Interactive use of sign language by cross-fostered chimpanzees (Pan troglodytes)

Cross-fostered as infants in Reno, Nevada, chimpanzees (Pan troglodytes) Washoe, Moja, Tatu, and Dar freely converse in signs of American Sign Language with each other as well as with humans in Ellensburg, Washington. In this experiment, a human interlocutor waited for a chimpanzee to initiate conversations with her and then responded with 1 of 4 types of probes: general requests for more information, on-topic questions, off-topic questions, or negative statements. The responses of the chimpanzees to the probes depended on the type of probe and the particular signs in the probes. They reiterated, adjusted, and shifted the signs in their utterances in conversationally appropriate rejoinders. Their reactions to and interactions with a conversational partner resembled patterns of conversation found in similar studies of human children.     

Is there a general factor in ratings of job performance? A meta-analytic framework for disentangling substantive and error influences

A database integrating 90 years of empirical studies reporting intercorrelations among rated job performance dimensions was used to test the hypothesis of a general factor in job performance. After controlling for halo error and 3 other sources of measurement error, there remained a general factor in job performance ratings at the construct level accounting for 60% of total variance. Construct-level correlations among rated dimensions of job performance were substantially inflated by halo for both supervisory (33%) and peer (63%) intrarater correlations. These findings have important implications for the measurement of job performance and for theories of job performance.     

An interval size illusion: the influence of timbre on the perceived size of melodic intervals

In four experiments, we investigated the influence of timbre on perceived interval size. In Experiment 1, musically untrained participants heard two successive tones and rated the pitch distance between them. Tones were separated by six or seven semitones and varied in timbre. Pitch changes were accompanied by a congruent timbre change (e.g., ascending interval involving a shift from a dull to a bright timbre), an incongruent timbre change (e.g., ascending interval involving a shift from a bright to a dull timbre), or no timbre change. Ratings of interval size were strongly influenced by timbre. The six-semitone interval with a congruent timbre change was perceived to be larger than the seven-semitone interval with an incongruent timbre change (interval illusion). Experiment 2 revealed similar effects for musically trained participants. In Experiment 3, participants compared the size of two intervals presented one after the other. Effects of timbre were again observed, including evidence of an interval illusion. Experiment 4 confirmed that timbre manipulations did not distort the perceived pitch of tones. Changes in timbre can expand or contract the perceived size of intervals without distorting individual pitches. We discuss processes underlying interval size perception and their relation to pitch perception mechanisms.     

Perception of visual speed while moving

During self-motion, the world normally appears stationary. In part, this may be due to reductions in visual motion signals during self-motion. In 8 experiments, the authors used magnitude estimation to characterize changes in visual speed perception as a result of biomechanical self-motion alone (treadmill walking), physical translation alone (passive transport), and both biomechanical self-motion and physical translation together (walking). Their results show that each factor alone produces subtractive reductions in visual speed but that subtraction is greatest with both factors together, approximating the sum of the 2 separately. The similarity of results for biomechanical and passive self-motion support H. B. Barlow's (1990) inhibition theory of sensory correlation as a mechanism for implementing H. Wallach's (1987) compensation for self-motion.     

Victim and perpetrator accounts of interpersonal transgressions: self-serving or relationship-serving biases?

Two studies investigated perpetrator and victim biases in reported transgressions. Study 1 showed that in nonromantic relationships, perpetrators were more likely than victims to emphasize details that minimized their transgressions, whereas victims were more likely to exaggerate the severity of the event. Study 2 examined these perspective-related differences in romantic relationships and their relationship to forgiveness. Although victims were less likely than perpetrators to include features that minimized the event, they were no more likely to include features that magnified the event; individuals in highly satisfying relationships were less likely to exhibit self-serving biases than were individuals in less satisfying relationships. The data also were consistent with a causal sequence in which positive relationship quality led to more benign interpretations of a transgression, which in turn, promoted forgiveness.     

Predicting without modeling: a critique of Trabasso and Bartolone (2003)

T. Trabasso and J. Bartolone (2003) used a computational model of narrative text comprehension to account for empirical findings. The authors show that the same predictions are obtained without running the model. This is caused by the model's computational setup, which leaves most of the model's input unchanged.     

An fMRI study on conceptual, grammatical, and morpho-phonological processing

The aim of the present study was to determine whether processing of syntactic word information (lemma) is subserved by the same neural substrate as processing of conceptual or word form information (lexeme). We measured BOLD responses in 14 native speakers of German in three different decision tasks, each focussing specifically on one level of lexical processing (conceptual, syntactic, and morpho-phonological). The test parameters were natural gender, grammatical gender, and word form derivation, respectively. Discrimination between words played backwards and complex sounds served as control task. Complex contrasts revealed a functional fractionation of the left inferior frontal gyrus for each level of lexical processing.     

Dismal: a spreadsheet for sequential data analysis and HCI experimentation

Dismal is a spreadsheet that works within GNU Emacs, a widely available programmable editor. Dismal has three features of particular interest to those who study behavior: (1) the ability to manipulate and align sequential data, (2) an open architecture that allows users to expand it to meet their particular needs, and (3) an instrumented and accessible interface for studies of human-computer interaction (HCI). Example uses of each of these capabilities are provided, including cognitive models that have had their sequential behavior aligned with subject’s protocols, extensions useful for teaching and doing HCI design, and studies in which keystroke logs from the timing package in Dismal have been used.     

Possible influence of linguistic musical background on perceptual pitch-matching tasks: a pilot study

Linguistic background has been identified as important in the perception of pitch, particularly between tonal versus nontonal languages. In addition, a link between native language and the perception of musical pitch has also been established. This pilot study examined the perception of pitch between listeners from tonal and nontonal linguistic cultures where two different styles of music originate. Listeners were 10 individuals born in China who ranged in age from 25 to 37 years and had spent on the average 30 mo. in the USA and 10 individuals, born on the Indian subcontinent, who ranged in age from 22 to 31 years, and had spent an average of 13 mo. in the USA. Listeners from both groups participated in two conditions. One condition involved listening to a selection of music characteristic of the individual's culture (China, pentatonic scale; Indian subcontinent, microtones), and one condition involved no music. All listeners within each condition participated in two voice pitch-matching tasks. One task involved matching the lowest and highest pitch of tape-recorded voices to a note on an electronic keyboard. Another task involved matching the voice pitch of tape-recorded orally read words to a note on the keyboard. There were no differences between the two linguistic groups. Methodological limitations preclude generalization but provide the basis for further research.     

A prototype analysis of forgiveness

Many definitions of forgiveness currently exist in the literature. The current research adds to this discussion by utilizing a prototype approach to examine lay conceptions of forgiveness. A prototype approach involves categorizing objects or events in terms of their similarity to a good example, whereas a classical approach requires that there are essential elements that must be present. In Study 1, participants listed the features of forgiveness. Study 2 obtained centrality ratings for these features. In Studies 3 and 4, central features were found to be more salient in memory than peripheral features. Study 5 showed that feature centrality influenced participants' ratings of victims involved in hypothetical transgressions. Thus, the two criteria for demonstrating prototype structure (that participants find it meaningful to judge features in terms of their centrality and that centrality affects cognition) were met.