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.     

Shift and deviate: Saccades reveal that shifts of covert attention evoked by trained spatial stimuli are obligatory

The premotor theory of attention predicts that motor movements, including manual movements and eye movements, are preceded by an obligatory shift of attention to the location of the planned response. We investigated whether the shifts of attention evoked by trained spatial cues (e.g., Dodd & Wilson, 2009) are obligatory by using an extreme prediction of the premotor theory: If individuals are trained to associate a color cue with a manual movement to the left or right, the shift of attention evoked by the color cue should also influence eye movements in an unrelated task. Participants were trained to associate an irrelevant color cue with left/right space via a training session in which directional responses were made. Experiment 1 showed that, posttraining, vertical saccades deviated in the direction of the trained response, despite the fact that the color cue was irrelevant. Experiment 2 showed that latencies of horizontal saccades were shorter when an eye movement had to be made in the direction of the trained response. These results demonstrate that the shifts of attention evoked by trained stimuli are obligatory, in addition to providing support for the premotor theory and for a connection between the attentional, motor, and oculomotor systems.     

Indexicals and utterance production

We highlight various non-standard mechanisms of communication to both motivate our response to what is known as the ‘answering machine paradoxes’ and to shed light on recent variants of these cases. We claim that the most intuitive solution to these paradoxes requires one to distinguish between the agent (of a context), the tokening of a sentence and the agent’s chosen mechanism of communicating this tokening.     

Separating perceptual and decisional attention processes in the identification and categorization of integral-dimension stimuli

Four observers performed matching, identification, and categorization with stimuli that varied along the integral dimensions: brightness and saturation. General recognition theory (F. G. Ashby & J. T. Townsend, 1986) was applied to quantify the separate influences of perceptual and decisional processes within and across tasks, with a focus on separating perceptual from decisional attention processes. Good accounts of the identification data were obtained from perceptual matching representation. This perceptual representation provided a good account of the categorization data, except when decisional selective attention to 1 stimulus dimension was required. Decisional selective attention reduced the attended-dimension perceptual variance relative to the unattended-dimension perceptual variance, with a larger reduction resulting when brightness, as opposed to saturation was attended. Implications for color vision research are discussed.     

Household hunger,standard of living and satisfaction with life in Alice,South Africa

The objective of this study was to investigate the relationships between household hunger, standard of living and satisfaction with life in a rural South African setting. Respondents were 442 randomly selected community dwellers from Alice, in the Eastern Cape (Xhosa speaking = 89.32%, females = 67%; age range 40–49 years). Multiple regression analysis was utilised to predict satisfaction with life from household hunger and standard of living. Low levels of household hunger, and low to moderate living standards predicted satisfaction with life. Resource support interventions with vulnerable communities should focus on poverty alleviation measures aimed at improving subjective satisfaction levels.     

Selective punishment early and late in fixed-ratio schedules of food reinforcement

Pigeons key pecked for grain on a fixed-ratio 100 schedule; electric shocks occurred intermittently at the fifteenth or eighty-fifth response in the ratio. In Experiment I, shock was at the fifteenth response for two birds, and at the eighty-fifth response for two others, in every sixth, twelfth, or eighteenth ratio. Rate of responding decreased as frequency of shock increased, and the pattern of responding included an increased initial pause and low rates or pause-run sequences that extended further into the ratio when shock was at the fifteenth response than when it was at the eighty-fifth response. Shock early in the ratio engendered longer initial pauses than shock late in the ratio. In Experiment II, four birds responded on a two-component multiple schedule in which shock occurred at the fifteenth response of the third ratio in the presence of a white keylight and at the eighty-fifth response of the third ratio in the presence of a green keylight. The overall rates of responding decreased as shock intensity increased. All four birds responded differentially to the white and green keylights, but with a pattern that varied between birds. In general, punishment reduced the probability of responses that preceded it, regardless of the ordinal position of those responses. Both studies confirm that the probability of responding is reduced less by aversive stimuli produced late in a fixed-ratio than by aversive stimuli produced early in a fixed-ratio.     

Children's understanding of their own phonological forms

The ability of young children to understand their own and other children's deviant phonological forms was tested. Children were better at understanding an unfamiliar adult's speech than they were at understanding their own or other childrens' speech. Their understanding was found to be related to the degree to which the deviant speech resembled the adult phonological form. It was concluded that children do not store their own deviant phonological forms for recognition in the same way that they store adult forms.     

The use of decomposition in probability assessments of continuous variables

In this study, decomposition is used as a tool for the assessment of continuous probability distributions. The goal of using decomposition is to obtain better calibrated probability distributions by expressing a variable as a known function of several component variables. Three target quantities were used in the study. Each was assessed holistically and using two different decompositions. Thus, each subject provided three distributions for each of the three target quantities. The recomposed assessments were compared to holistic assessments. The distributions obtained using decomposition were found to be much better calibrated than those obtained holistically. Two methods of aggregating distributions from multiple subjects were also examined. One involves aggregating (averaging) distributions before recomposing while the second method involves recomposing and then averaging distributions for the target variable. The second method was found to be slightly better, although both showed better calibration than was found in the individual assessments.