Knowledge clip
An explanatory model is a visual representation that organizes knowledge and helps you
explain how a certain behavior comes to be. In this explanatory model you can
distinguish between 3 types of factors: proximal, distal and ultimate factors
Proximal factors = person factors (beliefs) closest to outcome variable and have a direct
impact on the outcome variable
Distal factors = close contextual factors (behaviors/ ideas of friends or parents) can
influence outcome variable via proximal factors
Ultimate factors = distant contextual factors like policies, laws, availability of certain
substances. Influence outcome variable via distal or proximal factors.
Proximal factors = factoren die direct invloed hebben op de uitkomst, zoals
iemands overtuigingen/gedachten.
Distal factors = nabije omgevingsfactoren, zoals gedrag of ideeën van vrienden en
ouders. Deze beïnvloeden de uitkomst via proximal factors.
Ultimate factors = verre/maatschappelijke factoren, zoals wetten, beleid en
beschikbaarheid van middelen. Deze beïnvloeden de uitkomst indirect.
Hoorcollege 1 Introduction Risk Behavior and Addiction in Adolescence
Drug use among students in Utrecht is high. Last year, more cocaine was detected in the
city’s sewage than in 2024.
Risk behavior = Behaviors that pose a risk to a healthy physical, cognitive, psychosocial
development of adolescents
Substance use (e.g., smoking/vaping, alcohol use, cannabis use, use of illicit
drugs (e.g., XTC and other party/designer drugs)
Other risk behaviors (e.g., (online) gambling, gaming, social media use >
behavioral risk behaviors)
Addiction is the central theme
The general developmental proces of addiction:
Contact with a substance Experimenting with a substance Integrated use
Excessive use Addicted use
What we tend to regard as ‘risk behavior’ depends on…
Characteristics of the particular substance or behavior
o For instance, smoking/vaping versus gaming. First contact with
vape/cigarette > already risky for some groups. First contact with gaming >
not immediately seen as risky.
, Cultural and societal norms:
o Example: alcohol use in western versus Islamic cultures. Western society
> 1 glass is not seen as risk behavior. Only since 5 weeks > 1 glass seen as
risk behavior because of impact on health. Islamic cultures > 1 glass of
alcohol is already seen as risk behavior.
Advances in scientific knowledge:
o Example: knowledge on the risks of alcohol use for the development of the
adolescent brain
Predictors of risk behavior:
>> al behaviors (not only risk
behavior) develop based on capability, motivation and opportunity to engage in certain
behavior.
Need to relate information lectures to this model
The Behavior Change Wheel
Development during adolescence
Adolescence (+10 – 24 years)
Early adolescence (aged 10 – 14): physical growth, sexual maturation,
psychosocial development, social identity formation (likes by peers, bullied etc)
(girls start at 10/11, boys 12/13)
, Mid adolescence (aged 15 – 17): experimenting with (risk) behaviors, personal
identity formation. Personal identity formation is based on social identity
formation (question – how do you see yourself?, also more important to be
unique. Early adolescence: want to be similar to others, now more unique).
During mid adolescence experimenting with risk behavior becomes more
attractive.
Late adolescence (aged 18 – 24): practicing adult roles
Neurological development in adolescence
1. Strong growth in brain volume:
Decrease in grey matter (nerve cells, outer layer)
Increase in white matter (connections, inner layer) > communication between
brain cells is increasing.
Decrease in gray matter (nerve cells) among girls and boys by age
Process of pruning (snoeien): If you don’t use it, you lose it!
2. High plasticity and flexibility of the brain. Gaming > can gain a lot of skills but also
lose skills (social skills)
3. Increase in white matter: communication between brain regions strongly
improves
Long term memory increases
Capacity for abstract (critical) thinking and metacognition increases
The development of risk behavour shows an inverted U-shaped curve
Childhood low adolescence high adulthood low
Why? 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
This process is enhanced by testosterone
Control system (rational brain)
The rational brain develops slowly (until about 25 years)
The rational brain controls and enables executive functions/ skills: Risk
estimation, Monitoring long-term goals, Inhibition of 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)
The horse and rider metaphor
Horse = emotional brain, rider = control system
Control system: top-down processes, behavioral inhibition system (Also referred
to BIS)
Affective-motivational system: bottom-up processes, behavioral activation
system (also referred to BAS)
How can we define drugs or psycho-active substances?
Psychoactive substances are chemical substances that cross the blood-brain
barrier and affect the function of the central nervous system thereby changing
mood, perceptions, or consciousness (e.g., high/ euphoria, relaxation)
o Only talk about a drug when it crosses the blood-brain barrier, so
chocolate is not a drug because it doesn’t cross the blood-brain barrier.
Other characteristics of psychoactive substances:
o They often induce craving after (regular) use
o They often evoke loss of control after they have been used (regularly)
Psychoactive substances differ in
Type and strength of the psychoactive effect
The degree to which they elicit craving and loss of control
Most addictive substances: heroine, crack, nicotine
Types of drugs (based on their psychoactive effects)
picture!