The interplay between hormones and behavior:

• Hormones travel through the bloodstream, reaching areas beyond the scope of the nervous system
• Hormones regulate ongoing physiological processes BUT they do not directly influence behavior; rather, they alter the probability of specific behaviors in response to environmental stimuli
• For instance, it may be difficult for you to resist hormonal regulation, such as growth, but you can control your neural regulation
• Adrenaline | Cortisol | Oxytocin | Testosterone

Adrenaline

Adrenaline—Secreted by the adrenal glands, it triggers a heightened state known as an adrenaline rush in response to perceived threats or stressful situations, thus “fight-or-flight” response. This response includes increased heart rate, tense muscles, and enhanced oxygen intake, facilitating rapid action or confrontation.

Cortisol

Cortisol—Lundberg and Hellstrom (2002) found in saliva samples during the first 45 minutes after awakening, cortisol levels were 2X as high in women who regularly worked over 50 hours a week compared to those working a “normal” working week (35-40 hours per week). More than 200 women in a small Swedish city participated in this test.

Testosterone

Testosterone—a steroid hormone from the androgen group. In mammals, testosterone is primarily secreted in the sex organs of both males and females, although small amounts are also secreted by the adrenal glands.
Testosterone has been theorized to direct status-seeking/ competitive, behavior. Most studies in AQA/ IB/ Hodder books are topic specific, and google search unearthed more animal studies, So here’s a contemporary one by
Knight et al. (2022).

• Participants: 120 men aged 18 to 40 (n = 120) recruited via flyers and email lists
• Testosterone Administration: Topical gel applied to shoulders and upper arms under supervision
• Experimental Design: Half of the participants were told which treatment they were given (single blind), in order to emulate real-world environments in which testosterone is prescribed
  The other half of participants were only told they had an equal chance of receiving testosterone or placebo (double blind)
  This information was conveyed through a letter in a sealed envelope by assistants who were in the dark of which conditions participants were placed
• Competition Task: Mixed-gender math competition
• Measurement: Saliva samples collected to assess basal cortisol levels, before the competition and after the win/lose feedback
• Findings:
  • Testosterone with low cortisol levels associated with increased competition against male and high-status opponents (status-seeking)
  • Testosterone with high cortisol levels associated with increased competition against female and low-status opponents (status-loss avoidance)
• Conclusion: Supports a context-dependent dual hormone hypothesis, indicating testosterone’s role in competitive behavior contingent on cortisol levels and opponent status cues
• Significance: Provides insights into the interplay between hormones, cortisol, and social decision-making, contributing to our understanding of human behavior and social dynamics.

Read here for more on Neurotransmitters
Read here for more on the Nervous System

Source:

Knight, Erik L., et al. “The causal effect of testosterone on men’s competitive behavior is moderated by basal cortisol and cues to an opponent’s status: Evidence for a context-dependent dual-hormone hypothesis.” Journal of personality and social psychology 123.4 (2022): 693.

Lawton, Jean-Marc. Internal Assessment for Psychology for the IB Diploma: Skills for Success. Hodder Education, 2018.

Bryan, C., Halkiopoulos, C., & Giddens, P. (2018). Psychology. Pearson UK.