Biomedical subjects

Dawn M Marsh

Publications and source records attributed to Dawn M Marsh.

10 recordsLinked to original sources

PubMed2005

Laboratory behavioral measures of impulsivity.

Previous research and theory have conceptualized impulsivity as a multifaceted construct that requires multiple modes of measurement for accurate assessment. This article describes a software package that includes four paradigms for measuring multiple and unique aspects of impulsivity. Specifically, four tasks are described: (1) the two choice impulsivity paradigm, (2) the single key impulsivity paradigm, (3) the GoStop impulsivity paradigm, and (4) the time paradigm. These tasks measure processes related to the capacity to tolerate delay for reward, to inhibit an already initiated response, and to estimate the passage of time. These processes have been found to be important to the understanding of impulsive behaviors. The programs are flexible and allow the experimenter to manipulate a number of parameters related to delay-reward contingencies, timing, performance feedback/payment, and data output variables. Manipulation of these parameters makes the paradigms scalable to a wide range of ability levels and appropriate for samples ranging from children to adults. The four paradigms in this software package are available at no cost and can be obtained by contacting the corresponding author.

Animals↗

PubMed2004

Suicidal behaviors and drug abuse: impulsivity and its assessment.

Impulsivity appears to play an important role in suicidal behaviors and drug abuse, which are two psychiatric problems that may interact with one another. Interpretation of the literature on impulsivity in these behaviors may be complicated by the variety of measurement techniques for the assessment of impulsivity. There are three general types of impulsivity assessment: self-report, biological, and laboratory behavioral. Because laboratory behavioral measures both meet an operational definition of impulsivity and are sensitive to state-dependent changes in impulsivity, this paper presents data that focuses on laboratory behavioral performance among samples emitting suicidal behaviors or substance abuse. To better account for influence of impulsivity in these psychiatric disturbances, no single source of measurement should be used without the consideration of other types of instruments.

Decision Making↗

PubMed2004

Age at first drink relates to behavioral measures of impulsivity: the immediate and delayed memory tasks.

BACKGROUND: This study examined the relationship between laboratory-measured impulsivity and age at first drink. METHODS: Using a laboratory behavioral measure of impulsivity [Immediate (IMT) and Delayed Memory Tasks (DMT)], we compared two groups of women differing in their self-reported age at first drink (early-onset drinking, age <18 years, n = 40; late-onset drinking, age > or =21 years, n = 23). It was expected that those who first consumed alcohol before the legal drinking age (i.e., early onset) would perform in a more impulsive manner on the laboratory behavioral measure than the late-onset drinkers. RESULTS: The main finding was that the early-onset group (IMT: mean, 28.7%; DMT: mean, 30.4%) had increased commission error rates compared with the late-onset group (IMT: mean, 21.2%; DMT: mean, 15.5%) during both the IMT [ANOVA:F (1,61) = 4.30; p = 0.042; f = 0.27] and DMT [F (1,61) = 10.76; p = 0.002; f = 0.42]. Age at first drink was significantly correlated with DMT commission errors (r = -0.23; p = 0.037), although this was only at the trend level for IMT commission errors (r = -0.20; p = 0.062); these correlations are likely to be underestimates because of range restriction of the age variable. CONCLUSIONS: These results demonstrate that differences in impulsive behavioral responding are distinguishable even between groups of alcohol drinkers who are not experiencing clinically significant problems with alcohol.

Adult↗

PubMed2004

Laboratory measured behavioral impulsivity relates to suicide attempt history.

The purpose of this study was to examine the relationship between laboratory behavioral measured impulsivity (using the Immediate and Delayed Memory Tasks) and suicidal attempt histories. Three groups of adults were recruited, those with either: no previous suicide attempts (Control, n = 20), only a single suicide attempt (Single, n = 20), or multiple suicidal attempts (Multiple, n = 10). As hypothesized, impulsive responses increased with the number of suicide attempts (Control < Single < Multiple). This study helps to demonstrate how laboratory behavioral measures of impulsivity can be used to discriminate groups based on suicidal histories among samples not currently exhibiting significant suicidal behaviors.

Adult↗

PubMed2003

Familial transmission of Continuous Performance Test behavior: attentional and impulsive response characteristics.

Continuous Performance Tests (CPTs) provide information on attentional processing and impulsive behavior. The results of previous research that used self-report measures have provided evidence for familial transmission (through genetic and/or environmental influences) of impulsive characteristics. The authors of the present study examined whether the impulsive behavioral parameters that are measured by the CPT also share familial relationships. The researchers asked 26 healthy parent-adolescent pairs to complete the Immediate and Delayed Memory Tasks (IMT/DMT; D. M. Dougherty, 1999; D. M. Dougherty, D. M. Marsh, & C. W. Mathias, 2002), a modified CPT (B. A. Cornblatt, N. J. Risch, G. Faris, D. Friedman, & L. Erlenmeyer-Kimling, 1988; H. E. Rosvold, A. Mirsky, I. Sarason, E. D. Breansome, Jr., & L. H. Beck, 1956), and the Barratt Impulsiveness Scale (BIS; J. H. Patton, M. S. Stanford, & E. S. Barratt, 1995), a self-report measure. The main findings can be summarized as follows: (a) commission errors (but not correct detections) on the IMT and DMT were correlated between parents and their adolescent children, (b) adolescents emitted a higher proportion of commission errors than did their parents, and (c) self-reported impulsivity (i.e., BIS) was correlated with commission errors for parents, but not for adolescents. The findings of this study support the use of an objective behavioral measure of impulsivity to assess familial relationships of impulsivity.

