The Biology of Love: Dopamine, Serotonin, and Oxytocin

The Biology of

Love

Learning Outcomes

B6: Using one or more examples, explain

the effects of neurotransmission on human

behavior.

Love Quotes Share your quote with your table and explain

why you chose it.

Discuss the following questions…

What do our quotes reveal about love? Are

there any common themes?

From your own experiences, are these quotes

accurate representations of love? Why or why

not?

What value does our society place on love?

The Science of Addiction

Key Questions:

What is the function of dopamine in regular

behavior?

What role does dopamine play in creating

addition?

What important ideas stand out to you

about addiction?

The Three Stages of Love Lust

Romantic Love

Attachment

Lust• The craving for sexual gratification.

Romantic Love

• Elation, heightened energy, mood swings, focused

attention, craving for emotional union with the

beloved, goal orientated behavior, and intense

motivation to win the preferred mate.

Increased Dopamine: Goal seeking behavior, increase

in energy, sleeplessness, craving, mood swings, etc.

Lowered Serotonin: Obsessive Thinking

Attachment The connection and feeling of content

when in proximity with your partner and

anxiety when separated.

Related to Oxytocin (Hormone)

Fisher et al (2003) Aim: To determine the neurological

activity of a person in love.

Method:

Participants: 7 Men, 10 Women. Between

the ages of 18-26. Average relationships of

7.4 months.

Placed participants in fMRI Machine

Showed a picture of an acquaintance,

asked them to count backwards to clear

mind, and then showed picture of their

beloved.

Fisher et al (2003) Continued

Findings: When looking at the

image of their beloved, participants

displayed activity in the area of the

brain called the VTA. This area is

part of the brain’s “reward system,”

and is rich in dopamine.

Conclusions: Dopamine plays an

essential role in shaping the feelings

of love.

Critical Thinking?

Marazziti et al (1999)Aim: To compare the brain

chemistry of a person in love with a

person with OCD.

Method:

20 Men & Women recently fallen in love.

20 Men & Women with OCD

20 Men & Women as a Control

Took samples of their blood and

measured levels of serotonin.

Marazziti et al. (1999)Finding: Men and Women with OCD

and those in love had similarly

lowered levels of serotonin.

Conclusion: Decreased Activity of

Serotonin contributes to a lover’s

obsessive thinking.

Critical Thinking?

Wrap Up: Your Love is My Drug What does this lesson reveal about Ke$ha’s

brain chemistry during this song?

How does this relate to addiction?

What stage of love is Ke$ha experiencing?

What advice would you give to Ke$ha if you

were one of her friends?

Warm-Up Part I: Taylor Swift

What biological functions are driving

T-Swift through this song?

How do the stages of love relate to the

color symbolism that Taylor sings about?

To what extent is the comparison

between love and addiction accurate?

Explain your thinking.

Example #2: Oxytocin Released by the pituitary gland.

Only exists in mammals.

Acts primarily as a neurotransmitter.

Involved in building bonds, trust,

generosity, and social memories.

The coolest hormone ever!

Scheele et al. (2013) Aim: To determine the role of oxytocin on

heterosexual male’s perception of their

romantic partners.

Method:

Repeated Measures Design

Treatment: Oxytocin Spray; Control: Placebo

Showed pictures of romantic partners and

measured their perceptions of partners

and brain activity using a fMRI

Scheele et al. (2013) Cont. Findings:

Oxytocin activated the reward (VTA) center in the brain to a greater extent.

Men on oxytocin perceived their partner more attractive than other women.

Oxytocin did not activate the reward system with acquaintances, only romantic partners.

Conclusions: Oxytocin play a key role in shaping monogamy and building bonds between lovers.

Critical Thinking?

Connections to major debates in Psychology?

Connections to other studies?

Feldman et al. (2012) Hormone: Oxytocin

Aim: To investigate the role of Oxytocin in early relationships in young adults.

Method:

Measured the oxytocin levels of 120 young adults (60 couples of 3 months) and 43 singles.

Measured oxytocin levels of the same participants six months later.

Feldman et al. (2012) Findings:

Oxytocin levels were higher for the new couples

than the single individuals.

High Oxytocin levels at the first test correlated

with couples staying together after 6 months.

High Oxytocin predicted more affectionate

touch, reciprocity, positive emotions, and

worries about the partner and relationship.

Conclusion: Oxytocin plays a key role in the

formation of new romantic relationships

among young adults.

Critical Thinking?

Ditzen (2013) Hormone: Oxytocin

Aim: To determine the impact of oxytocin

on couples’ communication.

Method: Had couples either spray

oxytocin or a placebo up their nose and

engage in a high stress conversation.

Ditzen (2013) Continued Findings:

Oxytocin improved communication and

lowered levels of cortisol.

Women: showed less social stress

Men: showed more social stress and were

more engaged in the conversation (Eye

contact, smiling, etc.)

Conclusions: Oxytocin impacts the ways

that couples communicate.

Critical Thinking?

Nakajima et al. (2014) Aim: To determine the role of oxytocin in

female rats interest levels in male rats.

Method: Gave a group of female rats a

chemical that blocked the receptor sites

of oxytocin in the frontal lobe.

Finding: The females showed almost no

interest in males and even showed equal

attention to a LEGO block.

Conclusion: Oxytocin is responsible for

sexual interest in female rats.

Critical Thinking?