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The Immediate and Delayed Memory Task (IMT/DMT) program is a modified Continuous Performance Test that produces levels of performance that are sensitive to both group differences and pharmacological manipulation, even in high functioning populations. The IMT/DMT is designed to measure response initiation in impulsive behavior. |
Immediate and Delayed Memory Tasks (IMT/DMT)
The IMT/DMT is a continuous performance test that was designed to assess impulsive behavior. The Immediate Memory Task involves comparison of consecutively presented number and responding in those instances when the current number matches the number immediately before it (called a correct detection). The Delayed Memory Task similarly involves responding to matching numbers, but the numbers to be compared a separated by a filler sequence (e.g. 12345). 
Like all continuous performance tests, the IMT/DMT involves selectively responding target stimuli and avoiding responses to non-target stimuli that are presented in rapid sequence. For many years, continuous performance tests were primarily analyzed in terms of success in identifying target stimuli, which have been interpreted as measuring sustained attention. The characteristics of these test were selected to maximize sensitivity to individual differences in target responding and typically rates of non-target responding were low.
The IMT/DMT was created to test the notion that the non-target responding could be a sensitive measure impulsivity. The parameters of this new continuous performance test were modified so that certain types of non-target responding could be interpreted within a definition of impulsive behavior. The innovation of the IMT/DMT is the inclusion of catch stimuli that are very similar to targets: they match on all but one digit with the target sequence. This is in contrast with other non-target stimuli that
are random and share very little overlap with the 
target. The concept here is that these very similar,
catch stimuli, require a long period of information processing in order to resolve as different from the target. More impulsive individuals will respond to these catch trials more often, because they emit the behavior prior to the completion of information processing. This is called by the authors Response Initiation Impulsivity. Another perspective has been to refer to this type of impulsivity as Rapid Response Impulsivity.
Inclusion of the catch trials and the timing of the stimulus delivery produce a response range that is broad and normally distributed. Additionally, the rates of impulsive responding) were sufficiently high that the test (1) avoids floor effects among higher functioning populations; and (2) is sensitive to detection of not just increases, but also decreases, in impulsive responding in response to an intervention.
*While these are the default task settings, many aspects of the IMT/DMT stimulus parameters are readily modifiable using the setup screen.
Immediate and Delayed Memory Tasks Setup Screen
Analyses of the Immediate and Delayed Memory Tasks
What variable is used to test impulsivity?
The impulsive responses on the IMT/DMT are commission errors: the responses to the catch stimuli. However, in many populations or treatment settings these commission errors must be interpreted within the context of the overall response rates and accuracy of performance. For this reason, it has often been more useful to report the impulsive response as the ratio of commission errors to correct detections. This formula is defined as:
(Number of commission errors / number of catch trials) / (Number of correct detections / number of target trials)
How is interpretability of performance assessed?
Performance based measures of impulsivity must be evaluated for the interpretability of their scores. While most scores will be interpretable, some data may be excluded when participant cooperation, effort, and/or comprehension is in question.
Evaluation of performance interpretability requires thoughtful examination of responses to the non-impulsive stimuli.
Questions must be asked about how low of correct detection rates and how high of filler error rates are acceptable. There is a range of correct detections reflecting low to high levels of sustained attention. However at some low level of correct responding to target stimuli, there arises uncertainty about the interpretability of performance. If correct detections are too low, it is likely because the participant either did not understand the response requirements of the test or was unable to exert effort to perform the task. In these situations, impulsive performance should not be interpreted. A similar concept applies to filler errors; response rates to the random non-matching should be low, and when they rise too high, again understanding or effort of the participant is called into question.
What are recommended cut-off’s for correct detection and filler error rates?
This really depends on your local population. Having examined large, international datasets with diverse populations, it is apparent that that exclusion criteria must be based on your local population. We encourage you to contact the test authors to develop an algorithm for selecting an inclusion criterion. Additionally, we recommend reporting these criteria as well as the correct detection and filler error rates in publications with the IMT/DMT.
Immediate and Delayed Memory Tasks Citation
When citing this instrument in a publication, please use the following reference:
Immediate and delayed memory tasks: a computerized behavioral measure of memory, attention, and impulsivity.
Dougherty DM, Marsh DM, Mathias CW (2002).
Behavioral Research Methods: Instruments and Computers, 34, 391-398.
