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Warren W Tryon

Publications and source records attributed to Warren W Tryon.

12 recordsLinked to original sources
PubMed2006

Reducing hyperactivity with a feedback actigraph: initial findings.

Schulman and colleagues demonstrated that classroom activity level can be reduced in hyperactive boys using activity-level feedback and positive reinforcement. This article reports preliminary results using a device that combines modern beeper and actigraphy technology for the purpose of measuring, monitoring, and modifying motor excess in children with confirmed diagnoses of Attention Deficit Hyperactivity Disorder (ADHD). Nine boys ranging in age from 8 to 9 years with the ADHD Combined Type wore prototype BuzzBee feedback actigraphs during school periods and were reinforced for activity-level reductions in the context of a simple pre/post research design. The findings indicated that 7 of the 9 boys reduced their activity level from 20 to 47% of baseline levels while the activity levels of the two remaining boys increased from 2 to 7% of baseline levels. These changes were statistically significant and constitute a large effect.

Attention Deficit Disorder with Hyperactivity↗
PubMed2006

The impact of borderline personality disorder and anxiety on neuropsychological performance in major depression.

Previous studies of neuropsychological performance in borderline personality disorder (BPD) have exhibited mixed results. The high rate of co-occurring major depressive disorder (MDD) in BPD makes it difficult to specify whether neuropsychological deficits in BPD predominantly reflect co-occurring MDD or unique aspects of their psychopathology. To address this issue, 22 participants with borderline personality disorder and concurrent major depressive disorder (BPD-MDD) and 33 participants with MDD and no concurrent personality disorder were compared on a neuropsychological battery that assessed seven domains of performance: general intellectual functioning, motor skill, psychomotor speed, attention, memory, working memory, and executive function. Neuropsychological performance did not differ between BPD-MDD and MDD. However, BPD-MDD participants reported higher levels of anger, anxiety, and of overall emotional distress compared to MDD. When levels of anxiety were controlled, BPD-MDD participants exhibited superior general intellectual performance, psychomotor speed, and attention. Deficits found in previous BPD samples may reflect their susceptibility to co-occurring MDD. The impact of anxiety on neuropsychological performance in BPD, though, indicates a need for future experimental studies of the effects of mood on cognitive function to determine whether mood dysregulation, rather than core depressive symptoms, underlie cognition impairments in BPD.

Adult↗
PubMed2005

Bimodal response sensitivity and bias in a test of sustained attention contrasting patients with schizophrenia and bipolar disorder to normal comparison group.

This study examined response discrimination (d') and bias (likelihood ratio) differentials in a computer-generated test of auditory and visual attention functioning. Patients with bipolar disorder (n=42) and schizophrenia (n=47) were contrasted to a normal comparison group (n=89) in two conditions: (a) simple modal responsivity (auditory and visual stimuli) and (b) ipsimodal (auditory/auditory and visual/visual) and crossmodal (auditory/visual and visual/auditory) responding. The results of this study indicated that in the simple modal condition both subject groups showed differential modal preferences but in opposite directions. The schizophrenic group showed a significant visual over auditory preference, committing more auditory commission and omission errors than visual errors. The bipolar group displayed a distinct auditory over visual response preference, committing significantly higher number of visual omission errors. Response bias analysis indicates that both diagnostic groups adopted a more liberal response bias, whereas the comparison group assumed a more conservative approach. For all groups response sensitivity improved as response bias became more neutral. The modal switching results indicated that all three groups tended to commit more commission errors (false alarms) in the auditory crossmodal switching condition (visual/auditory) by comparison with the other switching conditions. Between group comparisons for this condition showed that the schizophrenic group committed significantly more commission errors than the other groups. No significant medication effects were detected.

Adult↗
PubMed2005

Possible mechanisms for why desensitization and exposure therapy work.

Rosen and Davison [Rosen, G.M. and Davison, G.C. (2003). Psychology should list empirically supported principles of change (ESPs) and not credential trademarked therapies or other treatment packages. Behavior Modification, 27, 300-312] recommended that empirically supported principles be listed instead of empirically supported treatments because the latter approach enables the creation of putatively new therapies by adding functionally inert components to already listed effective treatments. This article attempts to facilitate inquiry into empirically supported principles by reviewing possible mechanisms responsible for the effectiveness of systematic desensitization and exposure therapy. These interventions were selected because they were among the first empirically supported treatments for which some attempt was made at explanation. Reciprocal inhibition, counterconditioning, habituation, extinction, two-factor model, cognitive changes including expectation, self-efficacy, cognitive restructuring, and informal network-based emotional processing explanations are considered. Logical problems and/or available empirical evidence attenuate or undercut these explanations. A connectionist learning-memory mechanism supported by findings from behavioral and neuroscience research is provided. It demonstrates the utility of preferring empirically supported principles over treatments. Problems and limitations of connectionist explanations are presented. This explanation warrants further consideration and should stimulate discussion concerning empirically supported principles.

Cognition↗
PubMed2005

The reliability and validity of two ambulatory monitoring actigraphs.