Adolescent↗

PubMed2003

Behavioral impulsivity paradigms: a comparison in hospitalized adolescents with disruptive behavior disorders.

BACKGROUND: Behavioral impulsivity paradigms vary widely and studies using these measures have typically relied on a single measure used in isolation. As a result, comparisons between measures are difficult, with little consensus regarding which method may be most sensitive to individual impulsivity differences of different populations. METHOD: A single testing session of each of four different impulsivity tasks was completed by two groups of adolescents aged 13-17: hospitalized inpatients with disruptive behavior disorders (DBD; n = 22) and controls (n = 22). Tasks included two rapid-decision (IMT/DMT and GoStop) and two reward-directed (TC and SKIP) impulsivity paradigms. Behavioral testing took place within 3 days of hospitalization for the adolescents with DBD. RESULTS: Compared to controls, the DBD group exhibited higher commission error rates, lower inhibited response rates after a stop-signal, and twice as many reward-directed responses even after IQ differences between the groups were taken into account. When the four paradigms were compared, effect-size calculations indicated that the two rapid-decision paradigms were more sensitive to group differences than the reward-directed tasks. CONCLUSIONS: Despite the initiation of pharmacotherapy within the first 3 days of hospitalization, in contrast to the control group, the adolescents with DBD performed consistently with what has been operationally defined as impulsivity. Based on these results, these tasks appear to measure similar, but unique components of the impulsivity construct. With further study, laboratory behavioral paradigms may prove to be useful additions to current clinical diagnostic and treatment procedures in a variety of psychiatric populations.

Adolescent↗

PubMed2003

Commission error rates on a continuous performance test are related to deficits measured by the Benton Visual Retention Test.

This study is one in a series investigating the relationship between impulsive behavior on a Continuous Performance Test (i.e., the Immediate and Delayed Memory Task) and other cognitive deficits measured by clinical instruments. Forty-two adolescents were selected for two groups, controls and hospitalized patients with disruptive behavior disorders. Each adolescent completed the Immediate and Delayed Memory Task and the Benton Visual Retention Test. Our main findings were that, even when controlling for IQ, the Immediate and Delayed Memory Task commission errors were associated with adverse Benton performance, but only in the patient group. These results may be explained by a shared association between processes of impulsivity and other deficits of executive control that may interfere with successful performance of the Benton.

Adolescent↗

PubMed2002

Laboratory-measured aggressive behavior of women: acute tryptophan depletion and augmentation.

Plasma L-tryptophan (Trp) reductions have been related to aggression increases in men. Impairment of serotonin synthesis and neurotransmission is one explanation. Using repeated-measures, this Trp manipulation study measured laboratory-induced aggression in 12 women after Trp augmentation (T+), depletion (T-), and food-restricted (fasting control) conditions. Participants were provoked with periodic subtraction of money from their task earnings by a (fictitious) partner. Aggression was defined as the number of point subtractions participants made from their fictitious partner. Participants completed five testing sessions under each condition. T+ decreased aggressive responses and T- increased aggressive responses. Post-hoc analyses showed changes in aggressive behavior were specific to women with higher fasting control plasma Trp, which is consistent with research demonstrating that men with higher levels of baseline Trp are more aggressive. These findings indicate that both T+ and T- can influence aggressive behavior and that certain subgroups of women may be more susceptible to serotonin manipulation.

Adolescent↗

PubMed2002

Reliability estimates for the immediate and delayed memory tasks.

The Immediate and Delayed Memory Tasks are variations of the Continuous Performance Test. While previous research with the tasks has focused on group performance across multiple blocks and sessions, reliability estimates have not been established. We estimated reliability (1) between blocks of a single testing session (N=106), (2) across four sessions within a single testing day (N=20), and (3) across sessions on four consecutive testing days (N=20). Analyses indicated that the primary variable of interest, i.e., commission of errors, showed acceptable reliability within and across testing periods.

Adult↗

PubMed2002

Immediate and delayed memory tasks: a computerized behavioral measure of memory, attention, and impulsivity.

The Immediate and Delayed Memory Task (IMT/DMT), a variant of the Continuous Performance Test (CPT), is a new software package designed to be a flexible research tool for the study of attention, memory, and impulsivity. This package allows researchers to determine the design to be used during a testing session and to manipulate many of the parameters. It features two components: the IMT and the DMT, both of which present sequential 2- to 7-digit stimuli with variable presentation rates and intertrial intervals. Subjects respond to identically matched stimuli presented consecutively, spanning a brief period of time (IMT), or to stimuli spanning a greater period of time (during which intervening stimuli to be ignored appear; DMT). Task complexity can be adjusted to suit applications for both children and adults. Preliminary studies have demonstrated that these laboratory tasks are sensitive to group differences, produce stable baselines of performance, and are sensitive to drug-induced performance decrements.

Attention↗