It is well known that use of the drug cannabis can induce subjective distortions of perception in several sensory modalities. However, few direct examinations of the neural effects of cannabis use on early sensory processing have been undertaken, particularly utilizing novel electrophysiological techniques. The overall aim of the current proposal is to examine whether current cannabis users demonstrate deficits in neural synchronization as measured by electroencephalographic (EEG) entrainment to periodic auditory and visual stimulation. Subjects will passively observe periodic sensory stimuli (auditory click-trains (10, 20, 30, 40, and 50 Hz) and photic flickers (8, 13, 18, 25, and 38 Hz) while EEGs are recorded. The ability of the resulting steady-state potentials to synchronize to the specific frequencies of stimulation will be assessed via EEG power, signal to noise ratio, and intertrial coherence. In addition, EEG synchronization during perceptual binding will be assessed utilizing an induced gamma paradigm (moving dot stimuli using Random Dot Kinetograms). Several clinical interviews and psychometric questionnaires will also be administered in order to determine possible relationships between EEG brain measures and the perceptual correlates of cannabis use. It is hypothesized that during the entrainment paradigms cannabis users will exhibit decreased EEG power, signal to noise ratio, and intertrial coherence at the frequencies of stimulation across sensory modalities. It is also predicted that during the induced EEG paradigm, cannabis users will exhibit decreased gamma-band (~ 40 Hz) activity during the perception of coherent moving dots. It is hypothesized that these deficits in EEG neural synchronization will correlate with psychometric measures such as schizotypal personality and perceptual aberration, as well as urinary measures of cannabis metabolites. Taken together, this data may serve to elucidate whether the known cognitive dysfunction observed in cannabis use is in part related to disturbances in early sensory information processing and/or neural synchronization.

Agency
National Institute of Health (NIH)
Institute
National Institute on Drug Abuse (NIDA)
Type
Small Research Grants (R03)
Project #
1R03DA019630-01A1
Application #
7037727
Study Section
Neural Basis of Psychopathology, Addictions and Sleep Disorders Study Section (NPAS)
Program Officer
Gordon, Harold
Project Start
2005-09-30
Project End
2007-08-31
Budget Start
2005-09-30
Budget End
2006-08-31
Support Year
1
Fiscal Year
2005
Total Cost
$75,750
Indirect Cost
Name
Indiana University Bloomington
Department
Psychology
Type
Schools of Arts and Sciences
DUNS #
006046700
City
Bloomington
State
IN
Country
United States
Zip Code
47401
Skosnik, Patrick D; Krishnan, Giri P; D'Souza, Deepak C et al. (2014) Disrupted gamma-band neural oscillations during coherent motion perception in heavy cannabis users. Neuropsychopharmacology 39:3087-99
Fridberg, Daniel J; Skosnik, Patrick D; Hetrick, William P et al. (2013) Neural correlates of performance monitoring in chronic cannabis users and cannabis-naive controls. J Psychopharmacol 27:515-25
Skosnik, Patrick D; D'Souza, Deepak C; Steinmetz, Adam B et al. (2012) The effect of chronic cannabinoids on broadband EEG neural oscillations in humans. Neuropsychopharmacology 37:2184-93
Fridberg, Daniel J; Vollmer, Jennifer M; O'Donnell, Brian F et al. (2011) Cannabis users differ from non-users on measures of personality and schizotypy. Psychiatry Res 186:46-52
Edwards, Chad R; Skosnik, Patrick D; Steinmetz, Adam B et al. (2009) Sensory gating impairments in heavy cannabis users are associated with altered neural oscillations. Behav Neurosci 123:894-904
Skosnik, Patrick D; Edwards, Chad R; O'Donnell, Brian F et al. (2008) Cannabis use disrupts eyeblink conditioning: evidence for cannabinoid modulation of cerebellar-dependent learning. Neuropsychopharmacology 33:1432-40
Edwards, Chad R; Skosnik, Patrick D; Steinmetz, Adam B et al. (2008) Assessment of forebrain-dependent trace eyeblink conditioning in chronic cannabis users. Neurosci Lett 439:264-8
Edwards, Chad R; Skosnik, Patrick D (2007) Cerebellar-dependent learning as a neurobehavioral index of the cannabinoid system. Crit Rev Neurobiol 19:29-57
Skosnik, Patrick D; Krishnan, Giri P; O'Donnell, Brian F (2007) The effect of selective attention on the gamma-band auditory steady-state response. Neurosci Lett 420:223-8