The shift in infant preferences for vowel duration and pitch contour between 6 and 10 months of age

This study investigates the influence of the acoustic properties of vowels on 6‐ and 10‐month‐old infants’ speech preferences. The shape of the contour (bell or monotonic) and the duration (normal or stretched) of vowels were manipulated in words containing the vowels /i/ and /u/, and presented to infants using a two‐choice preference procedure. Experiment 1 examined contour shape: infants heard either normal‐duration bell‐shaped and monotonic contours, or the same two contours with stretched duration. The results show that 6‐month‐olds preferred bell to monotonic contours, whereas 10‐month‐olds preferred monotonic to bell contours. In Experiment 2, infants heard either normal‐duration and stretched bell contours, or normal‐duration and stretched monotonic contours. As in Experiment 1, infants showed age‐specific preferences, with 6‐month‐olds preferring stretched vowels, and 10‐month‐olds preferring normal‐duration vowels. Infants’ attention to the acoustic qualities of vowels, and to speech in general, undergoes a dramatic transformation in the final months of the first year, a transformation that aligns with the emergence of other developmental milestones in speech perception.     

The effect of attractiveness on food sharing preferences in human mating markets

The current study explored how physical attractiveness affects food sharing by studying payment preferences for hypothetical romantic dinner dates (a hypothetical mating market). We analyzed payment preferences, self-rated attractiveness, and rated attractiveness for hypothetical dates in 416 participants. We hypothesized that (1) men would be more likely to prefer to pay than would women, (2) attractive individuals of both sexes would be less willing to pay, and (3) preferences to enter an exchange would be influenced by the attractiveness of prospective partners such that (3a) men would prefer to pay for attractive women, and (3b) women would prefer to be paid for by attractive men. All hypotheses were supported by our results. Individuals with higher self-rated attractiveness were more likely to prefer that their date would pay for the meal, and we found clear sex differences in how the attractiveness of potential dates affected payment preferences. Male participants preferred to pay for dates that had higher facial attractiveness, while female participants preferred that attractive men would pay. Individuals show condition dependent financial preferences consistent with the provisioning hypothesis in this mating market that are adaptive to evaluations of their own quality and that of prospective partners.     

The contribution of postural bias to lateral preferences for holding human infants

When asked to hold an infant, 60-85% of adults hold on their left, so that the infant's head is to the left of their midline (Brüser, 1981; de Chateau, 1983; Saling & Tyson, 1981). The same group bias has been found even when persons are merely asked to imagine holding an infant (Nakamichi & Takeda, 1995; Harris, Almerigi, & Kirsch, 2000). A number of variables have been found to contribute modestly to the bias, including the sex and handedness of the holder. In the current study, the role of a new variable is investigated, namely, the feeling of comfort for holding an infant on a particular side as indexed by one's foot preference for acts of stabilizing or postural support. To test this hypothesis, 282 right-handed college students (218 women, 64 men) were given the imagine-hold task along with 4 questions about their foot preference for posture and balance. The results showed that, at least for women, the two measures were modestly but significantly related.     

Discrimination of color and pattern novelty in one-month human infants

Visual discrimination of novel colors and patterns by one-month infants was studied in two experiments where visual reinforcers were presented contingent upon infants' rate of nonnutritive, high-amplitude sucking. Discrimination was measured by recovery of sucking to the presentation of novel visual reinforcing stimuli following decrements in sucking to familiar visual stimuli. In Expt 1, following decrement to familiar stimuli, independent groups received either a change in color, pattern, both color and pattern, or no stimulus change. Reliable recovery was demonstrated for the three stimulus novelty groups relative to the no-change control. Experiment 2, employing achromatic visual reinforcers also showed reliable recovery to pattern change relative to no-change controls. These findings with one-month infants indicate discrimination between familiar and novel visual reinforcers on the basis of color and pattern differences and an increase due to novelty in the reinforcing effectiveness of visual stimuli. Individual subject differences in response decrement magnitude during familiarization were positively correlated with amount of response recovery to novelty.     

The effect of odors on human newborn infants under stress

Five-day-old human infants' responses to heelstick stress were assessed with behavioral and physiological indices. The subjects were divided randomly into three groups: the LAV group, who were presented with artificial odor of lavender during the heelstick; the MILK group, who were presented with artificial odor of milk during the heelstick; and the CONT group, who were presented with no special odors. The CONT group showed more adrenocortisol release in saliva than the other groups, but there were no differences between the two odors.     

