Credits
- Section Writer: Dr. Om J Lakhani
- Section Editor: Dr. Om J Lakhani

Support us:

1. Support you by Becoming a YouTube member (Click here).

   • Premium Membership- Download PDF version of Notes, Get ad free video and more
   • Consultant Membership- Above plus Download Powerpoint presentation of the notes

2. Support us by purchasing our book - Click here for more details:

   • Volume 1- THE BEST OF NOTES IN ENDOCRINOLOGY BOOK SERIES
   • Volume 2- THE BEST OF NOTES IN ENDOCRINOLOGY - DIABETES SPECIAL

3. For more such updates follow our WhatsApp Channel: https://whatsapp.com/channel/0029VaFyQnfHbFUz0LVdBO3h

• Q. What is the definition of love ?
  • An emergent property of an ancient cocktail of neuropeptides and neurotransmitters.
  • This definition emphasizes that love is more than just an emotion; it's a complex biochemical process involving various brain chemicals that influence our feelings and behaviors in the context of romantic attraction and attachment.
• Q. What is love from a biological perspective? (A summary)
  • From a biological perspective, love can be understood as a complex interplay of neurochemicals and brain regions that create and sustain the feelings and behaviors associated with romantic attachment. Here are some key aspects:
  • 1. Neurotransmitters and Hormones:
    • Dopamine: Often called the "feel-good" neurotransmitter, dopamine is heavily involved in the reward pathway of the brain. It plays a crucial role in the pleasure and reward experiences associated with love, especially in the early stages.
    • Oxytocin and Vasopressin: These hormones are linked to social bonding and attachment. Oxytocin, sometimes referred to as the "love hormone," is released in large quantities during intimate activities like hugging, touching, and sex. It promotes bonding and feelings of trust. Vasopressin is similarly associated with behaviors that produce long-term, monogamous bonds.
    • Serotonin: This neurotransmitter can influence mood and feelings of well-being. Interestingly, early stages of romantic love have been associated with decreased levels of serotonin, which might explain the obsessive thinking often seen in new relationships.
  • 2. Brain Regions:
    • Ventral Tegmental Area (VTA): This part of the brain is rich in dopamine neurons and is activated when people view photos of their romantic partners. It plays a significant role in the reward and motivation aspects of love.
    • Caudate Nucleus: Involved in reward detection and expectation, it is also active when people are in love, contributing to the feeling of reward and pleasure.
    • Anterior Cingulate Cortex and Insula: These regions are involved in feelings of empathy, social bonding, and emotional regulation. They play a role in the attachment and bonding aspects of love.
  • 3. Stages of Love:
    • Lust: Driven primarily by hormones such as testosterone and estrogen, lust is the intense craving for sexual intimacy.
    • Attraction: Characterized by increased dopamine and norepinephrine levels, attraction leads to the euphoria and energy often associated with falling in love.
    • Attachment: This stage is dominated by oxytocin and vasopressin, promoting long-term bonding and a sense of security and stability.
  • In summary, love from a biological perspective involves a combination of neurotransmitters, hormones, and brain regions that work together to create feelings of pleasure, attachment, and emotional bonding. This complex interplay not only promotes reproduction and pair bonding but also enhances the social cohesion necessary for human survival and well-being.
• Q. What is romantic love from evolutionary perspective ?
  • A collection of activities associated with acquiring and retaining emotions necessary for survival and reproduction.
  • These emotions change an individual's behavioral strategies in ways that increase their chances of achieving survival and reproductive goals.
  • Love serves as a means to promote and facilitate not only sexual reproduction but also the bonding and resource sharing necessary for raising offspring in many species.
• Q. What is the difference between human romantic love and mammalial courtship ?
  • Human Romantic Love:
    • Cross-cultural and universal, associated with specific physiological, psychological, and behavioral traits.
    • Begins with an individual recognizing another as special and unique, followed by focused attention and emotional investment.
    • Includes emotional dependence, empathy, sacrifice, and sometimes obsessive thinking.
    • Intense emotional and sexual possessiveness, mate guarding, and a stronger emotional union that can supersede mere sexual desire.