Evidence for the reliability and validity of two models of Ambulatory Monitoring, Inc. actigraphs was obtained by testing four instruments of each kind 10 times each on a precision pendulum. Correlation and coefficient of variation methods were used to analyze the data. Reliability coefficients of .98 were obtained for both models. Coefficient of variation methods yielded reliability coefficients of 92% for the MotionLogger model and 97% for the BuzzBee model. Validity coefficients of.99 were obtained for both models. However, MotionLogger means were found to differ by up to 36% from one instrument to another, whereas BuzzBee means differed by 10% at most. Issues of standardization and measurement units were discussed.

Equipment Design↗
PubMed2004

Chronic fatigue syndrome impairs circadian rhythm of activity level.

Some of the symptoms of chronic fatigue syndrome (CFS) are the same as for disrupted circadian rhythm. Activity level is frequently used to study circadian rhythm. Continuous waist activity measurements taken every minute 24 h/day for from 5 to 7 days in 10 controls and from 2 to 7 days in 8 patients with CFS yielded two primary findings: (a) lower daytime activity and (b) less regular activity-rest cycles in persons with CFS than in controls.

Adult↗
PubMed2004

Issues of validity in actigraphic sleep assessment.

OBJECTIVES: The Standards of Practice Committee of the American Sleep Disorders Association has supported the use of actigraphy in the assessment of sleep disorders. Pollak et al disagree. The objective of this paper is to identify and critically evaluate several theoretic and methodologic issues that are central to these divergent views regarding the valid use of actigraphy for sleep assessment. DESIGN: Critical review, analysis, and comment. SETTING: N/A. PATIENTS/PARTICIPANTS: N/A. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: N/A. CONCLUSIONS: (1) Coefficients of the validity of actigraphy exceed those associated with common medical tests and the best psychological tests. (2) Reasons why actigraphy should be held to a substantially higher empirical standard than common medical tests and the best psychological tests have yet to be advanced. (3) Differences between actigraphy and polysomnography are not random and can be reduced. (3a) Sleep onset is a gradual rather than a discrete process. Actigraphy keys on an earlier phase of the sleep-onset process than does polysomnography, resulting in systematic rather than random differences. (3b) A sleep switch device can be used to substantially increase the accuracy of sleep-onset times. (3c) The residual unreliability of polysomnographic data explains a portion of the differences between actigraphy and polysomnography. Actigraphy cannot be expected to agree more completely with polysomnography than polysomnography does with itself. (4) Complete agreement between actigraphy and polysomnography has been presumed, but achieving such a limit is theoretically impossible. Some lower maximum agreement limit should be identified. (5) Conclusions that actigraphy is not an accurate sleep-wake indicator and that it is inappropriate to infer sleep from actigraphy data are not supported by the findings. Conclusions reached, including caveats, by the Standards of Practice Committee remain supported.

Electroencephalography↗
PubMed2004

Construct validation of actigraphic sleep measures in hospitalized depressed patients.

This study validated wrist actigraphic-measured sleep in depressed patients using construct validity by experimental intervention methods. The experimental participants were 18 patients hospitalized for major depression. Control participants were hospital staff. A 2-between (depressed patients vs. controls) x 2-within (pre- vs. post-) experimental design was used. Sleep was evaluated for 1 week, 7 nights, using wrist actigraphy on hospitalization and for a second week just prior to discharge. Clinical improvement was corroborated by statistically significant changes in the Beck Depression Inventory and the Inventory to Diagnose Depression. Sleep-onset latency, number of nighttime awakenings, minutes awake after sleep onset, and sleep efficiency all improved significantly as hypothesized. Minutes of sleep changed in the predicted direction but not significantly. Significant differences from control participants remained at discharge regarding minutes awake after sleep onset and sleep efficiency. These findings extend practice guidelines for actigraphy established by the Standards of Practice Committee (1995) of the American Sleep Disorders Association.

Adult↗
PubMed2003

Validating internet research: a test of the psychometric equivalence of internet and in-person samples.

This study evaluated the psychometric equivalency of Web-based research. The Sexual Boredom Scale was presented via the World-Wide Web along with five additional scales used to validate it. A subset of 533 participants that matched a previously published sample (Watt & Ewing, 1996) on age, gender, and race was identified. An 8 x 8 correlation matrix from the matched Internet sample was compared via structural equation modeling with a similar 8 x 8 correlation matrix from the previously published study. The Internet and previously published samples were psychometrically equivalent. Coefficient alpha values calculated on the matched Internet sample yielded reliability coefficients almost identical to those for the previously published sample. Factors such as computer administration and uncontrollable administration settings did not appear to affect the results. Demographic data indicated an overrepresentation of males by about 6% and Caucasians by about 13% relative to the U.S. Census (2000). A total of 2,230 participants were obtained in about 8 months without remuneration. These results suggest that data collection on the Web is (1) reliable, (2) valid, (3) reasonably representative, (4) cost effective, and (5) efficient.

Adult↗