Audiovisual investigation of the loudness-effort effect for speech and nonspeech events.

There is some evidence that loudness judgments of speech are more closely related to the degree of vocal effort induced in speech production than to the speech signal's surface-acoustic properties such as intensity. Other researchers have claimed that speech loudness can be rationalized simply by considering the acoustic complexity of the signal. Because vocal effort can be specified optically as well as acoustically, a study to test the effort-loudness hypothesis was conducted that used conflicting audiovisual presentations of a speaker that produced consonant-vowel syllables with different efforts. It was predicted that if loudness judgments are constrained by effort perception rather than by simple acoustic parameters, then judgments ought to be affected by visual as well as auditory information. It is shown that loudness judgments are affected significantly by visual information even when subjects are instructed to base their judgments only on what they hear. A similar (though less pronounced) patterning of results is shown for a nonspeech "clapping" event, which attests to the generality of the loudness-effort effect previously thought to be special to speech. Results are discussed in terms of auditory, fuzzy logical, motor, and ecological theories of speech perception.     

Hypothalamic-pituitary-adrenal axis function and the metabolic syndrome X of obesity

Obesity has negative health consequences related to fat distribution, particularly the central or visceral accumulation of fat. The major complications associated with visceral obesity, termed the "Metabolic Syndrome of Obesity," or "Syndrome X," are type II diabetes, hypertension, and dyslipidemia. As with certain mood disorders, the syndrome may be a consequence of neuroendocrine perturbations typically associated with chronic stress. Our work with bonnet macaque monkeys provides an animal model for the relationship between early stress, behavioral and hypothalamic-pituitary-adrenal (HPA) axis dysregulation, and Syndrome X. During their infant's first half-year, mothers face a variable foraging demand (VFD), in which ample food varies unpredictably in the difficulty of its acquisition, and the offspring show persistent abnormalities in systems known to modulate stress and affective regulation. Early work on the bonnet macaque noted the emergence of a sample of spontaneously obese subjects as they matured. Using the VFD model, the current study showed that there was a clear relationship between early cerebrospinal fluid corticotropin-releasing factor levels and subsequently measured body mass index, supporting the hypotheses regarding the interactive roles of early experience and HPA axis dysregulation in the ontogeny of both metabolic and mood disorders.     

Stress, peer affiliation, and transforming growth factor-beta1 in differentially reared primates

A bidirectional regulatory interaction between the central nervous system and the immune system is largely provided by cytokines and their specific receptors, which are expressed by cells of both systems. Transforming growth factor-beta1 (TGF-beta1), produced by glial cells and lymphocytes and regulated by steroid hormones, is one such cytokine. In the current study, we examined the relationship between TGF-beta1 and peer affiliation in bonnet macaques (Macaca radiata) either reared normally or exposed as infants to conditions in which their mothers faced fluctuating requirements for food procurement (variable foraging demand [VFD]). Rearing under VFD conditions has been previously shown to produce dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis in these animals. Serum levels of TGF-beta1 after exposure to a moderate stressor had no correlation with peer affiliation under baseline conditions (r=.07), but were highly correlated with affiliation after subsequent challenge with a fear stimulus (r=.62). Affiliation after the fear stimulus also was inversely correlated with baseline levels of affiliation (r=-.71). These data suggest that changes in peripheral TGF-beta1 may be reflective of latent behavioral and biochemical propensities possibly related to affect. Further examination of the effects of early adversity will improve our understanding of the relationship between the HPA axis and immune function.     

Audiovisual Speech Web-Lab: An Internet teaching and research laboratory

Internet resources now enable laboratories to make full-length experiments available on line. A handful of existing web sites offer users the ability to participate in experiments and generate usable data. We have integrated this technology into a web site that also provides full discussion of the theoretical and methodological aspects of the experiments using text and simple interactive demonstrations. The content of the web site (http://www.psych.ucr.edu/avspeech/lab) concerns audiovisual speech perception and its relation to face perception. The site is designed to be useful for users of multiple interests and levels of expertise.     

Infant mental health home visiting therapists’ fidelity to the Michigan IMH-HV model in community practice settings

Implementation research suggests that fidelity to a therapeutic model is important for enhancing outcomes, yet can be difficult to achieve in community practice settings. Furthermore, few published studies have reported on characteristics of treatment fidelity. The present study examined fidelity to the Infant Mental Health Home Visiting (IMH-HV) model among 51 therapists with a range of experience practicing in community settings across the state of Michigan. IMH therapists completed fidelity checklists after every session with participating families to track use of 15 treatment strategies central to the IMH-HV model across the 12-month study period. Results indicated that the most commonly endorsed components utilized in home visits were developmental guidance and infant–parent psychotherapy, followed by the provision of emotional support. Use of IMH-HV components did not vary over time for the entire sample; however, patterns of strategies used showed somewhat more variability among more experienced therapists and when serving higher risk families. Findings demonstrate that IMH-HV therapists report a range of adherence to the model in community settings, with greatest fidelity to several model core components. Ongoing training in the flexible use of all core strategies may further enhance fidelity and contribute to positive outcomes for caregivers and their children receiving IMH-HV services.     

