Summary - Behavioural and cognitive neuroscience | 1 Ma Neuroscience | | Antwerp University

Behavioural and cognitive neuroscience
Personality:
Temperament: nature aspect of personality
 Inclinations we are born with
 Predisposition
 Differences in strength driving underlying basis emotions (fear, anger, disgust, surprise)

Character: nurture aspect of personality
 Emergent form developing through interaction of temperament and environment
 Habits we acquire over our lifetime
 Individual differences in a person’s goals and values
 Disposition

Personality = a unique combination of universal building blocks

History:
4 humours:
 Choleric (enthusiastic)
 Melancholic (somber)
 Sanguine (cheerful)
 Phlegmatic (calm)

Keirsey’s 4 temperaments:
 Guardians
 Rationals
 Idealists
 Artisans

Trait theory: ‘The big five’
 Extraversion: energy , positive emotions , …
 Agreeableness: compassion and cooperation towards others
 Conscientiousness: self-discipline, dutifulness
 Neuroticism: tendency to experience unpleasant emotions easily
 Openness: appreciation for art, emotion, adventure, …

Gordon W. Allport: psychologist
Omnibus definition: personality is everything that makes you an individual, integration and
interaction of your genetic inheritance and experiences
 No guidance on how to distinguish different personalities

Trait or integrative/ configurational approach: trait is a behavioural trend resulting from experience
and expressing the genetic predisposition of the individuals reaction to its surroundings

Systems or hierarchical approach: personality contains 3 layers of components; the persona, the self
and the unconscious processes
 Persona: external layers / mask you put on for different occasions
 Self: private ego behind the mask that dominates conscious experience (tied to memories)
 Unconscious processes: not accessible to conscious awareness

,C.R. Cloninger: psychiatrist + geneticist
 Made microbiological model of personality
o Twin and familiy studies
o Longitudinal development studies
o Neuropharmacology studies

Tridimensional personality questionnaire:
Tridimensional personality questionnaire: studies 3 dimensions/traits of personality based on 100
true/false questions
 Novelty seeking
 Harm avoidance
 Reward dependence

Disadvantages:
 Poor differentiation between personality disorders
 Neglects some personality disorders (paranoid , schizotypal personality)

Temperament and character inventory:
7-factor personality scale:
 4 temperament factors: novelty seeking, harm avoidance, reward dependence,
persistence
 3 character factors: self-directedness, cooperativeness, self-transcendence

TCI temperament cube:

Gaussian distribution: most behaviour is a balance between 2/more dimensions
 Personality disorders: extreme high/low variants

Sex differences:
 Harm avoidance + reward dependence: higher for women
 Novelty seeking + persistence: equal for both sexes

Quantify personality traits:
 Behavioural tests
 Neurochemical analysis

Novelty seeking:
Heritable tendency: toward intense excitement in response to novel stimuli, cues for potential
rewards and relief of punishment

Behavioural activation:
 Avoiding monotomy
 Pursuit of potential rewards
 Avoiding punishments

High novelty seeking: exploratory, adventure seeking, impulsivity, quickly distracted, …

Low novelty seeking: reflective, loyal, rigid, stoic, slow-tempered, introvert, persistent, …

Balance:
 Risk taking spirit, openness to changes, optimism, excitement about exploration
 Impulsiveness, extravagance, disorderliness, lack of focus

,Harm avoidance:
Heritable tendency: to respond intensely to aversive stimuli

Behavioural inhibition:
 Avoid punishment
 Avoid novelty
 Avoid frustrative non-reward

Balance:
 Cautiousness, careful planning
 Fear of uncertainty, extreme shyness, perfectionism, anticipatory worry, difficulty to relax

Reward dependence:
Heritable tendency: to respond intensely to signals of reward (verbal approval signals, sentiment, relief, …)

Behavioural maintenance: to maintain behaviour that was previously associated with rewards

Balance:
 Openness to warm communication, social sensitivity, attachment
 Dependence on approval, sentimentality

Neurotransmission:
Dopaminergic system:
Novelty seeking: uses dopamine for behavioural activation

Dopaminergic pathways:
 Nigrostriatal/ dorsal mesostriatal
 Mesolimbic/ ventral mesostriatal
 Mesolimbocortical
 Mesodiencephalic



Nigrostriatal pathway: part of basal ganglia motor loop
 Fluent coordination of limb movement
 Degeneration in Parkinson’s disease

Ventral tegmental area:
→ Projections to limbic structures (hippocampus, amygdala, septum): important for regulation
of emotional behaviour
→ Projections to neocortex (medial frontal, anterior cingulate, entorhinal): for motivational behaviour

Dopamine agonists: stimulation of dopaminergic neurons used for pharmacological evidence
 Increase of locomotor activity
 Feeling of joy and satisfaction
 Reinforcement of drug effects (addiction)

Dopamine antagonists: inhibition of dopaminergic neurons
 Ignoring stimuli
 Decrease spontaneous activity and speech (apathic behaviour)
 Decrease of associative ability
 Decrease of seeking behaviour

, Cholinergic system:
Basal forebrain nuclei: nucleus basalis of Meynert
 Nucleus basalis of Meynert quickly affected in Alzheimer’s disease

Brain stem nuclei: mesopontine tegmentum area , pontomesencephalotegmental complex

Acetylcholine: important for cognitive tasks
 Response to novel stimuli: arousal, attention, fear, stress, encoding novel stimuli
 Environmental habituation (recognition): learning processes
 Sleep

Noradrenergic system:
Reward dependence: uses noradrenaline for behavioural maintenance

Serotonergic system:
Harm avoidance: uses serotonin for behavioural inhibition

Neurotransmitter overview:
Catecholamines:
Precursor: DOPA
Neurotransmitters: noradrenaline, adrenaline, dopamine
Metabolite: DOPAC, HVA, MHPG

Indolamines:
Precursor: tryptophan
Neurotransmitters: serotonine
Metabolite: 5-HIAA

Behavioural tests:
Mice:
 Novelty seeking: naturally curious animals that like to investigate their environment
 Harm avoidance: mice avoid novel things as it could harm/endanger them

Holeboard test: amount of head dips and amount of different holes investigated measured

Canopy test: time spent in exposed zone VS time spent under canopy (roof)

Dark-light transition box: measure how quickly mouse enters bright compartment
and amount of time spent there

Elevated plus maze: time spent in closed arms VS time spent in open arms compared

Open field test: path followed and amount of time in centre VS time in corners compared
 Result: more motor activity during the first exploration

Neurochemical analysis:
Homogenate:
Homogenate: after homogenizing brain tissue all neurotransmitters present in the brain get measured
(neurotransmitters in vesicles too)
 Able to measure multiple brain regions
 Easier setup