What time travelers cannot not do (but are responsible for anyway)

The Principle of Alternative Possibilities is the intuitive idea that someone is morally responsible for an action only if she could have done otherwise. Harry Frankfurt has famously presented putative counterexamples to this intuitive principle. In this paper, I formulate a simple version of the Principle of Alternative Possibilities that invokes a course-grained notion of actions. After warming up with a Frankfurt-Style Counterexample to this principle, I introduce a new kind of counterexample based on the possibility of time travel. At the end of the paper, I formulate a more sophisticated version of the Principle of Alternative Possibilities that invokes a certain fine grained notion of actions. I then explain how this new kind of counterexample can be augmented to show that even the more sophisticated principle is false.     

What preschool children do and do not do with ungrammatical word orders

Akhtar [J. Child Lang. 26 (1999) 339.] found that when 4-year-old English-speaking children hear novel verbs in transitive utterances with ungrammatical word orders (e.g., Elmo the tree meeked), they correct them to canonical SVO order almost all of the time. However, when 3-year-olds and older 2-year-olds hear these same utterances, they waver between correcting and using the ungrammatical ordering. In the current study, we adapted this task for children at 2;4, using an intransitive construction. The major finding was that children corrected the noncanonical word order less than half as often as Akhtar's 2-year-old subjects who were approximately 4 months older. At the same time, however, children showed in several ways that they had some implicit understanding of canonical SV order; for example, they used the novel verb which they heard used in grammatical word order more often than the novel verb which they heard in ungrammatical word order, and they consistently used pronouns and the progressive –s auxiliary in appropriate ways. The current findings thus contribute to a growing body of theory and research suggesting that the ontogenetic emergence of linguistic categories and schemas is a gradual process, as is the emergence of categories in other domains of cognitive development.     

What neuroimaging and brain localization can do, cannot do and should not do for social psychology

Interest in bridging social psychology and neuroscience has seen a significant upsurge. Much of this interest has centered on brain localization--the attempt to relate psychological events to locations of brain events. Although many articles have sought to localize brain activity that supports social behavior, scant attention has been paid to the specific methods to be used in integrating brain localization data into psychological theory. The authors describe 4 strategies psychologists can use to integrate brain localization data and psychological theory, and they consider whether social psychology presents special considerations in the use of these strategies. They conclude that brain localization offers a useful tool for some but not all problems in social psychology, and they discuss the types of problems for which it may and may not prove useful.     

What mediation analysis can (not) do

The present article is concerned with a common misunderstanding in the interpretation of statistical mediation analyses. These procedures can be sensibly used to examine the degree to which a third variable (Z) accounts for the influence of an independent (X) on a dependent variable (Y) conditional on the assumption that Z actually is a mediator. However, conversely, a significant mediation analysis result does not prove that Z is a mediator. This obvious but often neglected insight is substantiated in a simulation study. Using different causal models for generating Z (genuine mediator, spurious mediator, correlate of the dependent measure, manipulation check) it is shown that significant mediation tests do not allow researchers to identify unique mediators, or to distinguish between alternative causal models. This basic insight, although well understood by experts in statistics, is persistently ignored in the empirical literature and in the reviewing process of even the most selective journals.     

Negative numbers eliminate,but do not reverse,the attentional SNARC effect

Three experiments are reported examining whether the presentation of irrelevant negative numbers at central fixation interacts with attentional orienting beyond fixation. It has been previously shown that number perception influences spatial attention, with the presentation of spatially nonpredictive numbers resulting in the allocation of attention to the left when the number is low (e.g., 1 or 2) and to the right when the number is high (e.g., 8 or 9). In the present experiment, it is examined whether this attentional spatial numerical association of response codes (SNARC) effect is influenced by the presentation of negative numbers, which should have spatial properties that are in direct opposition to their positive counterparts (e.g., −1 or −2 would be considered high numbers relative to −8 or −9, which would be considered low numbers). Though the presentation of negative numbers does not lead to a reversal of the attentional SNARC effect, it does lead to an elimination of the effect, providing insight into how the attentional SNARC effect develops.     

