Hearing in large mammals: sound-localization acuity in cattle (Bos taurus) and goats (Capra hircus).

Sound localization acuity of 3 cattle (Bos taurus) and 2 goats (Capra hircus) was determined for brief complex sounds in a two-choice procedure. Thresholds around the median sagittal plane averaged 30 degrees and 18 degrees, respectively. For comparison, thresholds were obtained in the same test apparatus for humans (0.8 degrees) and a dog (8 degrees). Although the relatively poor acuity of cattle and goats compared with most mammals comes as some surprise, given their large interaural distances and the large binaural locus cues available to them, it is not unexpected when other factors are considered. Like other poor localizers (both domesticated and nondomesticated), cattle and goats are prey species with their best vision directed throughout nearly the entire horizon. In contrast to mammals with very narrow foveal fields, they may not need very accurate locus information from their auditory systems to direct their gaze to a sound source.     

Going As Far As We Can Go: The Jesus Proposal For Stretching Genes and Cultures

The Christian perspective on morality is examined under the rubric of "being like Jesus" and the "Jesus proposal for morality." The Peace People of Northern Ireland are examples of this proposal. Among the features of Christian moral thinking that are emphasized are: Jesus' concern for the future, the transformation that the future requires, human nature interpreted in terms of how it can undergo transformation, and self-giving love as the core of this transformation. Attention is given to the ways in which Jesus both radicalized and relativized the moral conventions of his day. Dialogue with sociobology comes into play when Jesus is viewed as a proposal for cultural evolution and a kind of biocultural mutation. Gerd Theissen's scholarship on Jesus' moral perspectives is given special attention.     

Sound localization in an Old-World fruit bat (Rousettus aegyptiacus): acuity, use of binaural cues, and relationship to vision.

The passive sound-localization acuity of Egyptian fruit bats (Rousettus aegyptiacus) was determined using a conditioned-avoidance procedure. The mean minimum audible angle for left-right discrimination for 3 bats was 11.6 degrees--very near the mean for terrestrial mammals. The bats also were able to localize low- and high-frequency pure tones, indicating that they can use both binaural phase-difference and binaural intensity-difference cues to localize sound. Moreover, they were able to use the binaural phase-difference cue up to at least 5.6 kHz, which is higher than other mammals yet tested. The width of the Egyptian fruit bats' field of best vision was 27 degrees. This value is consistent with the hypothesis that the role of passive sound localization is to direct the eyes for visual scrutiny of sound sources. Thus, the passive localization abilities of these echolocating megachiropteran fruit bats do not deviate from the patterns established for nonecholocating mammals.     

An automated sound-localization chamber

A completely automated free-field sound-localization apparatus is described along with a behavioral technique that provides several advantages over previously available methods. With the apparatus, the ability to localize the source of a sound has been tested in a wide variety of mammals including cats, rats, squirrel monkeys, hedgehogs, and tree shews.     

Support for context effects on segmentation and segments depends on the context

Listeners must adapt to differences in speech rate across talkers and situations. Speech rate adaptation effects are strong for adjacent syllables (i.e., proximal syllables). For studies that have assessed adaptation effects on speech rate information more than one syllable removed from a point of ambiguity in speech (i.e., distal syllables), the difference in strength between different types of ambiguity is stark. Studies of word segmentation have shown large shifts in perception as a result of distal rate manipulations, while studies of segmental perception have shown only weak, or even nonexistent, effects. However, no study has standardized methods and materials to study context effects for both types of ambiguity simultaneously. Here, a set of sentences was created that differed as minimally as possible except for whether the sentences were ambiguous to the voicing of a consonant or ambiguous to the location of a word boundary. The sentences were then rate-modified to slow down the distal context speech rate to various extents, dependent on three different definitions of distal context that were adapted from previous experiments, along with a manipulation of proximal context to assess whether proximal effects were comparable across ambiguity types. The results indicate that the definition of distal influenced the extent of distal rate effects strongly for both segments and segmentation. They also establish the presence of distal rate effects on word-final segments for the first time. These results were replicated, with some caveats regarding the perception of individual segments, in an Internet-based sample recruited from Mechanical Turk.     

The MR2: A multi-racial,mega-resolution database of facial stimuli

Faces impart exhaustive information about their bearers, and are widely used as stimuli in psychological research. Yet many extant facial stimulus sets have substantially less detail than faces encountered in real life. In this paper, we describe a new database of facial stimuli, the Multi-Racial Mega-Resolution database (MR2). The MR2 includes 74 extremely high resolution images of European, African, and East Asian faces. This database provides a high-quality, diverse, naturalistic, and well-controlled facial image set for use in research. The MR2 is available under a Creative Commons license, and may be accessed online.     

Incremental Validity of Perceived Control Dimensions in the Differential Prediction of Interpretive Biases for Threat

This study evaluated whether a diminished perception of control over environmental and interoceptive events differentially predicted interpretive biases for threat for ambiguous scenarios. The sample had 95 participants without a history of psychopathology. Results indicated that the internal dimension of the Anxiety Control Questionnaire (ACQ; R. M. Rapee, M. G. Craske, T. A. Brown, & D. H. Barlow, 1996) was predictive of interpretive biases for internal scenarios above and beyond demographic variables, subclinical panic attack history, and state anxiety; the external control subscale of the ACQ also was predictive of internal rank-ordered responses. The ACQ external dimension was predictive of interpretive responses for external scenarios beyond the effects accounted for by the other predictor variables, including perceived control for internal events. These findings provide initial correlational evidence consistent with cognitive–behavioral accounts of panic disorder that posit a perceived lack of control over aversive events may exacerbate an interpretive bias for threat.     

A two-choice sound localization procedure for detecting lateralized tinnitus in animals

Rats were trained in a two-choice procedure to respond in the direction of left and right sounds. Silent trials, on which no sound was presented and for which the animals received no feedback, were interspersed among the sound trials to determine each animal’s natural side preference. Following training, the rats were exposed to a loud tone in the ear opposite their side preference. A shift in responding on the silent trials to the side of the exposed ear indicated that the animals were hearing a sound in that ear (i.e., tinnitus). Simulating lateralized tinnitus by presenting a low-level, continuous sound on one side also caused the rats to shift their responding on the silent trials to that side. Sham exposures indicated that halothane/nitrous oxide anesthesia could reinstate tinnitus in animals that had previously tested positive for it. Exposing rats to loud tones of various frequencies indicated that frequencies near the limits of the rat’s hearing range were less likely to cause tinnitus than tones in the midrange.     

Traffic crash involvement: experiential driving knowledge and stressful contextual antecedents

Researchers have rarely examined stressful environments and psychological characteristics as predictors of driving behavior in the same study. The authors hypothesized that (a) safer drivers more accurately assess physical and emotional traffic hazards and (b) stress and emotional states elevate crash risk. The hypotheses were evaluated with procedural and declarative tacit driving knowledge tests requiring assessment of emotional and contextual hazards and with accident reports describing crash antecedents, including stressful events and environmental conditions. Analyses identified separate driving knowledge factors corresponding to emotional and contextual hazards that were significantly related to the crash criteria. Accident report analyses show that stress significantly elevates at-fault crash risk. The results demonstrate the importance of experiential knowledge acquired without instruction (procedural or tacit knowledge) and provide safety recommendations.