Generalization in perceptual learning for speech

Lexical context strongly influences listeners’ identification of ambiguous sounds. For example, a sound midway between /f/ and /s/ is reported as /f/ in “sheri_’” but as /s/ in “Pari_.” Norris, McQueen, and Cutler (2003) have demonstrated that after hearing such lexically determined phonemes, listeners expand their phonemic categories to include more ambiguous tokens than before. We tested whether listeners adjust their phonemic categories for a specific speaker: Do listeners learn a particular speaker’s “accent”? Similarly, we examined whether perceptual learning is specific to the particular ambiguous phonemes that listeners hear, or whether the adjustments generalize to related sounds. Participants heard ambiguous /d/ or /t/ phonemes during a lexical decision task. They then categorized sounds on /d/-/t/ and /b/-/p/ continua, either in the same voice that they had heard for lexical decision, or in a different voice. Perceptual learning generalized across both speaker and test continua: Changes in perceptual representations are robust and broadly tuned.     

Perceptual learning for speech: Is there a return to normal?

Recent work on perceptual learning shows that listeners' phonemic representations dynamically adjust to reflect the speech they hear (Norris, McQueen, & Cutler, 2003). We investigate how the perceptual system makes such adjustments, and what (if anything) causes the representations to return to their pre-perceptual learning settings. Listeners are exposed to a speaker whose pronunciation of a particular sound (either /s/ or /integral/) is ambiguous (e.g., halfway between /s/ and /integral/). After exposure, participants are tested for perceptual learning on two continua that range from /s/ to /integral/, one in the Same voice they heard during exposure, and one in a Different voice. To assess how representations revert to their prior settings, half of Experiment 1's participants were tested immediately after exposure; the other half performed a 25-min silent intervening task. The perceptual learning effect was actually larger after such a delay, indicating that simply allowing time to pass does not cause learning to fade. The remaining experiments investigate different ways that the system might unlearn a person's pronunciations: listeners hear the Same or a Different speaker for 25 min with either: no relevant (i.e., 'good') /s/ or /integral/ input (Experiment 2), one of the relevant inputs (Experiment 3), or both relevant inputs (Experiment 4). The results support a view of phonemic representations as dynamic and flexible, and suggest that they interact with both higher- (e.g., lexical) and lower-level (e.g., acoustic) information in important ways.     

A Theoretical Examination of Immigrant Status and Substance Use among Latino College Students

ABSTRACT

Drawing on survey data from a sample of Latino college students, we examine the generalizability of social learning theory, general strain theory, social bond theory, and self-control theory to a Latino population and consider how these four theories can elaborate on the relationship between immigrant status and substance use. We find that social learning and general strain provide the most robust explanations of substance use across four outcomes. Also, third-plus generation respondents generally reported more substance use than first-generation respondents. Our findings suggest that this latter trend is due mostly to varying effect sizes in social learning by immigrant status.     

Rumination and intentional forgetting of emotional material

The tendency to respond to negative life events and negative mood states with ruminative thinking has been linked to emotion dysregulation and to a heightened risk for the onset and maintenance of emotional disorders. To further investigate this maladaptive response style, the present study examined whether rumination is linked to individual differences in the ability to intentionally forget emotional material. In a directed forgetting task, participants were instructed to memorise a list of positive and negative words and were subsequently told to forget these words. Next, participants were told to memorise a new list and, finally, recall was tested for all to-be-forgotten and to-be-remembered words. Our results demonstrate a close relation between rumination and recall in the forget condition but not in the remember condition. Specifically, compared to participants who scored low on the Ruminative Responses Scale (RRS), participants who scored high exhibited reduced forgetting of positive and negative to-be-forgotten words. These results remained stable when depression scores were included as a covariate suggesting that irrespective of depressive symptoms, rumination and intentional forgetting of emotional material are closely related.     

Associations between miscellaneous symptoms and symptom dimensions in adults with obsessive-compulsive disorder

Abstract

Obsessive-compulsive disorder (OCD) is a debilitating psychiatric condition with a heterogeneous array of obsessions and compulsions. Although factor analytic studies have identified symptom dimensions comprising the clinical presentation of OCD, many frequently reported miscellaneous symptoms are not considered in factor analytic studies because they do not fit conceptually within a particular symptom category, despite being functionally related. In the present study, we examined the associations between miscellaneous symptoms and OCD symptom dimensions in a sample of 111 adults with OCD. Overall, most miscellaneous symptoms were associated with one or more symptom dimensions in previously identified four- (14 of the 22 symptoms) and five-factor models (12 of the 22 symptoms). In both models, Contamination/Cleaning was the only dimension not related to any miscellaneous symptom. The present results provide information about which miscellaneous symptoms may be related to particular symptom dimensions, which will assist in clinical evaluations and help planning behavioral psychotherapy (e.g., hierarchy development).     