Infant mental health home visiting therapists’ reflective supervision self-efficacy in community practice settings

In recent years, there has been an increase in the research on reflective supervision, including the development of tools designed to measure reflective practice in the context of reflective supervision. The Reflective Supervision Self-Efficacy Scale for Supervisees (RSSESS) is a self-report measure that has been used in previous evaluations and is designed to assess perceived reflective practice self-efficacy for Infant Mental Health-Home Visiting (IMH-HV) therapists. Properties of the RSSESS including factor structure and reliability are explored in a first study that lays the foundation for the use of the RSSESS in an IMH-HV evaluation in the State of Michigan. IMH-HV therapists completed the RSSESS at 4 time points over a 12-month period and also completed a Clinician Profile Form that included questions about their IMH background and their work experience, including job satisfaction and burnout. Results indicated that the RSSESS is a reliable tool to measure change in reflective practice skills. IMH-HV therapists demonstrated growth in their use of reflective practice skills with families and their observational skills over the 12-month period. In addition, results indicated correlations between reflective supervision self-efficacy and job satisfaction as well as burnout.     

A computerized multidimensional measurement of mental workload via handwriting analysis

The goal of this study was to test the effect of mental workload on handwriting behavior and to identify characteristics of low versus high mental workload in handwriting. We hypothesized differences between handwriting under three different load conditions and tried to establish a profile that integrated these indicators. Fifty-six participants wrote three numerical progressions of varying difficulty on a digitizer attached to a computer so that we could evaluate their handwriting behavior. Differences were found in temporal, spatial, and angular velocity handwriting measures, but no significant differences were found for pressure measures. Using data reduction, we identified three clusters of handwriting, two of which differentiated well according to the three mental workload conditions. We concluded that handwriting behavior is affected by mental workload and that each measure provides distinct information, so that they present a comprehensive indicator of mental workload.     

Visual influences on interactive speech alignment

Speech alignment describes the unconscious tendency to produce speech that shares characteristics with perceived speech (eg Goldinger, 1998 Psychological Review 105 251-279). In the present study we evaluated whether seeing a talker enhances alignment over just hearing a talker. Pairs of participants performed an interactive search task which required them to repeatedly utter a series of keywords. Half of the pairs performed the task while hearing each other, while the other half could see and hear each other. Alignment was assessed by naive judges rating the similarity of interlocutors' keywords recorded before, during, and after the interactive task. Results showed that interlocutors aligned more when able to see one another suggesting that visual information enhances speech alignment.     

Discrimination tests of visually influenced syllables

In the McGurk effect, perception of audiovisually discrepant syllables can depend on auditory, visual, or a combination of audiovisual information. Undersome conditions, Vi8Ual information can override auditory information to the extent that identification judgments of a-visually influenced syllable can be as consistent as for an analogous audiovisually compatible syllable. This might indicate that visually influenced and analogous audiuvisually-compatible syllables-are-phictnetically equivalent. Experiments were designed to test this issue using a compelling visually influenced syllable in an AXB matching paradigm. Subjects were asked tomatch an audio syllable /val either to an audiovisually consistent syllable (audio /val-video /fa/) or an audiovisually discrepant syllable (audio /bs/-video ifa!). It was hypothesized that if the two audiovisual syllables were phonetically equivalent, then subjects should choose them equally often in the matching task. Results show, however, that subjects are more likely to match the audio /va/ to the audiovisually consistent /va/, suggesting differences in phonetic convincingness. Additional experiments further suggest that this preference is not based on a phonetically extraneous dimension or on noticeable relative audiovisual discrepancies.     

Rho-associated kinase in the gustatory cortex is involved in conditioned taste aversion memory formation but not in memory retrieval or relearning

Rho-associated kinase (ROCK) is intimately involved in cortical neuronal morphogenesis. The present study explores the roles of ROCK in conditioned taste aversion (CTA) memory formation in gustatory cortex (GC) in adult rat. Microinjection of the ROCK inhibitor Y-27632 into the GC 30 min before CTA training or 10 min after the conditioned stimulus (CS) impaired long-term CTA memory (LTM) formation. ROCK inhibitor had no effect on taste aversion when injected before the first LTM test day and did not alter taste aversion on subsequent test days. Microinjection of ROCK inhibitor into GC 30 min before preexposure to the taste CS had no effect on latent inhibition of CTA learning suggesting that ROCK is involved in CS-US association rather than taste learning per se. Cumulatively, these results show that ROCK is needed for normal CTA memory formation but not retrieval, relearning or incidental taste learning.