Human ostensive signals do not enhance gaze following in chimpanzees,but do enhance object-oriented attention

The previous studies have shown that human infants and domestic dogs follow the gaze of a human agent only when the agent has addressed them ostensively—e.g., by making eye contact, or calling their name. This evidence is interpreted as showing that they expect ostensive signals to precede referential information. The present study tested chimpanzees, one of the closest relatives to humans, in a series of eye-tracking experiments using an experimental design adapted from these previous studies. In the ostension conditions, a human actor made eye contact, called the participant’s name, and then looked at one of two objects. In the control conditions, a salient cue, which differed in each experiment (a colorful object, the actor’s nodding, or an eating action), attracted participants’ attention to the actor’s face, and then the actor looked at the object. Overall, chimpanzees followed the actor’s gaze to the cued object in both ostension and control conditions, and the ostensive signals did not enhance gaze following more than the control attention-getters. However, the ostensive signals enhanced subsequent attention to both target and distractor objects (but not to the actor’s face) more strongly than the control attention-getters—especially in the chimpanzees who had a close relationship with human caregivers. We interpret this as showing that chimpanzees have a simple form of communicative expectations on the basis of ostensive signals, but unlike human infants and dogs, they do not subsequently use the experimenter’s gaze to infer the intended referent. These results may reflect a limitation of non-domesticated species for interpreting humans’ ostensive signals in inter-species communication.     

Making related errors facilitates learning,but learners do not know it

Producing an error, so long as it is followed by corrective feedback, has been shown to result in better retention of the correct answers than does simply studying the correct answers from the outset. The reasons for this surprising finding, however, have not been investigated. Our hypothesis was that the effect might occur only when the errors produced were related to the targeted correct response. In Experiment 1, participants studied either related or unrelated word pairs, manipulated between participants. Participants either were given the cue and target to study for 5 or 10 s or generated an error in response to the cue for the first 5 s before receiving the correct answer for the final 5 s. When the cues and targets were related, error-generation led to the highest correct retention. However, consistent with the hypothesis, no benefit was derived from generating an error when the cue and target were unrelated. Latent semantic analysis revealed that the errors generated in the related condition were related to the target, whereas they were not related to the target in the unrelated condition. Experiment 2 replicated these findings in a within-participants design. We found, additionally, that people did not know that generating an error enhanced memory, even after they had just completed the task that produced substantial benefits.     

What young children do and do not know about the spelling of inflections and derivations

Morphemes have a powerful impact on the spellings of words in English. We report on two experiments examining young children's knowledge of the effect of suffix morphemes on spelling. In Experiment 1, 5- to 8-year-olds demonstrated awareness of the role of inflections, but not derivations in spelling. Experiment 2 examined whether children might show an understanding of the impact of derivations on spelling when they are provided with the specific spelling pattern. There was support for this idea; 7- to 10-year-old children took advantage of the derivations that were given to spell other derivations, but not the endings of control words. The results of these experiments suggest that young children are aware of the role that suffixes play in determining spelling, but that there are limits, such as those imposed by spelling difficulty, that constrain the execution of this knowledge. These findings provide new insights into current theoretical debates on spelling development.     

Signals of threat do not capture, but prioritize, attention: a conditioning approach

Research suggests that threatening information captures attention more rapidly than neutral information. However, in most studies threat stimuli differ perceptually from neutral stimuli and are instrumental to perform the task, leaving the question unanswered whether threat is sufficient to capture attention. In experiment 1, we designed a visual search task with stimuli of equal salience (colored circles) that have the potential to lead to efficient search (10 ms/item). In experiment 2, one of the colors (conditioned stimulus, CS+) was made threatening by means of fear conditioning. Participants responded to a target presented in one of the circles. Overall, the search was faster on congruent trials (where the target was presented in the CS+) than on baseline trials (where the CS + was absent). Furthermore, the search was slower on incongruent trials (where the target was presented in another color than the CS+) than on baseline trials. The search on congruent trials was affected by set size (90 ms/item), but to a lesser extent than on baseline trials (105 ms/item). We conclude that threat prioritizes, but does not capture attention.     