A methodological note on evaluating performance in a sustained-attention-to-response task

We evaluated the influence of speed–accuracy trade-offs on performance in the sustained attention to response task (SART), a task often used to evaluate the effectiveness of techniques designed to improve sustained attention. In the present study, we experimentally manipulated response delay in a variation of the SART and found that commission errors, which are commonly used as an index of lapses in sustained attention, were a systematic function of manipulated differences in response delay. Delaying responses to roughly 800 ms after stimulus onset reduced commission errors substantially. We suggest the possibility that any technique that affects response speed will indirectly alter error rates independently of improvements in sustained attention. Investigators therefore need to carefully explore, report, and correct for changes in response speed that accompany improvements in performance or, alternatively, to employ tasks that control for response speed.     

Randomized,placebo-controlled trial of cognitive-behavioral therapy alone or combined with sertraline in the treatment of pediatric obsessive–compulsive disorder

Background

To examine the efficacy of sequential sertraline and cognitive-behavioral therapy (CBT) treatment relative to CBT with pill placebo over 18 weeks in children and adolescents with obsessive–compulsive disorder (OCD).

Methods

Forty-seven children and adolescents with OCD (Range = 7–17 years) were randomized to 18-weeks of treatment in one of three arms: 1) sertraline at standard dosing + CBT (RegSert + CBT); 2) sertraline titrated slowly but achieving at least 8 weeks on the maximally tolerated daily dose + CBT (SloSert + CBT); or 3) pill placebo + CBT (PBO + CBT). Assessments were conducted at screening, baseline, weeks 1–9, 13, and 17, and post-treatment. Raters and clinicians were blinded to sertraline (but not CBT) randomization status. Primary outcomes included the Children's Yale-Brown Obsessive–Compulsive Scale, and response and remission status. Secondary outcomes included the Child Obsessive Compulsive Impact Scale–Parent/Child, Children's Depression Rating Scale-Revised, Multidimensional Anxiety Scale for Children, and Clinical-Global Impressions-Severity.

Results

All groups exhibited large within-group effects across outcomes. There was no group by time interaction across all outcomes suggesting that group changes over time were comparable.

Conclusions

Among youth with OCD, there was no evidence that sequentially provided sertraline with CBT differed from those receiving placebo with CBT.

ClinicalTrials.gov Identifier

NCT00382291.     

Cognitive reserve as a moderator of responsiveness to an online problem-solving intervention for adolescents with complicated mild-to-severe traumatic brain injury

Children and adolescents with traumatic brain injury (TBI) often experience behavior difficulties that may arise from problem-solving deficits and impaired self-regulation. However, little is known about the relationship of neurocognitive ability to post-TBI behavioral recovery. To address this question, we examined whether verbal intelligence, as estimated by Vocabulary scores from the Wechsler Abbreviated Scale of Intelligence, predicted improvements in behavior and executive functioning following a problem-solving intervention for adolescents with TBI. One hundred and thirty-two adolescents with complicated mild-to-severe TBI were randomly assigned to a six-month Web-based problem-solving intervention (CAPS; n = 65) or to an Internet resource comparison (IRC; n = 67) group. Vocabulary moderated the association between treatment group and improvements in metacognitive abilities. Examination of the mean estimates indicated that for those with lower Vocabulary scores, pre-intervention Metacognition Index scores from the Behavior Rating Inventory of Executive Function (BRIEF) did not differ between the groups, but post-intervention scores were significantly lower (more improved) for those in the CAPS group. These findings suggest that low verbal intelligence was associated with greater improvements in executive functioning following the CAPS intervention and that verbal intelligence may have an important role in response to intervention for TBI. Understanding predictors of responsiveness to interventions allows clinicians to tailor treatments to individuals, thus improving efficacy.     

Changing fit and fat bias using an implicit retraining task

Objective: To change implicit and explicit bias so that active obese people are regarded as more fit and normal weight sedentary people as less fit.

Design: Study one created a questionnaire that measured perceptions of active obese persons and sedentary normal weight persons on fitness-related items. Study two used a modified visual probe task to retrain perceptions regarding active obese persons and sedentary normal weight persons.

Main outcome measures: Self-reported explicit bias was measured with a questionnaire and implicit bias was measured with response times collected during a visual probe task.

Results: The questionnaire reliably measured ‘fitness and fatness’ perceptions. In study two, pairing images of active obese persons with positive activity-related words resulted in active obese persons being explicitly rated more fit; pairing images of normal weight sedentary persons with negative words associated with sedentary lifestyles increased endorsement of normal weight people as unfit. There were no changes in implicit bias.

Conclusions: Bias regarding how body weight is thought of relative to fitness can be altered by pairing images of obese persons being active with words such as ‘health’ and ‘fit’. This is evidence that representations of persons of all body weight should be used when promoting physical activity.