Modulation sensitivity in the perceptual organization of speech

In a spoken utterance, a talker expresses linguistic constituents in serial order. A listener resolves these linguistic properties in the rapidly fading auditory sample. Classic measures agree that auditory integration occurs at a fine temporal grain. In contrast, recent studies have proposed that sensory integration of speech occurs at a coarser grain, approximate to the syllable, on the basis of indirect and relatively insensitive perceptual measures. Evidence from cognitive neuroscience and behavioral primatology has also been adduced to support the claim of sensory integration at the pace of syllables. In the present investigation, we used direct performance measures of integration, applying an acoustic technique to isolate the contribution of short-term acoustic properties to the assay of modulation sensitivity. In corroborating the classic finding of a fine temporal grain of integration, these functional measures can inform theory and speculation in accounts of speech perception.     

The value tensions in Korean–American mother–child relationships while facilitating academic success

The current study explored mothers’ perspectives concerning their experiences in facilitating the academic success of their adolescents in American schools, using a naturalistic study design, data from transcribed personal interviews of 17 Korean–American mothers, and a phenomenological analysis approach (Giorgi, 1985, 1997). The purposes of this study were to (a) reveal the layers of context that influenced mothers’ thoughts, actions, and mother–child relationships as they assisted their adolescents in realizing academic success, a core value in Korean culture, and (b) uncover the relationship difficulties mothers perceived in these processes. The results indicated that mothers were influenced by their individualistic and collectivist cultural (meta) contexts as they tried to facilitate the academic success for their adolescents. Second, they were struggling with their competing Korean and American value systems (general context) in the adjustment processes of “becoming an American” and “remaining a Korean.” Third, mothers revealed their value tensions with adolescents (specific context) in school and family settings. In the family setting the tensions involved balancing obedience and respect with freedom and equality, similarity preference with diversity tolerance, and achievement and recognition with happiness and fulfillment.     

Automatic and Controlled Processes in the Analytisis of Hierarchical Structure

Targets are identified faster if they appear at the same level (global vs. local) as the target on the previous trial. This effect has been attributed to a controlled attentional process wherein participants attend to the level containing the target on trial n − 1, thus facilitating performance if target level repeats on trial n. An alternative explanation (Lamb & Yund, 1966) is that automatic activation of level-specific neural mechanisms is responsible. The controlled-process hypothesis predicts better performance whenever target level is predictable, because participants can anticipate, and thus attend to, the appropriate level. The automatic-process hypothesis predicts better performance when target level repeats, regardless of target-level predictability. In the present studies, level repetitions facilitated performance regardless of target-level predictability. The data support the automatic-process explanation of level repetition and other attentional effects. The data illustrate how an automatic process can give rise to performance that seems to reflect more cognitive or strategic mechanisms.     

Coding strategies,perceptual grouping,and the “variability effect” in free recall

Three experiments examined the effects of constant vs. varied input of letter strings on recall, and then examined the effects of such training in the learning of new lists of letter strings. Letter strings were constructed from pairs of trigrams spatially grouped, and were presented either consistently or with different spatial groupings on successive presentations. In Experiments I and II, varied input produced substantially greater recall than constant input. When transferred to a new list of letter strings, containing either the same general structure or a new scrambled structure, recall of the second list was determined primarily by conditions of first-list input, and unaffected by second-list structure. Although the "variability effect" did not appear in the training phase of Experiment III, Varied input led subjects to regroup or integrate the letter sequences more frequently and produced similar transfer effects as in Experiments I and II.     

On-line brain stimulation: Measurement of threshold of reinforcement

This program and interface for a small computer (PDP8/e) performs the following operations: generates and delivers constant current stimulation to the brain of an animal, monitors electrical resistance at the stimulating electrode, and calculates the threshold of reinforcement based upon the frequency of characteristic pauses in the animal’s responding.