Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2007 Oct 8;90(2-3):183-92.
doi: 10.1016/j.drugalcdep.2007.03.005. Epub 2007 Apr 16.

Impaired time perception and motor timing in stimulant-dependent subjects

Marc Wittmann  1 , David S Leland, Jan Churan, Martin P Paulus
Affiliations

Impaired time perception and motor timing in stimulant-dependent subjects

Marc Wittmann et al. Drug Alcohol Depend. .

Abstract

Stimulant-dependent individuals (SDI) have abnormal brain metabolism and structural changes involving dopaminergic target areas important for the processing of time. These individuals are also more impulsive and impaired in working memory and attention. The current study tested whether SDI show altered temporal processing in relation to impulsivity or impaired prefrontal cortex functioning. We employed a series of timing tasks aimed to examine time processing from the milliseconds to multiple seconds range and assessed cognitive function in 15 male SDI and 15 stimulant-naïve individuals. A mediation analysis determined the degree to which impulsivity or executive dysfunctions contributed to group differences in time processing. SDI showed several abnormal time processing characteristics. SDI needed larger time differences for effective duration discrimination, particularly for intervals of around 1s. SDI also accelerated finger tapping during a continuation period after a 1Hz pacing stimulus was removed. In addition, SDI overestimated the duration of a relatively long time interval, an effect which was attributable to higher impulsivity. Taken together, these data show for the first time that SDI exhibit altered time processing in several domains, one which can be explained by increased impulsivity. Altered time processing in SDI could explain why SDI have difficulty delaying gratification.

PubMed Disclaimer

Figures

Figure 1
Figure 1. Model of multiple mediation effects
The independent variable X (stimulant dependence) affects the dependent variable Y (temporal-processing measure) either directly (c') or indirectly (ab path) via the mediators M1 to M4.
See this image and copyright information in PMC

References

    1. Arnsten FT, Li BM. Neurobiology of executive functions: catecholamine influences on prefrontal cortical functions. Biol Psychiatry. 2005;57:1377–1384. - PubMed
    1. Barkley R, Edwards G, Laneri M, Fletcher K, Metevia L. Executive functioning, temporal discounting, and sense of time in adolescents with attention deficit hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) J Abnormal Child Psychol. 2001;29:541–556. - PubMed
    1. Barratt ES. The biological basis of impulsiveness: the significance of timing and rhythm disorders. Person Indiv Diff. 1983;4:387–391.
    1. Barratt ES, Stanford MS, Dowdy L, Liebman MJ, Kent TA. Impulsive and premeditated aggression: a factor analysis of self-reported acts. Psychiatry Res. 1999;86:163–173. - PubMed
    1. Baxter LR, Jr, Schwartz JM, Phelps ME, Mazziotta JC, Barrio J, Rawson RA, Engel J, Guze BH, Selin C, Sumida R. Localization of neurochemical effects of cocaine and other stimulants in the human brain. J Clin Psychiatry. 1988;49:23–26. - PubMed

Publication types

MeSH terms