Love (Uppers)

These chemicals are typically associated with connection, trust, pleasure, and motivation toward others:

• Oxytocin – bonding, trust, social attachment

• Dopamine – reward, motivation, desire, reinforcement

• Serotonin – mood stability, contentment, social confidence

• Endorphins – pleasure, pain relief, warmth, comfort

• Vasopressin – pair bonding, attachment (especially long-term)

• Phenylethylamine (PEA) – early-stage attraction, excitement

• Endocannabinoids (like anandamide) – relaxation, mild euphoria, social ease

• Prolactin – nurturing behavior, post-bonding calm

Fear (Downers)

These are primarily involved in survival, vigilance, and responding to danger or discomfort:

• Cortisol – stress hormone, sustained alertness, energy mobilization

• Adrenaline (epinephrine) – fight-or-flight activation, rapid arousal

• Norepinephrine (noradrenaline) – vigilance, focus, anxiety, alertness

• Glutamate – excitatory signaling, often elevated in stress/anxiety states

• Substance P – pain perception, stress signaling

• CRH (corticotropin-releasing hormone) – initiates stress response cascade

• ACTH (adrenocorticotropic hormone) – drives cortisol release

• Dynorphins – dysphoria, stress, emotional pain

• Pro-inflammatory cytokines – linked to sickness behavior, low mood, fatigue

There are some overlapping chemicals, but I think you get the gist.