  • Mammalian Courtship:
    • Characterized by behaviors that increase the likelihood of reproductive success, such as increased energy, focused attention, and obsessive following.
    • Includes affiliative gestures, possessive mate guarding, goal-oriented behaviors, and motivation to win a preferred partner.
    • Mostly driven by biological and instinctual factors aimed at successful mating and propagation of the species.
  • Essential difference:
    • The difference is the human romantic love is different from sexual desire and supersedes those desires
• Q. What are three subtypes of behaviours which are often labelled as love and congruent with the same and what are the differences in them ? (Some people also call it stages of love)
  • The three stages of love are
    • 1. Lust
    • 2. Attraction
    • 3. Attachment
  • Here are the diagram summarizing them:
    • 
• Q. Can you summarize the role of hormones in each of these stages of love ?
  • Lust- Testosterone and estrogen are mainly involved
  • Attraction- Dopamine and norepinephrine are mainly involved
  • Attachment- Oxytocin and Vasopressin are involved
  • 
  • 
• Q. Is love and emotion or is it a motivation?
  • According to the article by Sheshadri , love is a motivation and not purely an emotion
  • It is a motivation to find companionship rather than to find sexual pleasure
• Q. What is the correlation between Stress and love ?
  • According to the article by Sheshadri et al, one of the key triggers for early phase of love is "stress"
  • Stress leads to seeking mating behaviour and enhances social interaction
  • There is also physiological increase of cortisol and central norepinephirine
  • Finding a mate and love leads to the release of oxytocin which relives this stress
  • 
• Q. Which is the 'cuddle' hormone ?
  • Oyxtocin
• Q. Is there a role of gonadal hormones in Love ?
  • This is a common misunderstanding
  • Gonadal hormones do have only a facilitatory role in love and is not the main player
  • Even those without gonadal hormones (hypogonadism) experience love
• Q. Do men and women have different regions of the brain involved in love?
  • There is a subtle difference
    • Men have more involvement of Right posterior dorsal insula - this is associated with response to youth and beauty
    • Women have more involvement of regions associated with attention, memory and emotions
  • These characteristics show that men and women have subtle difference in their priorities for seeking partners and companionship
• Q. Apart from human beings, which other animal shows remarkable monogamous relationship ?
  • prairie vole (Microtus ochrogaster) found in the grasslands of the US
  • 
• Q. What evolutionary advantage does monogamy provide to human beings ?
  • Humans have evolved to be monogamous because of the advantage it provides to the offspring in terms of biparenting
  • This is similar to what is seen in prairie vole
• Q. Is monogamy associated with any impact on the lifespan of human beings ?
  • Daoulah et al have concluded in an observational study the following:
    • "After adjusting for baseline differences, there was a significant association between polygamy and CAD (adjusted OR 4.6 [95% CI 2.5, 8.3]), multivessel disease (MVD) (adjusted OR 2.6 [95% CI 1.8, 3.7]), and left main disease (LMD) (adjusted OR 3.5 [95% CI 2.1, 5.9]). Findings were consistent when the number of wives was analyzed as a continuous variable. In conclusion, among married men undergoing coronary angiography for clinical indications, polygamy is associated with the presence of significant CAD, MVD, and LMD."
  • 
• Q. What is the relationship between arginine vasopressin (AVP) and male aggression ?
  • it is a complex relationship
    • AVP has been shown to promote defensive aggression in humans. Intranasal administration of AVP enhances the propensity for aggression at an individual level, particularly in contexts perceived as threatening
    • The effects of AVP on aggression can vary depending on the context and the type of aggression. For example, AVP infusion into the dorsal lateral septum (dLS) reduces aggression, whereas blocking the vasopressin V1a receptor (V1aR) increases aggression
• Q. What is the difference and similarity between love and addiction ?
  • Love and addiction seem to be attached to the same brain areas and hence there is a reward system also attached to love just like addiction
  • The difference is , however, unlike addiction love can have a feedback mechanism which can curtail and control the reward
• Q. Since the dopamine is involved here , what correlation do you find ?
