Learning in reverse: eight-month-old infants track backward transitional probabilities.

Numerous recent studies suggest that human learners, including both infants and adults, readily track sequential statistics computed between adjacent elements. One such statistic, transitional probability, is typically calculated as the likelihood that one element predicts another. However, little is known about whether listeners are sensitive to the directionality of this computation.

Predicting echo thresholds from speech onset characteristics.

Echo threshold variability has previously been examined using stimuli that are carefully controlled and artificial (e.g., clicks and noise bursts), while studies using speech stimuli have only reported average thresholds.

Development of perceptual expertise in emotion recognition.

How do children's early social experiences influence their perception of emotion-specific information communicated by the face? To examine this question, we tested a group of abused children who had been exposed to extremely high levels of parental anger expression and physical threat. Children were presented with arrays of stimuli that depicted the unfolding of facial expressions, from neutrality to peak emotions. The abused children accurately recognized anger early in the formation of the facial expression, when few physiological cues were available.

Dog is a dog is a dog: infant rule learning is not specific to language.

Human infants possess powerful learning mechanisms used for the acquisition of language. To what extent are these mechanisms domain specific? One well-known infant language learning mechanism is the ability to detect and generalize rule-like similarity patterns, such as ABA or ABB [Marcus, G. F.

Infant-Directed Speech Facilitates Word Segmentation.

There are reasons to believe that infant-directed (ID) speech may make language acquisition easier for infants. However, the effects of ID speech on infants' learning remain poorly understood. The experiments reported here assess whether ID speech facilitates word segmentation from fluent speech.

When cues collide: use of stress and statistical cues to word boundaries by 7- to 9-month-old infants.

Prior research suggests that stress cues are particularly important for English-hearing infants' detection of word boundaries. It is unclear, though, how infants learn to attend to stress as a cue to word segmentation. This series of experiments was designed to explore infants' attention to conflicting cues at different ages.

Pattern induction by infant language learners.

How do infants learn the sound patterns of their native language? By the end of the 1st year, infants have acquired detailed aspects of the phonology and phonotactics of their input language. However, the structure of the learning mechanisms underlying this process is largely unknown. In this study, 9-month-old infants were given the opportunity to induce specific phonological patterns in 3 experiments in which syllable structure, consonant voicing position, and segmental position were manipulated.

Asymmetries in contrast polarity processing in young human infants.

Luminance increments and decrements of equal magnitude are processed asymmetrically in the adult visual system. At detection threshold, decrements are slightly easier to detect than increments. At suprathreshold contrast levels decrements appear to have more contrast than increments when both differ from the background by the same absolute amount.

Early experience is associated with the development of categorical representations for facial expressions of emotion.

A fundamental issue in human development concerns how the young infant's ability to recognize emotional signals is acquired through both biological programming and learning factors. This issue is extremely difficult to investigate because of the variety of sensory experiences to which humans are exposed immediately after birth. We examined the effects of emotional experience on emotion recognition by studying abused children, whose experiences violated cultural standards of care.

Words in a sea of sounds: the output of infant statistical learning.

One of the first problems confronting infant language learners is word segmentation: discovering the boundaries between words. Prior research suggests that 8-month-old infants can detect the statistical patterns that serve as a cue to word boundaries. However, the representational structure of the output of this learning process is unknown.

Loudness constancy with varying sound source distance.

At a listener's ears, sound source power and sound source distance are confounded in measures of acoustic intensity, a physical property long thought to be the primary determinate of loudness. Although the relationship between sound source loudness and power is well known when source distance is fixed, relatively little is known about source loudness under conditions of varying distance. Here we show a robust loudness constancy, similar in many ways to visual size constancy, that results under distance-varying conditions that produce inaccurate estimates of source distance.

Monaural sound localization revisited.

Research reported during the past few decades has revealed the importance for human sound localization of the so-called "monaural spectral cues." These cues are the result of the direction-dependent filtering of incoming sound waves accomplished by the pinnae. One point of view about how these cues are extracted places great emphasis on the spectrum of the received sound at each ear individually.