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Immediate and Delayed Memory Tasks Bibliography
The effects of heroin administration and drug cues on impulsivity
Jones JD, Vadhan NP, Luba RR, Comer SD. (2016).
Journal of Clinical and Experimental Neuropsychology, 38, 709-720. 
Do individuals higher in impulsivity drink more impulsively? A pilot study within a high risk sample of young adults.
Stevens AK, Littlefield AK, Talley AE, Brown JL. (2016).
Addictive Behavior, 65, 147-153.
Factors associated with money mismanagement among adults with severe mental illness and substance abuse
Moore, BA, Black AC, Rosen MI. (2016).
International Journal of Mental Health and Addiction, 14, 400-409.
Machine-learning identifies substance-specific behavioral markers for opiate and stimulant dependence.
Ahn, W.Y., and Vassileva, J. (2016).
Drug and Alcohol Dependence, 161, 247-257.
Utility of machine-learning approaches to identify behavioral markers for Substance Use Disorders: Impulsivity dimensions as predictors of current Cocaine Dependence
Ahn, W. Y., Ramesh, D., Moeller, F. G., and Vassileva, J. (2016).
Frontiers in Psychiatry, http://dx.doi.org/10.3389/fpsyt.2016.00034
The effects of oral d-amphetamine on impulsivity in smoked and intranasal cocaine users.
Reed, S. C., Evans, S. M. (2016).
Drug and Alcohol Dependence, 163, 141-152.
Neurocognitive and psychiatric dimensions of hot, but not cool, impulsivity predict HIV sexual risk behaviors among drug users in protracted abstinence.
Wilson, M. J., and Vassileva, J. (2016).
American Journal of Drug and Alcohol Abuse, 42, 231-241.
Effects of tryptophan depletion and a simulated alcohol binge on impulsivity
Dougherty, D. M., Mullen, J., Hill-Kapturczak, N., Liang, Y., Karns, T. E., Lake, S. L., Mathias, C. M., and Roache, J. D. (2015).
Experimental and Clinical Psychopharmacology, 23, 109-121.
Further evidence of the heteroogeneous nature of impulsivity.
Caswell AJ, Bond R, Duka T, Morgan MJ (2015).
Pesonality and Individual Differences, 76, 68-74.
Trait impulsivity and increased pre-attentional sensitivity to intense stimuli in bipolar disorder and controls
Lijffijt M, Lane SD, Moeller FG, Steinberg JL, Swann AC. (2015).
Journal of Psychiatric Research, 60, 73-80.
Gender moderates the relationship between impulsivity and sexual risk-taking in a cocaine-using psychiatric outpatient population
Black AC, McMahon TJ, Potenza MN, Fiellin LE, Rosen MI. (2015).
Personality and Individual Differences, 75, 190-194.
Verbal versus physical aggression in Intermittent Explosive Disorder.
Look AE, McCloskey MS, Coccaro EF. (2015).
Psychiatry Research, 225, 531-539.
Attentional capacities of children with autism spectrum disorder
Shahrokhi H, Mahmood Aliloo M, Mehdizadeh Fanid L, Amiri S, Yadegari N. (2015).
Neuropsychiatrie de l Enfance et de l Adolescence, 60, S208
Sex differences in cognitive and motor impulsivity among users of different classes of drugs in protracted abstinence
Wilson MJ, VAsilev G, Moeller FG, Vassileva J (2015).
Drug and Alcohol Dependence, 146, e24.
Allopregnanolone association with psychophysiological and cognitive functions during acute smoking abstinence in premenopausal women.
Allen AM, al'Absi M, Lando H, Allen SS (2015)
Experimental and Clinical Psychopharmacology, 23, 22-28.
Executive functioning and suicidal behavior among veterans with and without a history of traumatic brain injury.
Brenner LA, Bahraini N, Homaifar BY, Monteith LL, Nagamoto H, Dorsey-Holliman B, Forster JE. (2015).
Archives of Physical Medicine and Rehabilitation, 96, 1411-1418.
Alcohol intoxication alters cognitive skills mediated by frontal and temporal brain regions
Magrys SA, Olmstead MC (2014).
Brain and Cognition, 85, 271-276.