  • Remember, the Dopamine is part of the reward pathway
  • The attraction stage is when there is involvement of dopamine
  • Meeting or being with the person you are attracted to activates the reward pathway making you feel better and reinforcement of this system
• Q. What is the role of serotonin in this ?
  • Serotonin levels actually reduce during the attraction phase
  • This is similar to what happens to people with Obsessive compulsive disorders
  • Hence there is an element of obsession with this
• Q. Does different stages / types of love impact different areas of the brain ?
  • Yes
  • As you can see from the picture below
  • 
• Q. Summarize the D.O.S.E hormones that deal with different aspects of happiness ?
  • 
• The Reward system
• 
• Q. Which is the brain's reward center ?
  • Right ventral tegmental area
• Q. What is the scientific name of the reward circuit ?
  • mesocorticolimbic ("reward") circuit
• Q. What is the role of Tegmental area ?
  • This is the collection center which when stimulated indicates presence of reward
  • On being stimulation it releases dopamine which go on act on two centers
    • 1. Mesolimbic system- stimulating the nucleus accumbens
    • 2. Mesocortical pathway - projecting into the prefrontal cortex which deal with the cortical aspects of the reward system
• Q. What is the role Nucleus accumbens ?
  • This is the main hub of the reward system
  • This collects and distributes the inputs
  • It circuits back to tegmental area to create a reinforcement and positive feedback system
  • Similar it circuits into the prefrontal cortex to again create a broader feedback loop
  • It projects into substantia niagra to look at long term aspect and generating reward seeking behaviours
• Q. Which are the excitatory and inhibitory neurons involved in the pathway ?
  • GABA- inhibitor
  • Glutamine and Dopamine- excitatory
• Q. What is dorsal and ventral striatum ?
  • The terms "ventral" and "dorsal" striatum refer to different regions of the striatum, which is a major component of the basal ganglia. The basal ganglia are a group of subcortical nuclei in the brain involved in motor control, emotions, and cognitive functions. Here’s how the ventral and dorsal parts differ:
    • Ventral Striatum: This includes the nucleus accumbens and parts of the olfactory tubercle. It is primarily involved in the processing of reward, reinforcement, and pleasure, as well as addiction behaviors. The ventral striatum receives dopamine projections from the ventral tegmental area (VTA), which are critical for the reward circuitry of the brain.
    • Dorsal Striatum: This area consists of the caudate nucleus and the putamen. It plays a key role in motor control and is also involved in various aspects of cognition and habitual behavior. The dorsal striatum is heavily involved in the processing and execution of movements, receiving extensive inputs from various parts of the cerebral cortex and projecting to other parts of the basal ganglia to modulate motor output.
  • The separation of these regions is not only anatomical but also functional, as they are involved in different neural circuits that affect diverse aspects of behavior and physiology.
• Q What is the role of sexual activity ?
  • Sexual activity tends to reinforce the love
• Q. What is the difference between the love and sexual activity ?
  • a) Sexual activity and drive is often quelled by the activity whereas love has a positive feedback loop and only increases
  • b) Sex drive can be with multiple partners, love is focussed towards one
• Q. Are there differences in area involved in romantic love versus maternal love ?
  • Yes
  • Maternal love- areas involved are:
    • Left ventral tegmental area
    • Left putamen
    • Left Substantia Niagra
    • Thalamus
  • Romantic
    • Right tegmental area- some say bilateral tegmental area involvement
    • Caudate nucleaus
    • Nucleaus accumbens
    • Hippocampus
  • The key difference seems to be the involvement of Nucleus Accumbens in romantic love vis-a-vis maternal love
• Q. Is dopamine available in limited quantities - do we run out of dopamine before we need to replenish it ?
  • Dopamine is not available in limited quantities in the sense that we “run out” and need to wait for replenishment. Instead, it is produced on demand and regulated by the body’s synthesis and recycling mechanisms.
  • Under normal physiological conditions, dopamine production can generally meet the brain’s needs.
  • However, certain stressors or diseases can impact dopamine levels, leading to the need for medical intervention to support dopamine synthesis and function.