Information,run structure and binary pattern complexity

Two information processing models of the perception of binary patterns are outlined. The H (k-span) model assumes S er;aluates the transitional uncertainty associated with the different k-tuples constituting the pattern. The H (run-span) model assumes S codes the pattern into runs and then evaluates the transitional uncertainty associated with the pattern’s run-tuples. Both models give a measure of the complexity of a pattern. The models are tested by using the complexity measures to predict various response indices of pattern complexity; e.g. judged pattern complexity, mean number of words to describe a pattern, accuracy of recall of a pattern. H (run-span) proved to be highly correlated with all of the pattern complexity indices. H (k-span) received only moderate support.     

社会偏好中的框架效应

社会偏好中的框架效应是指, 个体在决策中受到选择方案框架形式的影响而表现出合作、互惠及利他行为及倾向改变的现象, 是框架效应在社会偏好领域的运用。预期理论、错误知觉说、心理动力模型、情绪维护理论以及解释水平理论分别从价值函数、知觉偏差、内部心理动力、情绪及认知表征角度解释了社会偏好中的框架效应, 心理距离、价值取向、人格特质和文化等因素对社会偏好中的框架效应具有重要影响。未来的研究需要从社会偏好中的框架效应的心理机制与神经机制、研究范式及外部效度改进等方面作进一步探讨。     

The effect of contour closure on shape recognition

Recent research on the Gestalt principle of closure has focused on how the presence of closure affects the ability to detect contours hidden in cluttered visual arrays. Some of the earliest research on closure, however, dealt with encoding and recognizing closed and open shapes, rather than detection. This research re-addresses the relation between closure and shape memory, focusing on how contour closure affects the ability to learn to recognize novel contour shapes. Of particular interest is whether closed contour shapes are easier to learn to recognize and, if so, whether this benefit is due to better encoding of closed contour shapes or easier comparison of closed contour shapes to already learned shapes. The results show that closed contours are indeed easier to recognize and, further, that this advantage appears to be related to better encoding.     

The influence of novelty and complexity on exploratory behavior in 12-month-old infants

This study investigated the influence of the novelty of the environment and the novelty and complexity of the objects (toys) it contained on the exploratory behavior of 12-month-old infants. Each infant was given a choice between novel and familiar toys located in two adjacent rooms (toy rooms). The novelty of the objects was manipulated by allowing the infants to play with one set of toys during a 5-min familiarization trial prior to the choice trial. The novetly of the environment was manipulated by allowing some infants to see, enter, and remain in the toy rooms during the familiarization trial. Finally, the complexity of the objects was manipulated by varying the number of familiar and novel toys; some Ss had four toys in each set (complex array) and some had only one (simple array). The results indicate that all three factors influenced the infants' exploratory behavior. Ss first approached, and spent more time manipulating, the novel than the familiar toys; they spent more time in the toy rooms if they were novel; and they spent more time manipulating the complex array of toys than the simple array.     

Development of the 24-h rest-activity pattern in human infants

The development of the 24-h rest-activity pattern was investigated in human infants under naturalistic conditions as assessed by continuous actigraphy. Seven infants and their mothers were recorded for 4 (n=1), 6 (n=5) and 12 months (n=1) after birth. Periodogram analysis of rest-activity data was performed over consecutive 10-day intervals. A weak 24-h rest-activity pattern was already present in some infants during the newborn period. The magnitude of the 24-h component in individual periodograms increased across the first months following a saturating function. The time constants of fitted saturating exponential functions--reflecting the rate of development of the 24-h pattern--ranged from 49 to 110 days (n=6) indicating a large interindividual variability. Furthermore, intraindividual variation was observed; the magnitude of the 24-h rest-activity component showed fluctuations around the trend. Miniaturized actigraphs are ideal tools for long-term longitudinal monitoring of rest-activity behavior in infants.     

The leader effect and behavioral complexity

This paper reviews research into the impact that leaders have on performance outcomes and into the identification of behavioral competencies associated with superior leadership effectiveness. The review indicates that around twenty percent of performance outcomes may be attributed to leaders depending on the level of discretion they exercise. Eleven High-Performance Competencies (H-PC) are identified that appear associated with the leader effect; several of these H-PC derive from Behavioral Complexity Theory as developed and explored by Professor Siegfried Streufert and his colleagues.