Stress Hormones, Cortical Control and Decision Making

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Stress Hormones, Cortical Control and Decision
Making
Israel Liberzon M.D. Theophile Raphael Professor
of Neuroscience, Professor of Psychiatry and
Psychology, U of Michigan Mental Health Service,
Ann Arbor VAMC
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Acknowlegments
Psychiatry, U of M Stephan Taylor, James
Abelson, Luan Phan, Robert Welsh Shaun Ho, Sarah
Garfinkel Psychology U of M Richard
Gonzales Psychology, Columbia Kevin Ochsner,
Tor Wager, Ed Smith
Disclosure and Conflict of Interest None
This work is supported by NIMH R24 MH075999
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Developing Translational Center University of
Michigan Columbia University Hypotheses 1.
Cognitive, emotional, and somatic (CES)
processes interact in reciprocally interconnected
feedback loops 2. Ineffective CES interaction can
lead to dysfunctional behavior and
psychopathology Strategy Using somatic
(cortisol) manipulations, we evaluated impacts in
the domains of memory and decision making using
neuroanatomical (fMRI), behavioral, and
neuroendocrine outcome measures
Appraisal, Memory and Decision Making
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Decision Making and Stress

• The curvature of the decision weighting function
  (?) is associated with
• DLPFC (Tobler, 2008)
• Ventral Striatum (Hsu, 2009)
• dACC (Paulus, 2006)
• The loss aversion is associated with
• VMPFC ventral striatum (Tom, 2007)
• Stress is known to affect decision making (e.g.
  Starcke, Wolf, Markowitsch Brand, 2008) and in
  turn decision making under risk can be stress
  inducing leading to cortisol release.
• Animal data suggest that high corticosterone
  (cortisol analogue) affects food choices (rats
  Teegarden and Bale 2008), aggressive food seeking
  and the ability to problem solve in the future
  (seabird chicks Kitaysky, Kitaiskaia, Piatt
  Wingfield 2003)
• To date, no study has investigated the
  neurocircuitry underlying modulation of decision
  making induced by cortisol.

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Limbic-Hypothalamic-Pituitary-Adrenal Axis
A system with a rhythm!
Adrenocorticotropin Hormone (ACTH)
A system that responds to challenges!

• Glucocorticoids- cortisol
• Mobilization of glucose from stores
• Mobilization of a.a. from protein stores
• Increase cardio-vascular tone
• Inhibit all other functions that are not
  essential for immediate survival

cortisol
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The Limbic-Hypothalamic-Pituitary-Adrenal Axis
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Loss Aversion fMRI Study by Tom et al. (2007)
Neural loss aversion should have Mixed Gamble
vs. the mean of Gains Only and Losses only
Gambles
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Non-Linearity of Decision Weighting Function
the Difference between Prospect Theory and EU
Theory - Hsu, et al 2009
Prospect Theory EU Theory
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Decision Making Task

• 40 subjects, 20 M, 20F (age 1837 years old,
  mean 22.7 yr)
• Treatment groups Hydrocortisone (100mg) (10 M,
  10 F)
• Placebo Group (10 M, 10 F)
• 2 Sessions for each subjects started at 1 or 2pm
• 1st session Decision Making Task at Baseline
• fMRI at 320 or 420 pm (100 min after oral
  intake)
• 2nd session Decision Making Task (Treatment
  effect)

3.89.8 seconds
Self-paced, lt 6000 ms, median 2.48 sec
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• Three types of trials Gains Only, Losses Only,
  Mixed (42 trials/type)
• Each trial has two gambles (left and right) each
  gamble has two possible outcomes (X, Y) each
  possible outcome has a probability (p, 1-p)

• Gains Only

Losses only
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Loss aversion (?)
Non-Mixed vs Mixed

Reward Discriminability (a)
Gains Only Value Function (v(x) xa, if x gt
0 v - ?xa, if x lt 0)
Probability Discriminability (?? )
All DM trials Decision Weighting Function (w(p)
dp? / (dp? (1-p)?))
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1st session Baseline 18 mins long
2nd session Treatment On 120 mins after drug
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Behavioral Results
Value Function (v(x) xa, if x gt 0 v - ?xa,
if x lt 0)
Value Function (v(x) xa, if x gt 0 v - ?xa,
if x lt 0)
In scanner
Cortisol Placebo
Baseline
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Behavioral Results contd
Decision Weighting Function (w(p) dp? / (dp?
(1-p)?))
Baseline
In scanner
Cortisol Placebo
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Cortisol and Decision Making

Cortisol
Striatum (Caudate and Putamen)

Insula
Amygdala/SLEA
Reduced probability processing
Reward processing sensitization
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Thank You