<!-- TITLE: Neuroscience of Social Attachment, Rejection, and Competition --> <!-- SUBTITLE: --> # Hormones, behavior, and the brain (methods) > Chapter 3 in Harmon-Jones & Beer: Hormone Methods [So](https://en.wikipedia.org/wiki/Peptide) [many](https://en.wikipedia.org/wiki/Steroid) hormones... ## Pros and cons | Pros | Cons | |---------------|------------------| |sensitive to social stimuli;<br>non-invasive measurement;<br>hormones are important for behavior yo;<br> | low time resultion;<br>no 1-1 mappings; | ## The endocrine system, basics + Hormones affect behavior, but also vice versa + External stimuli $\to$ hormones + Hormones $\to$ behavior + Behavior $\to$ situation + Situation $\to$ hormones + Negative feedback loops control hormone levels + The brain (hypothalamous) monitors hormone levels. + If it detects an imbalance, it releases hormones which communicate with hormone-creating organs, and releases more of the target hormone + Thus, hormone changes reflect changes in cognition + There is no 1-1 mapping between cognitive states, hormone responses, and behavioral effects. + Having eaten a large meal and being scared both release cortisol + Hormones can have differential effects, depending on where they are released in the body, and the levels of other hormones + Various hormone systems interact (e.g. cortisol moderating the effect of testosterone on dominance-enjoyment) + "Phylogenic continuity" - patterns of hormonal reactions are stable across a wide array of mammals + Very high test-retest correlation of hormonal levels if at same time in cycles (even weeks after) + Low correlation between hormone levels and directed survey questions about aggression / competition / etc. + Hormones have been widely documented as having effects on behavior (e.g. testosterone and aggression) ## Worrying about confounders + Circadian rhythm $\to$ hormone levels + Morning or afternoon have different drawbacks and benefits + Mentrual cycle $\to$ hormone levels + Common to choose early follicular phase (between the third and the fifth day of the menses) + Drug status (e.g. birth control) $\to$ hormone levels We control by confounders either by doing all experiments at the same time of the day / month, or by trying to control numerically for the time of day / month. ## Measuring it + You can use saliva, blood, or spinal fluid (for hormone levels in the **C**entral **N**ervous **S**ystem) + Must be careful that the measurement itself doesn't affect hormonal levels + Lots and lots of details (kind of freezer, the gum to buy, etc.) + *Peptides* (specific types of hormones) are big enough that they don't pass through cell walls, and thus don't show up in saliva + radio(-)immuno(-)assay + immuno- use the immune response of an animal to what we're trying to measure + assay- measurement + radio - radioactive markers attached to these antibodies + in assays we want: + test-retest reliability # Hormonal signature of falling in love > Marazziti, D., & Canale, D. (2004). Hormonal changes when falling in love. Psychoneuroendocrinology, 29(7), 931-936. + 24 subjects who are in love [i.e. in love and in first 6 months of relationship] + 24 subjects who are either single or in long-lasting relationship [more than 6mo] + Pituitary, adrenal, gonadal hormones (8 in total) + Love $\to$ higher cortisol levels (no correlation with other hormones) + 12-24mo later retest $\to$ no correlation with any hormones + Testosterone showed changes in different directions for males and females, leading to zero overall effect Their interpretation is that initiation into a loving relationship is exciting, stressful, arousing. Falling in love heightens cortisol, they say. Some critiques: + Higher cortisol levels might induce love-falling [put a person with stranger on a rickity-bridge and see them fall in love] + Or those with higher baselines fall in and out of relationships (always "in love" with someone) + Missing the directional arrow # Cortisol moderates testosterone's effects on dominance-seeking behaviors > Mehta, P. H., & Josephs, R. A. (2010). Testosterone and cortisol jointly regulate dominance: Evidence for a dual-hormone hypothesis. Hormones and behavior, 58(5), 898-906. The title says it all here. High levels of cortisol can negate or *even reverse* the effects of testosterone on dominance-seeking behaviors. + Measurements between 11:30am and 4:30pm to minimize circadian effects. (isn't that a huge range?) + Study 1: leadership (observed qualities while leading) + Measure C&T before + Study 2: competition (defeat vs. victory) + Measure C&T before and after + Measured dominance based on whether they wanted to rechallenge after they lost + Just men + They basically just interpret the $C \times T$ interaction term + Basically, $\uparrow C_p + \text{loss} \to \downarrow T_a $ + Study 1 was correllated with study 2, apparently. # Rejection really hurts > Kross, E., Berman, M. G., Mischel, W., Smith, E. E., & Wager, T. D. (2011). Social rejection shares somatosensory representations with physical pain. Proceedings of the National Academy of Sciences, 108(15), 6270-6275. + Oh my god. They have the participants (who all were broken up with) look at a picture of their ex and think about the break-up. + What do we learn from knowing that the neural correlates of social rejection are the same as physical pain? Where do we get? Let's read the discussion for a clue. + Could this just be the pain from feeling such intense emotion? Are they trying to show that people get headaches when they get really sad, or that rejection literally hurts *prior to this*? + Why am I so critical of this paper, but accept the others relatively willingly? + If we want to know if it literally feels like pain, can we get closer than surveys? Can't we only know that these are the "neural correlates of pain" by asking the individuals how much it hurt? + [Secondary somatosensory](https://en.wikipedia.org/wiki/Secondary_somatosensory_cortex) and [insular](https://en.wikipedia.org/wiki/Insular_cortex) regions ## Implications. Why do we care? + Pain syndrome $\leftrightarrow$ bad relationship feedback + (Her suggestion) Poor feelings from social rejection dampened by Tylenol (*whaaaat*) # Oxytocin makes us trust more > Baumgartner, T., Heinrichs, M., Vonlanthen, A., Fischbacher, U., & Fehr, E. (2008). Oxytocin Shapes the Neural Circuitry of Trust and Trust Adaptation in Humans. Neuron, 58, 639-650. + Nasal double-blind consumption of [oxytocin](https://en.wikipedia.org/wiki/Oxytocin). + The treated "investor" did not lose trust in the "trustee" when they ran away with the money. They continue to trust them, even increasing in their trust. + The placebo "investor" loses a lot of trust, once the trust is broken. --- + Apparently there was a lot of hype around this hormone. They thought it was going to save the world, bring us all together, etc. But as usual it was all bullshit haha. + Interesting implication: daily/monthly cycle impactful, because this hormone has some impact on decision-making + Amazing how hormones can so drastically affect behavior, without our knowing it.