Heroin and amphetamine users display opposite relationships between trait and neurobehavioral dimensions of impulsivity
Vassileva J, Paxton J, Moeller FG, Wilson MJ, Bozgunov K, Martin EM, Gonzalez R, Vasilev G. (2014).
Addictive Behavior, 39, 652-629.
Toward a theory of distinct types of "impulsive" behaviors: A meta-analysis of self-report and behavioral measures
Sharma L, Markon KE, Clark LA (2014).
Psychological Bulletin, 140, 374-408.
An investigation of the effects of antiretroviral central nervous system penetration effectiveness on procedural learning in HIV+ drug users
Wilson MJ, Martin-Engel L, Vassileva J, Gonzalez R, Martin EM (2013).
Journal of Clinical and Experimental Neuropsychology, 35, 915-925.
Pre-attentive information processing and impulsivity in bipolar disorder.
Swann AC, Lijffijt M, Lane SD, Steinberg JL, Acas MD, Cox B, Moeller FG. (2013).
Journal of Psychiatry Research, 47, 1917-1924.
Relations among behavioral and questionnaire measures of impulsivity in a sample of suicide attempters
Bagge CL, Littlefield AK, Rosellini AJ, Coffey SF (2013)
Suicide and Life-Threatening Behavior, 43, 460-467.
Norepinephrine and impulsivity: effects of acute yohimbine
Swann AC, Lijffijt M, Lane SD, Cox B, Steinberg JL, Moeller FG. (2013).
Psychopharmcology, 229, 83-94.
Effects of escitalopram on attentional bias to cocaine-related stimuli and inhibitory control in cocaine-dependent subjects
Liu S, Lane SD, Schmitz JM, Cunningham KA, John VP, Moeller FG. (2013).
Journal of Psychopharmacology, 27, 801-807.
Effects of short-term varenicline administration on emotional and cognitive processing in healthy, non-smoking adults: a randomized, double-blind, study
Mocking RJ, Patrick Pflanz C, Pringle A, Parsons E, McTavish SF, Cowen PJ, Harmer CJ. (2013).
Neuropsychopharmacology, 38, 476-484.
Impulsivity in relation to stress in patients with Borderline Personality Disorder with and without co-occurring Attention-Deficit/Hyperactivity Disorder
Krause-Utz A, Sobanski E, Alm B, Valerius G, Kleindienst N, Bohus M, Schmahl C. (2013).
The Journal of Nervous and Mental Disease, 201, 116-123
Volunteerism and self-selection bias in human positron emission tomography neuroimaging research
Oswald LM, Wand GS, Zhu S, Selby V (2013).
Brain Imaging and Behavior, 7, 163-176.
Profile of male adolescents with conduct disorder on intellectual efficacy, cognitive flexibility, cognitive coping, impulsivity and alexithymia: A comparison with high-risk controls
Pihet, S; Suter, M; Halfon, O; Stephan, P. (2012).
European Journal of Psychiatry, 26, 215-226.
Alcohol increases impulsivity and abuse liability in heavy drinking women
Reed SC, Levin FR, Evans SM. (2012)
Experimental and Clinical Psychopharmacology, 20, 454-465.
The relationship between impulsive choice and impulsive action: a cross-species translational study
Broos N, Schmaal L, Wiskerke J, Kostelijk L, Lam T, Stoop N, Weierink L, Ham J, de Geus EJ, Schoffelmeer AN, van den Brink W, Veltman DJ, de Vries TJ, Pattij T, Goudriaan AE (2012)
PLoS One, 75, e36781. 
Working memory load modulation of parieto-frontal connections: Evidence from dynamic causal modeling
Ma LS, Steinberg JL, Hasan KM, Narayana PA, Kramer LA, Moeller FG (2012).
Human Brain Mapping, 33, 1850-1867.
Traumatic brain injury, executive functioning, and suicidal behavior: A brief report
Homaifar BY, Brenner LA, Forster JE, Nagamoto H. (2012).
Rehabilitation Psychology, 57, 337-341.
Neurocognitive performance in drug-dependent males and females with posttraumatic stress disorder symptoms
Paxton, JL; Vassileva, J; Gonzalez, R; Maki, PM; Martin, EM (2012).
Journal of Clinical and Experimental Neuropsychology, 34, 521-530.
Nonsuicidal self-injury: Relationship to behavioral and self-rating measures of impulsivity and aggression
McCloskey MS, Look AE, Chen EY, Pajoumand G, and Berman ME (2012).