• Q. Do we develop drug tolerance to dopamine?

  • Tolerance Mechanism: Yes, repeated drug use can lead to tolerance, where the brain's response to dopamine is diminished.
  • Receptor Desensitization: Dopamine receptors can become less sensitive or fewer in number with chronic stimulation.
  • Increased Dosage: Over time, higher doses of the drug are needed to achieve the same effect.
  • Neuroadaptation: The brain adapts to high levels of dopamine, leading to reduced natural dopamine production and release.
  • Withdrawal Symptoms: Abrupt cessation can cause withdrawal symptoms due to the brain's dependence on external dopamine stimulation.
  • Recovery: Tolerance can partially reverse with prolonged abstinence, allowing the brain to gradually restore normal dopamine function.
• Q. So does "doom scrolling" on social media create issues with dopamine ?

  • Yes

  • Short-Term Reward: Doom scrolling provides intermittent rewards, leading to frequent dopamine release.
  • Addictive Behavior: The unpredictable nature of content can create a compulsive checking behavior similar to gambling.
  • Reduced Sensitivity: Over time, the brain's dopamine receptors may become less sensitive, requiring more stimulation to achieve the same reward.
  • Mood and Anxiety: Excessive doom scrolling can negatively affect mood, increase anxiety, and contribute to stress, impacting overall dopamine balance.
  • Mental Health: Chronic engagement in this behavior can lead to reduced enjoyment in other activities and potential mental health issues.
• Q. Can this impact love ?
  • Yes
  • Reduced Attention: Excessive time on social media can reduce the time and attention given to a partner, affecting relationship quality.
  • Emotional Disconnection: Constantly engaging with negative content can lead to emotional exhaustion, making it harder to connect emotionally with a partner.
  • Dopamine Dysregulation: Overstimulation from social media can desensitize dopamine receptors, potentially reducing the pleasure and reward derived from romantic interactions.
  • Increased Stress: Higher stress and anxiety levels from doom scrolling can negatively affect relationship dynamics and communication.
  • Decreased Intimacy: Preoccupation with social media can decrease opportunities for meaningful interactions and physical intimacy with a partner.
  • In summary, doom scrolling can disrupt the balance of dopamine, leading to decreased attention, emotional disconnection, and increased stress, all of which can negatively impact romantic relationships.
• Q. Is there any research paper which has shown this ?
  • There is an Thesis by Williams et al which has has researched this topic. Here are the findings of the research
    • Purpose
      • To investigate how Facebook's affordances influence doomscrolling behaviors during the process of relational dissolution.
      • To understand if these behaviors affect the relational dissolution process.
    • Key Concepts
      • Facebook Affordances: Features such as ease of use, community, information seeking, escapism, and common interests.
      • Doomscrolling: Continuous scrolling and consumption of negative content, especially about past relationships.
      • Relational Dissolution Process: Stages that describe the breakdown of romantic relationships, including "grave-dressing" and "resurrection".
    • Research Questions
      • 1. Is an individual more likely to doomscroll if they have preserved digital artifacts from past relationships?
      • 2. Does doomscrolling impact the stages of relational dissolution?
      • 3. Do Facebook affordances perpetuate doomscrolling?
    • Methodology
      • Design: Cross-sectional study using an online survey.
      • Sample: 96 college students who have been in relationships and use Facebook.
      • Data Collection: Likert-based questions, multiple-choice questions, and one short answer.
    • Findings
      • Preserved Digital Artifacts: Individuals with preserved digital artifacts from past relationships are more likely to engage in doomscrolling.
      • Relational Dissolution Stages: Doomscrolling significantly impacts relational adjustment and increases Facebook jealousy. The more an individual doomscrolls, the harder it is to adjust to a new relationship.
      • Facebook Affordances: Community and escapism affordances positively correlate with doomscrolling, while common interests show a negative relationship.
    • Implications
      • Theoretical: Supports the updated relational dissolution model incorporating social media. Highlights the role of digital artifacts in relational dissolution.
      • Practical: Suggests that understanding social media's impact on relationships can help develop healthier media consumption practices.
    • Conclusion
      • Facebook's affordances significantly influence doomscrolling behaviors, affecting relational dissolution and adjustment processes. Understanding these dynamics can provide insights into managing digital relationships and mitigating negative online behaviors.
• Q. Are the brain areas involved in romatic love also involved in some other functions ?
  • Yes, the brain areas involved in romantic love are also involved in other functions. Here are some of the key brain areas and their additional roles:

  • 1. Ventral Tegmental Area (VTA)

  • Role in Romantic Love: Involved in the reward system, associated with the euphoria and pleasure of romantic attraction.
  • Other Functions:
    • Reward and Motivation: General involvement in the reward circuitry, activated by activities that are perceived as rewarding (e.g., eating, social interactions).
    • Addiction: Plays a significant role in the development of addiction to drugs and other substances.

  • 2. Caudate Nucleus

  • Role in Romantic Love: Associated with the reward system and goal-directed behaviors, active when thinking about a romantic partner.
  • Other Functions:
    • Motor Control: Involved in voluntary movement regulation.
    • Learning and Memory: Plays a role in habit formation and learning processes.
    • Emotion Regulation: Associated with emotional responses and the regulation of social behaviors.

  • 3. Anterior Cingulate Cortex (ACC)

  • Role in Romantic Love: Involved in processing emotional experiences and empathy, important for bonding and attachment.
  • Other Functions:
    • Pain Perception: Plays a role in the emotional aspect of pain perception (both physical and social pain).
    • Cognitive Control: Involved in decision-making, error detection, and conflict monitoring.
    • Emotion Regulation: Contributes to the regulation and processing of emotions.

