role of eye movements in the rapid resumption of visual search

Three experiments investigated the role of eye movements in the rapid resumption of an interrupted search. Passive monitoring of eye position in Experiment 1 showed that rapid resumption was associated with a short distance between the eye and the target on the next-to-last look before target detection. Experiments 2 and 3 used two different methods for presenting the target to the point of eye fixation on some trials. If eye position alone is predictive, rapid resumption should increase when the target is near fixation. The results showed that gaze-contingent targets increased overall search success, but that the proportion of rapid responses decreased dramatically. We conclude that rather than depending on a high-quality single look at a search target, rapid resumption of search depends on two glances; a first glance in which a hypothesis is formed, and a second glance in which the hypothesis is confirmed.     

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.     

Clinical judgment in forensic neuropsychology: A comment on the risks of claiming more than can be delivered

There is a vast and growing literature in psychology demonstrating the general limits of human judgment and clinical inference. These findings clearly apply in the new specialty of clinical neuropsychology, and there is little empirical research to support the widespread belief that judgmental accuracy correlates substantially with experience, professional stature, or reputation as a neuropsychologist. However, the demand characteristics of expert testimony in the forensic arena may encourage individual neuropsychologists to state or intimate that they have unique or special expertise in understanding brain-behavior relationships, or in predicting outcomes following cerebral insult or injury. These claims will be increasingly difficult to substantiate as attorneys become more conversant with the literature on human judgment.     

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.     

Out of one's mind: a study of involuntary semantic memories

The study of memories that pop into one's mind without any conscious attempt to retrieve them began only recently. While there are some studies on involuntary autobiographical memories (e.g., ) research on involuntary semantic memories or mind-popping is virtually non-existent. The latter is defined as an involuntary conscious occurrence of brief items of one's network of semantic knowledge. The recall of these items (e.g., a word, a name, a tune) is not accompanied by additional contextual information and/or involvement of self-a standard feature of involuntary autobiographical memories. The paper reports several diary and questionnaire studies which looked into the nature and frequency of occurrence of these memories. The data show that people do experience involuntary semantic memories which tend to occur without any apparent cues while being engaged in relatively automatic activities. Possible mechanisms of involuntary semantic memories are discussed (e.g., very long-term priming), and the results of the study provide information on the possible duration of the priming effects in everyday life. Related theoretical and methodological issues and future avenues of research in this neglected area are outlined.     

Intentional inferences are not more likely than unintentional ones: some evidence against the intentionality bias hypothesis

We conducted a study to test the hypothesis that inferences about intentionality are biased toward an intentional interpretation. Contrary to previous research, participants were no more likely to judge ambiguous actions as intentional in a speeded compared to an unspeeded condition. Further, participants were faster to respond and more consistent in responding to unintentional rather than intentional actions.     

More than a body: mind perception and the nature of objectification

According to models of objectification, viewing someone as a body induces de-mentalization, stripping away their psychological traits. Here evidence is presented for an alternative account, where a body focus does not diminish the attribution of all mental capacities but, instead, leads perceivers to infer a different kind of mind. Drawing on the distinction in mind perception between agency and experience, it is found that focusing on someone's body reduces perceptions of agency (self-control and action) but increases perceptions of experience (emotion and sensation). These effects were found when comparing targets represented by both revealing versus nonrevealing pictures (Experiments 1, 3, and 4) or by simply directing attention toward physical characteristics (Experiment 2). The effect of a body focus on mind perception also influenced moral intuitions, with those represented as a body seen to be less morally responsible (i.e., lesser moral agents) but more sensitive to harm (i.e., greater moral patients; Experiments 5 and 6). These effects suggest that a body focus does not cause objectification per se but, instead, leads to a redistribution of perceived mind.     

Domain-specificity and theory of mind: evaluating neuropsychological evidence

Humans' unique aptitude for reasoning about mental states, known as Theory of Mind (ToM), can help explain the unique character of human communication and social interaction. ToM has been studied extensively in children, but there is no clear account of the cognitive basis of ToM in adults. Evidence from functional imaging and neuropsychology is beginning to address this surprising gap in our understanding, and this evidence is often thought to favour a domain-specific or modular architecture for ToM. We present a systematic approach to this issue for the paradigmatic case of belief reasoning, and argue that neuropsychological data provide no clear evidence for domain-specificity or modularity. Progress in understanding ToM requires new tasks that isolate potentially distinct components of this complex ability.     

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.