It is suggested that acute stress shifts behavioral control from goal-directed, model-based toward habitual, model-free strategies.
We further use neurite orientation dispersion and density imaging (NODDI) to show that more goal-directed model-based learning (MBc) is also associated with higher mOFC neurite density and habitual model-free learning (MFc) implicates neurite complexity in the putamen.
However, stress is well known to promote habitual, model-free responses in humans and animals.
As such, a stronger VS BOLD PE signal is in keeping with more habitual, model-free learning.
We had observed that fluid IQ is associated with the VS BOLD PE signal, a putative signature of habitual (model-free) learning even when controlling for behavioral fit, which indicates how strongly the observed behavior is accounted for by PE-driven learning [ 13].
Trip purpose is commonly used in modeling habitual mode choice, especially for car trips.
c(Using Habitual Smoker Model of Repace & Lowrey (1985):assumes 2 cigarettes per smoker-hour & 1.43 mg RS P/cig: ETS-RSP = 650 Ds/Cv);d(excluding RSP and PPAH values from Pub #6).
This is in good qualitative agreement with previous research which shows that during smoking, the cigarette PPAH tracks the RSP, but has a higher decay rate [ 12]. Figure 4 plots the background-subtracted RSP vs. the background-subtracted PPAH values as a function of burning cigarette density and SHS-RSP air exchange rate using the habitual smoker model.
Stress has been shown to increase the habitual, or model-free, component of behavior [ 52].
The dependent variable in these models was the habitual mode choice (passenger car vs. public transport, which in the case of Thessaloniki currently amounts to bus).
These observations remained significant when multivariate logistic regression analysis was performed after the addition of therapeutic agents, the presence of diabetes complications, and risk factors for osteoporosis (e.g., smoking and habitual alcohol drinking) (model 3).