Suicide and Life-Threatening Behavior, 42, 197-209.
The relationship between self-report and lab task conceptualizations of impulsivity
Cyders MA, and Coskunpinar A (2012).
Journal of Research in Personality, 46, 121-124.
Different measures of impulsivity in patients with anxiety disorders: A case control study
Del Carlo A, Benvenuti M, Fornaro M, Toni C, Rizzato S, Swann AC, Dell'Osso L, and Perugi G (2012).
Psychiatry Research, 197, 231-236.
Adults with a family history of alcohol related problems are more impulsive on measures of response initiation and response inhibition.
Acheson, A., Richard, D. M., Mathias, C. W., and Dougherty, D. M. (2011).
Drug and Alcohol Dependence, 117, 198-203.
Criminal conviction, impulsivity, and course of illness in bipolar disorder
Swann AC, Lijffijt M, Lane SD, Kjome KL, Steinberg JL, and Moeller FG (2011).
Bipolar Disorders, 13, 173-181.
Interacting mechanisms of impulsivity in bipolar disorder and antisocial personality disorder
Swann AC, Lijffijt M, Lane SD, Steinberg JL, and Moeller FG (2011)
Journal of Psychiatry Research, 45, 1477-1482.
Do executive and reactive disinhibition mediate the effects of familial substance use disorders on adolescent externalizing outcomes?
Handley ED, Chassin L, Haller MM, Bountress KE, Dandreaux D, Beltran I (2011).
Journal of Abnormal Psychology, 12, 528-542.
Impulsivity in Anxiety Disorder Patients: Is it related to comorbid cyclothymia?
Perugi G, Del Carlo A, Benvenuti M, Fornaro M, Toni C, Akiskal K, Dell'Osso L, Akiskal H (2011).
Journal of Affective Disorders, 133, 600-606.
Effects of acute tryptophan depletion on three types of behavioral impulsivity
Dougherty DM, Richard DM, James LM, and Mathias CW (2010).
International Journal of Tryptophan Research, 3, 99-111.
The effects of progesterone pretreatment on the response to oral d-amphetamine in women
Reed, SC, Levin FR, and Evans SM (2010).
Hormones and Behavior, 58, 533-543.
Relationship between impulsivity and decision making in cocaine dependence.
Kjome KL, Lane SD, Schmitz JM, Green C, Ma L, Prasla I, Swann AC, and Moeller FG (2010).
Psychiatry Research, 178, 299-304.
Working memory fMRI activation in cocaine-dependent subjects: Association with treatment response.
Moeller FG, Steinberg JL, Schmitz JM, Ma L, Liu S, Kjome KL, Rathnayaka N, Kramer LA, and Narayana PA (2010).
Psychiatry Research: Neuroimaging, 181, 174-182.
The short (S) allele of the serotonin transporter polymorphism and acute tryptophan depletion both increase impulsivity in men.
Walderhaug E, Herman AI< Magnusson A, Morgan MJ, and Landro NI (2010).
Neuroscience letters, 473, 208-211.
Distinctions in behavioral impulsivity: Implications for substance abuse research.
Dougherty DM, Mathias CW,Marsh-Richard DM, Furr RM, Nouvion SO, Dawes MA (2009).
Addictive Disorders and Their Treatment, 8, 61-73.
Fifty years of the Barratt Impulsiveness Scale: An update and review.
Stanford MS, Mathias CW, Dougherty DM, Lake SL, Anderson NE, Patton JH (2009).
Personality and Individual Differences, 47, 385-395.
Trait impulsivity and response inhibition in antisocial personality disorder.
Swann AC, Lijffijt M, Lane SD, Steinberg JL, Moeller FG (2009).
Journal of Psychiatric Research, 43, 1057-1063.
P50, N100, and P200 sensory gating: Relationships with behavioral inhibition, attention, and working memory.
Lijffijt M, Lane SD, Meier SL, Boutros NN, Burroughs S, Steinberg JL, Gerard Moeller F, Swann AC. (2009).
Psychophysiology, 46, 1059-1068.
Severity of bipolar disorder is associated with impairment of response inhibition.
Swann AC, Lijffijt M, Lane SD, Moeller FG (2009).