  • 4. Insula

  • Role in Romantic Love: Important for emotional experiences, empathy, and awareness of bodily states, contributing to the feeling of love and attachment.
  • Other Functions:
    • Interoception: Involved in the awareness of internal bodily states (e.g., heartbeat, hunger).
    • Emotion Processing: Plays a key role in processing emotions such as disgust, fear, and empathy.
    • Addiction: Linked to the craving aspect of addiction.

  • 5. Hippocampus

  • Role in Romantic Love: Associated with the formation and retrieval of memories, including memories related to romantic experiences.
  • Other Functions:
    • Memory: Critical for the formation of new memories and the consolidation of short-term to long-term memory.
    • Navigation: Involved in spatial memory and navigation.

  • 6. Hypothalamus

  • Role in Romantic Love: Regulates the release of oxytocin and vasopressin, hormones important for bonding and attachment.
  • Other Functions:
    • Homeostasis: Regulates bodily functions such as temperature, hunger, thirst, and circadian rhythms.
    • Endocrine System: Controls the pituitary gland and regulates hormonal balance.
    • Behavioral Responses: Involved in responses to stress, aggression, and sexual behaviors.
  • These brain areas are part of complex neural networks that support a wide range of functions beyond romantic love, illustrating the interconnected nature of brain processes.
• Q. Cocaine is known to be extremely addictive, which area of brain does it target ?
  • Cocaine target the Ventral tegmentum and nucleas accumbens
  • These are also the key areas of romatic love as described earlier
• Q. Which narcotic drugs mimic the role played by Oxytocin ?
  • MDMA and GHB
• Q. What is the impact of serotonin on dopmine ?
  • Increase of sertonin levels reduce dopamine level
  • This is something that happens in patients on SSRI
• Q. What is relationship between impulsivity and drive and dopamine ?
  • Dopamine makes you more impulsive and gives you a greater drive while serotonin reduces impulsivity
  • 
• Q. Can you elaborate on the above ?
  • 1. Resting-State Networks (RSNs): RSNs like the sensorimotor network (SMN), salience network (SN), and default-mode network (DMN) show distinct patterns of connectivity and activity influenced by neurotransmitters.
  • 2. Dopamine's Influence: Dopamine (DA) signaling increases functional connectivity (FC) and activity in SMN and SN while decreasing it in DMN.
  • 3. Serotonin's Influence: Serotonin (5-HT) signaling decreases SMN activity and increases DMN activity.
  • 4. Neurotransmitter Pathways: The substantia nigra (SNc) and ventral tegmental area (VTA) pathways are key in dopamine's effects, while raphe nuclei (RNi) pathways are crucial for serotonin's effects.
  • 5. Psychiatric Implications: Altered neurotransmitter signaling can lead to functional reorganization of RSNs, contributing to conditions like bipolar disorder and schizophrenia.
  • 6. Behavioral Patterns: DA favors psychomotor activation and external focus, while 5-HT favors psychomotor inhibition and internal focus.
• Q. What are the effect of these hormones in various psychiatric states ?
  • Maniac state
    • There is reduced serotonin and hence relatively higher dopamine
  • Depressive state
    • There is reduced dopamine
    • Higher sertonin
  • Psychotic state
    • there is increased dopamine
  • 

References:
1. Seshadri KG. The neuroendocrinology of love. Indian J Endocrinol Metab. 2016 Jul-Aug;20(4):558-63. doi: 10.4103/2230-8210.183479. PMID: 27366726; PMCID: PMC4911849.
2. Daoulah A, Lotfi A, Al-Murayeh M, Al-Kaabi S, Al-Faifi SM, Elkhateeb OE, Alama MN, Hersi AS, Dixon CM, Ahmed W, Al-Shehri M. Polygamy and risk of coronary artery disease in men undergoing angiography: an observational study. International Journal of Vascular Medicine. 2017 Jan 30;2017.
3. Williams, Emma, "The Impact of Facebook Affordances on Doomscrolling Behaviors during the Relational Dissolution Process" (2022). Electronic Theses and Dissertations. 369. https://openprairie.sdstate.edu/etd2/369
4. Conio B, Martino M, Magioncalda P, Escelsior A, Inglese M, Amore M, et al. Opposite effects of dopamine and serotonin on resting-state networks: review and implications for psychiatric disorders. Mol Psychiatry. 2019;24(5):591-602.