What concepts do

This paper identifies and criticizes a line of reasoning that has played a substantial role in the widespread rejection of the view that Fodor has dubbed “Concept Atomism”. The line of reasoning is not only fallacious, but its application in the present case rests on a misconception about the explanatory potential of Concept Atomism. This diagnosis suggests the possibility of a new polemical strategy in support of Concept Atomism. The new strategy is more comprehensive than that which defenders of the view, namely Fodor, have employed.     

Kanizsa-type subjective contours do not guide attentional deployment in visual search but line termination contours do

We used visual search to explore whether attention could be guided by Kanizsa-type subjective contours and by subjective contours induced by line ends. Unlike in previous experiments, we compared search performance with subjective contours against performance with real, luminance contours, and we had observers search for orientations or shapes produced by subjective contours, rather than searching for the presence of the contours themselves. Visual search for one orientation or shape among distractors of another orientation or shape was efficient when the items were defined by luminance contours. Search was much less efficient among items defined by Kanizsa-type subjective contours. Search remained efficient when the items were defined by subjective contours induced by line ends. The difference between Kanizsa-type subjective contour and subjective contours induced by line ends is consistent with physiological evidence suggesting that the brain mechanisms underlying the perception of these two kinds of subjective contours may be different.     

What bilateral displays do

Bilateral presentations of stimuli produce asymmetries larger than those of unilateral presentations, an effect that exists across modalities. In the case of visual field differences at least 13 hypotheses of the effect have been proposed, 6 of which suggest that some form of hemispheric interaction is responsible for the bilateral advantage. Previous research has eliminated all 7 noninteraction hypotheses, has supported the class of hemispheric interaction mechanisms, and has ruled out two specific instances of the latter. Here four experiments test the remaining hypotheses. The results support the homolog activation hypothesis, which states that bilateral stimulation by similar stimuli activates homologous areas of the two hemispheres, disrupting communication between the areas. The other hypotheses were eliminated.     

What we can do

Philosophical Studies - Plural first-person pronouns have often been ignored in the literature on indexicals and pronouns. The assumption seems to be that we is just the plural of I. So, we can...     

Explicit warnings reduce but do not eliminate the continued influence of misinformation

Information that initially is presumed to be correct, but that is later retracted or corrected, often continues to influence memory and reasoning. This occurs even if the retraction itself is well remembered. The present study investigated whether the continued influence of misinformation can be reduced by explicitly warning people at the outset that they may be misled. A specific warning— giving detailed information about the continued influence effect (CIE)—succeeded in reducing the continued reliance on outdated information but did not eliminate it. A more general warning—reminding people that facts are not always properly checked before information is disseminated—was even less effective. In an additional experiment, a specific warning was combined with the provision of a plausible alternative explanation for the retracted information. This combined manipulation further reduced the CIE but still failed to eliminate it altogether.     

Forgotten but not gone: context effects on recognition do not require explicit memory for context

Context effects on recognition memory provide an important indirect assay of associative learning and source memory. Neuropsychological studies have indicated that such context effects may obtain even if the contexts themselves are not remembered--for example, in individuals impaired on direct tests of memory for contextual information. In contrast, a recent study indicated that the effects of temporal context reinstatement on visual recognition obtain only when the contextual information itself was explicitly recollected. Here we report that the effects of reinstatement of spatial-simultaneous context on visual object recognition memory obtain irrespective of whether those context stimuli are explicitly recognized. We suggest that spatial-simultaneous context effects might be based on ensemble unitization of target and context stimuli at encoding, whereas temporal context effects may require recollective processes.     

Forgotten but not gone: Context effects on recognition do not require explicit memory for context

Context effects on recognition memory provide an important indirect assay of associative learning and source memory. Neuropsychological studies have indicated that such context effects may obtain even if the contexts themselves are not remembered—for example, in individuals impaired on direct tests of memory for contextual information. In contrast, a recent study indicated that the effects of temporal context reinstatement on visual recognition obtain only when the contextual information itself was explicitly recollected. Here we report that the effects of reinstatement of spatial-simultaneous context on visual object recognition memory obtain irrespective of whether those context stimuli are explicitly recognized. We suggest that spatial-simultaneous context effects might be based on ensemble unitization of target and context stimuli at encoding, whereas temporal context effects may require recollective processes.