Journal of Affective Disorders, 116, 30-36.
Behavioral assessment of impulsivity in pathological gamblers with and without substance use disorder histories versus health controls.
Ledgerwood DM, Alessi SM, Phoenix N, Petry NM (2009).
Drug and Alcohol Dependence, 105, 89-96.
Evaluation of behavioral impulsivity and aggression tasks as endophenotypes for Borderline Personality Disorder.
McCloskey MS, New AS, Siever LJ, Goodman M, Koenigsberg HW, Flory JD, Coccaro E F (2009).
Journal of Psychiatric Research, 43, 1036-1048.
Multidimensional assessments of impulsivity in subjects with a history of suicide attempts.
Wu C-S, Liao S-C, Lin K-M, Tseng MM-C, Wu EC-H, and Liu S-K (2009)
Comprehensive Psychiatry, 315-321.
Baseline neurocognitive profiles differentiate abstainers and non-abstainers in a cocaine clinical trial
Schmitz JM, Mooney ME, Green CE, Lane SD, Steinberg JL, Swann AC, and Moeller FG (2009)
Journal of Addictive Disorders, 28, 250-257.
Are personality and behavioral measures of impulse control convergent or distinct predictors of health behaviors?
Edmonds GW, Bogg, T, and Roberts, BW (2009)
Journal of Personality, 43, 806-814.
A test of alcohol dose effects on multiple behavioral measures of impulsivity.
Dougherty DM, Marsh-Richard DM, Hatzis ES, Nouvion SO, Mathias CW (2008).
Drug and Alcohol Dependence, 96, 111-120.
Interactive effects of sex and 5-HTTLPR on mood and impulsivity during tryptophan depletion in health people.
Walderhaug E, Magnusson A, Neumeister A, Lappalainen J, Lunde H, Resum H, Landro NI (2008).
Biological Psychiatry, 62, 593-599.
The effects of alcohol on laboratory-measured
impulsivity after L-Tryptophan depletion or loading.
Dougherty DM, Marsh DM, Mathiaw CW, Dawes MA, Bradley DM, Morgan CJ, Badaway AA (2007).
Psychopharmacology, 193, 137-150.
Behavioral impulsivity in adolescents with Conduct Disorder who use marijuana.
Dougherty DM, Mathias CW, Liguori A, Marsh DM, Dawes MA, Moeller FG (2007).
Addictive Disorders and Their Treatment, 6, 43-50.
Omega-3 fatty acid supplementation in patients with recurrent self-harm: Single-centre double-blind randomised controlled trial.
Hallahan B, Hibbeln JR, Davis JM, Garland MR (2007).
British Journal of Psychiatry, 190, 118-122.
Manic symptoms and impulsivity during bipolar depressive episodes.
Swann AC, Moeller FG, Steinberg JL, Schneider L, Barratt ES, Dougherty DM (2007).
Bipolar Disorders, 9, 206-212.
Impulsivity and Bipolar Disorder.
Najt P, Perez J, Sanchez M, Pelus MAM, Glahn D, Soares JC (2007).
European Neuropsychopharmacology, 17, 313-320.
Measuring impulsivity in adolescents with serious substance and conduct problems.
Thompson LL, Whitmore EA, Raymond KM, Crowley TJ (2006).
Assessment, 13, 3-15.
Reduced anterior
corpus callosum white matter integrity is related to increased impulsivity
and reduced discriminability in cocaine-dependent subjects: Diffusion tensor
imaging.
Moeller FG, Hasan KM, Steinberg JL, Kramer LA, Dougherty DM, Santos RM,
Valdes I, Swann AC, Barratt ES, Narayana PA (2005).
Neuropsychopharmacology, 30, 610-617.
Acute yohimbine increased laboratory-measured impulsivity in normal
subjects.
Swann AC, Birnbaum D, Jagar AA, Dougherty DM, Moeller FG (2005).
Biological Psychiatry, 57, 1209-1211.
Increased impulsivity associated with severity of suicide attempt history in patients with bipolar disorder.
Swann AC, Dougherty DM, Pazzaglia PJ, Pham M, Steinberg JL, Moeller FG (2005).
American Journal of Psychiatry, 162, 1680-1687.
Impulsivity in abstinent
alcohol-dependent patients: Relation to control subjects and type1-/type2-like traits.
