This projects research aim:
- The investigators aim to compare general and specific PIT effects in patients with
moderate to severe substance use disorder (Alcohol, Methamphetamine, Amphetamine and
Cocaine) and healthy controls using the newly developed (1st FP) full transfer task
and fMRI The investigators expect enhanced general PIT effects in patients compared
to controls at the behavioral level, and at the neuronal level enhanced
PIT-associated activations in the striatum, and lower activation in the prefrontal
cortex (e.g., dlPFC).
The investigators expect enhanced general PIT effects in patients with multiple SUD
compared to patients with single SUD.
The investigators expect increased behavioral and neuronal alcohol-specific PIT effects
in patients groups that also meet AUD criteria compared to controls and to patients
without AUD.
The investigators expect stronger behavioral and neural PIT effects (both general and
specific) to predict more substance use at 3-month follow-up.
Therefore, the investigators aim to conduct the Experiments with the following
Hypotheses:
Here the investigators assess on a behavioral and neural level a general and specific PIT
task by using the full transfer task which was developed in the 1st FP and allows the
assessment of both PIT tasks in one paradigm. This task consists of 4 parts: instrumental
training, Pavlovian conditioning, Pavlovian-to-instrumental transfer phase and query
trials to test participants' explicit knowledge.
The investigators will investigate HCs and three patient groups of high clinical
relevance: Patients with (1) AUD without comorbid SUD (cannabis, methamphetamine,
amphetamine or cocaine), (2) AUD with comorbid SUD (cannabis and/or methamphetamine
and/or amphetamine and/or cocaine), (3) SUD (cannabis and/or methamphetamine and/or
amphetamine and/or cocaine) without AUD. The investigators will recruit patients through
the addiction outpatient clinic of the Charité (mainly cannabis), the special outpatient
clinic for MUD at the University Hospital Dresden as well as the investigators' strategic
partner clinic in Radebeul und Städtisches Klinikum Dresden. Furthermore, the
investigators will be recruiting from the general population using advertisement. On
site, they undergo the comprehensive assessment implemented for the TRR cohort during the
1st FP. The full PIT paradigm is applied as described in Figure 3. Three months after the
examination, an online follow-up on the clinical course will be done by using
redcap-based questionnaires.
Methods:
WP1 will follow an ANOVA with four groups, including post-hoc group differences.
Functional imaging data will be conducted using a 3 T MR scanner to acquire gradient echo
t2*-weighted echo-planar images (EPI) and analyzed with SPM12. EPI images will be
preprocessed and analyzed as implemented during the 1st FP.
Expected results:
The investigators expect that general PIT effects are increased in all patient groups vs.
HCs. Moreover, the investigators expect that patients with AUD + comorbid SUD have
greater general PIT effects than patients with AUD alone. Concerning alcohol specific
PIT, the investigators expect that both AUD groups, but not patients with SUD without AUD
have greater effects than HCs. Moreover, the investigators expect that patients with AUD
- comorbid SUD have greater alcohol specific PIT effects than patients with AUD alone.
Concerning neuroimaging, the investigators expect greater activations in striatum and
reduced activation in the DLPFC during PIT in all patient groups vs. HCs. Moreover, the
investigators expect greater activations in striatum and reduced activation in the DLPFC
in patients with AUD + comorbid SUD as well as in patients with AUD alone. Of note, the
investigators expect similar neural activations during specific PIT in HCs and patients
with SUD without AUD.
Hypothesis 1a.:
General PIT effects are increased in all patient groups vs. HCs. Specifically, patients
with AUD + comorbid SUD will show greater general PIT effects than patients with AUD
alone. At the neuronal level patients will show enhanced PIT-associated activations in
the striatum, and lower activation in the prefrontal cortex (e.g., dlPFC).
Hypothesis 1b:
Concerning alcohol specific PIT, it is expected that both AUD groups, but not patients
with SUD without AUD have greater effects than HC. Moreover, patients with AUD + comorbid
SUD will have greater alcohol specific PIT effects than patients with AUD alone.
Moreover, the investigators expect greater activations in striatum and reduced activation
in the DLPFC in patients with AUD + comorbid SUD as well as in patients with AUD alone.
Hypothesis 1c:
The investigators expect that enhanced specific and general PIT effects are associated
with increased substance use at the 3-month follow-up.
Alternative strategies: In case of doubt about the extent to which gustatory alcohol and
juice rewards increase the PIT effect in subjects with comorbid SUD, the investigators
might alternatively develop and pilot a specific PIT paradigm with substance-related
pictures.