Distributed recognition of natural songs by European starlings

Individual vocal recognition behaviors in songbirds provide an excellent framework for the investigation of comparative psychological and neurobiological mechanisms that support the perception and cognition of complex acoustic communication signals. To this end, the complex songs of European starlings have been studied extensively. Yet, several basic parameters of starling individual vocal recognition have not been assessed. Here we investigate the temporal extent of song information acquired by starlings during vocal recognition learning. We trained two groups of starlings using standard operant conditioning techniques to recognize several songs from two conspecific male singers. In the first experiment we tested their ability to maintain accurate recognition when presented with (1) random sequences of 1–12 motifs (stereotyped song components) drawn from the training songs, and (2) 0.1–12-s excerpts of continuous song drawn from the training songs. We found that song recognition improved monotonically as more vocal material is provided. In the second experiment, we systematically substituted continuous, varying length regions of white noise for portions of the training songs and again examined recognition accuracy. Recognition remained above chance levels for all noise substitutions tested (up to 91% of the training stimulus) although all but the smallest substitutions led to some decrement in song recognition. Overall, above chance recognition could be obtained with surprisingly few motifs, short excerpts of song, and in the absence of large portions of the training songs. These results suggest that starlings acquire a representation of song during individual vocal recognition learning that is robust to perturbations and distributed broadly over large portions of these complex acoustic sequences.     

Underestimating numerosity of items in visual search tasks

Previous research on numerosity judgments addressed attended items, while the present research addresses underestimation for unattended items in visual search tasks. One potential cause of underestimation for unattended items is that estimates of quantity may depend on viewing a large portion of the display within foveal vision. Another theory follows from the occupancy model: estimating quantity of items in greater proximity to one another increases the likelihood of an underestimation error. Three experimental manipulations addressed aspects of underestimation for unattended items: the size of the distracters, the distance of the target from fixation, and whether items were clustered together. Results suggested that the underestimation effect for unattended items was best explained within a Gestalt grouping framework.     

Nested Logit Models for Multiple-Choice Item Response Data

Nested logit item response models for multiple-choice data are presented. Relative to previous models, the new models are suggested to provide a better approximation to multiple-choice items where the application of a solution strategy precedes consideration of response options. In practice, the models also accommodate collapsibility across all distractor categories, making it easier to allow decisions about including distractor information to occur on an item-by-item or application-by-application basis without altering the statistical form of the correct response curves. Marginal maximum likelihood estimation algorithms for the models are presented along with simulation and real data analyses.     

Extending Free Pregroups with Lower Bounds

In this paper, we propose an extension of free pregroups with lower bounds on sets of pregroup elements. Pregroup grammars based on such pregroups provide a kind of an algebraic counterpart to universal quantification over type-variables. In particular, we show how our pregroup extensions can be used for pregroup grammars expressing natural-language coordination and extraction.     

Selective exposure: The impact of framing information search instructions as gains and losses

Previous research has found that people prefer information that supports rather than conflicts with their decisions (selective exposure). In the present paper, we investigated whether selective exposure was influenced by the method of information collection. Based on Prospect Theory we hypothesized that the method of selection (MOS), where simply selected pieces of information are considered, would lead to a higher selective exposure compared to the method of elimination (MOE), where pieces of information are rejected and the remaining pieces of information are considered. In fact, we found that participants collected information more selectively when they were instructed to use the MOS compared to the MOE. Copyright © 2009 John Wiley & Sons, Ltd.     

Start-up Rhetoric in Eight Speeches of Barack Obama

Our purpose in the following was to investigate the start-up rhetoric employed by U.S. President Barack Obama in his speeches. The initial 5 min from eight of his speeches from May to September of 2009 were selected for their variety of setting, audience, theme, and purpose. It was generally hypothesized that Barack Obama, widely recognized for the excellence of his rhetorical performance, would pursue both constant and variable strategies in his effort to establish contact with his audience. More specifically, it was hypothesized that the make-up of the audience—primarily native or non-native speakers of English—would be a prominent independent variable. A number of temporal and verbal measures were used as dependent variables. Variations were evident in mean length in syllables and duration in seconds of utterances (articulatory phrases), articulation rate in syllables per second of ontime, mean duration of silent pauses in seconds, and frequency of fillers, hesitations, colloquial words and phrases, introductory phrases, and 1st person singular pronominals. Results indicated that formality versus informality of the setting and presence or absence of a teleprompter were more prominent than native versus non-native audiences. Our analyses confirm Obama’s skillfulness in challenging and variable settings and clearly detect orderliness and scientific generalizability in language use. The concept of orality/literacy provides a theoretical background and emphasizes dialogical interaction of audience and speaker.     

Developmental Precursors of Moral Disengagement and the Role of Moral Disengagement in the Development of Antisocial Behavior

The purpose of the study was to advance our understanding of the developmental precursors of Moral Disengagement (MD) and the role of MD in the development of antisocial behavior from early risk among an ethnically diverse sample of 187 low-income boys followed prospectively from ages 1.5 to 17. Results indicated associations between early rejecting parenting, neighborhood impoverishment, and child empathy and later MD. The link between some of these early constructs and later antisocial behavior was mediated by MD. Finally, in an exploratory path model both MD and biases in social information processing were found to mediate separate paths from early risk factors to later antisocial behavior. Results were partially consistent with the notion that adolescent MD was predicted by a combination of early family, neighborhood, and child risk factors, and that MD may be a mechanism underlying some boys’ risk of antisocial behavior.     

Heating up or cooling up the brain? MEG evidence that phrasal verbs are lexical units

There is a considerable linguistic debate on whether phrasal verbs (e.g., turn up, break down) are processed as two separate words connected by a syntactic rule or whether they form a single lexical unit. Moreover, views differ on whether meaning (transparency vs. opacity) plays a role in determining their syntactically-connected or lexical status. As linguistic arguments could not settle these issues, we used neurophysiological brain imaging to address them. Applying a multi-feature Mismatch Negativity (MMN) design with subjects instructed to ignore speech stimuli, we recorded magnetic brain responses to particles (up, down) auditorily presented as infrequent "deviant" stimuli in the context of frequently occurring verb "standard" stimuli. Already at latencies below 200ms, magnetic brain responses were larger to particles appearing in existing phrasal verbs (e.g. rise up) than to particles appearing in non-existing combinations (e.g. ?fall up), regardless of whether particles carried a literal or metaphorical sense (e.g. rise up, heat up). Previous research found an enhanced MMN response to morphemes in existing (as opposed to non-existing) words but a reduced MMN to words in grammatically acceptable (as opposed to unacceptable) combinations. The increased brain activation to particles in real phrasal verbs reported here is consistent with the lexical enhancement but inconsistent with the syntactic reduction of the MMN, thus providing neurophysiological support that a congruent verb-particle sequence is not assembled syntactically but rather accessed as a single lexical chunk.