Bjork JM, Hommer DW, Grant SJ, Danube C (2004).
Alcohol, 34, 133-150.
Suicidal behaviors and drug abuse: impulsivity and its assessment.
Dougherty DM, Mathias CW, Marsh DM, Moeller FG, Swann AC (2004).
Drug and Alcohol Dependence, 76s, s93-s105.
Laboratory measured impulsivity relates to
suicide attempt history.
Dougherty DM, Mathias CW, Marsh DM, Papageorgiou TD, Swann AC Moeller FG (2004).
Suicide and Life-Threatening Behavior, 34, 374-385.
Age at first drink
relates to behavioral measures of impulsivity: the immediate and
delayed memory tasks.
Dougherty DM, Mathias CW, Tester ML, Marsh DM (2004).
Alcoholism: Clinical and Experimental Research,
28, 408-414.
P300 event-related potential amplitude and impulsivity in cocaine-dependent subjects.
Moeller FG, Barratt ES, Fischer CJ, Dougherty DM, Reilly EL, Mathias CW, Swann AC (2004).
Neuropsychobiology, 50, 167-173.
Functional MRI study of working memory in MDMA users.
Moeller FG, Steinberg JL, Dougherty DM, Narayana PA, Kramer LA, Renshaw PF (2004).
Psychopharmacology, 177, 185-194.
Impulsivity in abstinent alcohol-dependent patients: Relation to control subjects and type-1/type-2 like traits
Bjork JM, Hommer DW, Grant SJ, Canube C (2004)
Alcohol, 34, 133-150
Impulsivity: A link between bipolar disorder and substance abuse.
Swann AC, Dougherty DM, Pazzaglia PJ, Pham M, Moeller FG (2004).
Bipolar Disorders, 6, 204-212.
Behavioral impulsivity paradigms: A comparison in
hospitalized adolescents with disruptive behavior disorders.
Dougherty DM, Bjork JM, Harper RA, Marsh DM, Moeller FG, Mathias CW,
Swann AC (2003).
Journal of Child Psychology and Psychiatry, 44, 1145-1157.
Validation of the Immediate and Delayed Memory Tasks in
hospitalized adolescents with disruptive behavior disorders.
Dougherty DM, Bjork JM, Harper RA, Mathias CW, Moeller FG, Marsh DM (2003).
Psychological Record, 53, 509-532.
Familial transmission of Continuous Performance Test behavior: Attentional and impulsive response characteristics.
Dougherty DM, Bjork JM, Moeller FG, Harper RA, Marsh DM, Mathias CW,
Swann AC (2003).
Journal of General Psychology, 130, 5-21.
Immediate and delayed memory
tasks: a computerized behavioral measure of memory, attention, and impulsivity.
Dougherty DM, Marsh DM, Mathias CW (2002).
Behavioral Research Methods: Instruments and Computers, 34, 391-398.
Comparison of women with high and low trait impulsivity using behavioral models of response-disinhibition and reward-choice.
Marsh DM, Dougherty DM, Mathias CW, Moeller FG, Hicks LR (2002).
Personality and
Individual Differences, 33, 1291-1310.
Reliability estimates for the Immediate and Delayed Memory Tasks.
Mathias CW, Marsh DM, Dougherty DM (2002).
Perceptual and Motor Skills,95, 559-569.
Two models of impulsivity:
Relationship to personality traits and psychopathology.
Swann AC, Bjork JM, Moeller FG, Dougherty DM (2002).
Biological Psychiatry, 15, 988-994.
Effects of moderate and high doses of alcohol on attention, impulsivity,
discriminability, and response bias in immediate and delayed
memory task performance.
Dougherty DM, Marsh DM, Moeller FG, Chokshi RV, Rosen VC (2000).
Alcoholism: Clinical and Experimental Research, 24, 1702-1711.
Alcohol increases commission errors for a continuous performance test.
Dougherty DM, Moeller FG, Steinberg JL, Marsh DM, Hines SE, Bjork JM (1999).
Alcoholism: Clinical and Experimental Research, 23, 1342-1351.
Immediate versus delayed visual memory task performance among schizophrenic
patients and normal control subjects.
Dougherty DM, Steinberg JL, Wassef AA, Medearis D, Cherek DR, Moeller FG (1998).
Psychiatry Research, 79, 255-265.
