Risk behavior and addiction
LECTURES
Lecture 1: An introduction to risk behavior and the development of
substance and behavioral addictions during adolescence
Substance use and addiction remain to be trending topics
How do we define Risk Behavior?
Risk behavior behaviors that pose a risk to a healthy physical, cognitive, psychosocial
development of adolescents
- Substance use (smoking/vaping, alcohol use, cannabis use, use of XTC and other
party/designer drugs)
- Other risk behaviors (gaming, (online) gambling, social media use)
Risk behavior can lead to addiction
General developmental process of addiction
1. Contact with a substance
2. Experimenting with a substance
3. Integrated use
4. Excessive use
5. Addicted use
Some risk behaviors develop faster into addiction than others.
What we tend to regard as ‘risk behavior’ depends on:
- Characteristics of the substance or behavior
o Some behavior is considered as risk behaviors in the second step, other
behaviors are only considered risk behavior in the fourth step
o Smoking/vaping vs gaming
- Cultural and societal norms
o Alcohol use in Western vs Islamic cultures
- Scientific knowledge
o Tobacco use or alcohol use has strict rules based on scientific knowledge
Predictors of (change in) risk behavior
All behaviors develop as a result of capability, motivation and opportunity
Which (neurological) developments take place during adolescence?
,Adolescence (10 – 24 years)
- Early adolescence (10 – 14): physical growth, sexual maturation, psychosocial
development, social identity formation
o Social identity formation: opinion of peers becomes important and helps to
form this identity
- Mid adolescence (15 – 17): experimenting with (risk) behaviors, personal identity
formation
o Personal identity formation: need to be a unique individual
- Late adolescence (18 – 24): practicing adult roles
Neurological development during adolescence
1. Rapid growth in brain volume
a. Increase in white matter
(connections)
b. Decrease in grey matter (nerve
cells)
i. More rapidly in girls. Girls
reached the peak earlier
than boys, so they decline
earlier than boys
2. High plasticity and flexibility of the brain
a. Pruning if you don’t use it, you lose it
b. Skills that won’t be used get lost. These could be important skills, like
social skills
c. Skills that are used, adolescence can become particularly good in them
3. Increase in white matter: communication between brain regions strongly improves
a. Long term memory increases
b. Capacity for abstract (critical) thinking and metacognition increases. Young
people become more critical of the outside world
c. “Country roads become highways” work more efficiently
Why is there a peak in risk behaviors during adolescence?
The peak in risk behavior follows an inverted U-shaped
curve. In mid adolescence, the peak is at its highest.
People must learn fast, have experience with a lot of
new situations and behaviors.
The speed of the development of two different brain
regions differs:
- The affective motivational system (emotional brain) develops fast
- The control system (rational brain) develops slowly
Affective-motivational system (emotional brain)
- The affective motivational system (reward center) is overactive during early and
mid-adolescence
- Adolescents experience stronger positive emotions than adults when they receive
or anticipate a reward.
o This process is enhanced by testosterone. It could be possible that because
boys have more testosterone, they are more involved in risk behavior.
Control system (rational brain)
- Develop slowly (until about 25 years)
- Plays a significant role in the development of executive functions:
o Risk estimation
o Monitoring long-term goals
, o Inhibit the tendency to respond to (short-term) possibilities for reward
(impulse control, behavioral inhibition, self-control)
The Maturational Imbalance Model
Increased risk-taking during adolescence is
a result of an imbalance between reward
sensitivity (the affective motivational
system) and impulse control (control
system). At some point, adolescence have a
high reward sensitivity, but not an equal
impulse control. As a result, the
adolescence may participate in risk
behavior.
Horse and rider metaphor: the horse (motivational sustem, bottom-up processes, BAS)
has its own way, want to do what he wants. But if the rider (control sustem, top-down
processes, BIS) is strong enough, he can control the horse. All kinds of behaviors are
inhibited or stopped.
What are psycho-active substances (drugs)?
Psycho-active substances chemical substances that cross the blood-brain barrier and
affect the function of the central nervous system thereby altering perception, mood, or
consciousness
- Induce craving after (regular) use (wanting to use it again)
- Evoke loss of control after they have been
used
Psycho-active substances differ in:
- Type and strength of the psychoactive effect
- The degree to which they elicit craving and
loss of control
For nicotine, the risk is the highest to develop
addiction after one has used the substance
Cannabis is a combination of a downer and hallucinogen. XTC is a combination of an
upper and hallucinogen.
How do we define addiction?
Sussman H1 (2017):
Intentional causal addiction process
Extensional classification of characteristics of an addiction
Substance use disorder (DSM-V)
Recurrent use over the last 12 months AND meeting at least two or more criteria (2-3
mild, 4-5 moderate, 6> severe SUD)
, Which implicit/automatic processes underlie the development of
addiction?
Two learning principles underlying the development of addiction:
1. Positive reinforcement occurs when the rate of behavior increases because a
desirable experience is resulting from the behavior
2. Negative reinforcement occurs when the rate of behavior increases because of an
aversive experience is prevented from happening
The neurobiology of withdrawal symptoms
Dopamine is not the only neurotransmitter that
plays a role in addiction.
The brain is starting to adapt to the use of a
certain substance. The sensitivity of the reward
is decreasing and the tolerance for the
substance is increasing.
This decrease in sensitivity of the brain reward system results from:
- Reduction in the number of dopamine receptors
- The existing dopamine receptors become less sensitive to dopamine
Resulting in:
- Tolerance
- Withdrawal symptoms (need for dopamine)
- A reduced sensitivity to natural incentives
o Reduced sexual interest in cocaine users because of becoming less
sensitive to dopamine
It is difficult to reverse these results. It depends on the kind of drug but takes a while
(years).
Associative learning
1. Drug use is having rewarding outcomes (= positive reinforcement)
2. Stimuli related to drug use (drug-cues) also get associated with its’ rewarding
outcomes
a. Location, time, attributes, people
3. Drug-cues itself become salient, because of its’ association with reward (incentive
salience)
Associative learning leads to two (implicit)
cognitive biases
1. Attentional bias individuals with
addictive behaviors develop an
(automatic) heightened attention towards
drug cues
2. Approach bias individuals with addictive
behaviors develop an automatic tendency
to approach, rather than avoid, drug-cues
Addiction an increasing imbalance between the affective-motivational and the control
system!