3.4 Biological Influences on Behavior

Our bodies are complex machines, with chemicals and rhythms influencing how we feel and act. Neurotransmitters and hormones play crucial roles in regulating mood, emotions, and behavior. Understanding these biological factors helps explain mental health issues.

Circadian rhythms, our internal 24-hour clocks, impact sleep and overall well-being. Disruptions can lead to various disorders. Recognizing the biological basis of mental health allows for targeted treatments, from medications to lifestyle changes, improving quality of life.

Biological Factors and Human Behavior

Biological factors and human behavior

Top images from around the web for Biological factors and human behavior

• 

  Regulation of Hormone Production | Biology II View original

  Is this image relevant?

• 

  The Biological Domain | Introduction to Psychology View original

  Is this image relevant?

• 

  The Biological Basis of Mood Disorders – General Psychology View original

  Is this image relevant?

• 

  Regulation of Hormone Production | Biology II View original

  Is this image relevant?

• 

  The Biological Domain | Introduction to Psychology View original

  Is this image relevant?

1 of 3

Top images from around the web for Biological factors and human behavior

• 

  Regulation of Hormone Production | Biology II View original

  Is this image relevant?

• 

  The Biological Domain | Introduction to Psychology View original

  Is this image relevant?

• 

  The Biological Basis of Mood Disorders – General Psychology View original

  Is this image relevant?

• 

  Regulation of Hormone Production | Biology II View original

  Is this image relevant?

• 

  The Biological Domain | Introduction to Psychology View original

  Is this image relevant?

1 of 3

• Neurotransmitters act as chemical messengers transmitting signals between neurons in the brain and throughout the nervous system influencing mood, emotions, and behavior
  • Serotonin regulates mood, appetite, and sleep (depression, anxiety)
  • Dopamine associated with reward, motivation, and pleasure (addiction, schizophrenia)
  • Norepinephrine involved in alertness, arousal, and stress response (ADHD, PTSD)
• Hormones are chemical substances produced by endocrine glands released into the bloodstream regulating various physiological processes and influencing behavior
  • Cortisol, the stress hormone released by the adrenal glands, affects mood and immune function (Cushing's syndrome, chronic stress)
  • Testosterone, the male sex hormone, influences aggression and sexual behavior (hypogonadism, anabolic steroid abuse)
  • Oxytocin promotes social bonding, trust, and attachment (autism spectrum disorder, postpartum depression)

Endocrine system's influence on well-being

• Endocrine system consists of a network of glands producing and secreting hormones into the bloodstream regulating various physiological processes and influencing behavior
• Hypothalamus-pituitary-adrenal (HPA) axis involves the interaction between the hypothalamus, pituitary gland, and adrenal glands regulating the body's stress response and influencing mood
  • Chronic stress can lead to dysregulation of the HPA axis affecting overall well-being (adrenal fatigue, depression)
• Thyroid hormones produced by the thyroid gland regulate metabolism, energy levels, and mood
  • Imbalances can lead to mood disorders such as depression or anxiety (hypothyroidism, hyperthyroidism)

Biological Rhythms and Mental Health

Role of circadian rhythms

• Circadian rhythms are 24-hour internal biological clocks regulating various physiological processes synchronized with the light-dark cycle of the environment
• Sleep-wake cycle regulated by the suprachiasmatic nucleus (SCN) in the hypothalamus
  • Disruptions in circadian rhythms can lead to sleep disorders and affect alertness (jet lag, shift work disorder)
• Melatonin, a hormone produced by the pineal gland regulated by the SCN, plays a crucial role in regulating sleep-wake cycles
  • Light exposure suppresses melatonin production while darkness stimulates its release (seasonal affective disorder, delayed sleep phase syndrome)

Biological basis of mental disorders

• Neurotransmitter imbalances with abnormalities in levels or function can contribute to mental health disorders
  • Depression associated with low levels of serotonin, norepinephrine, and dopamine
  • Schizophrenia linked to excessive dopamine activity in certain brain regions
• Genetic factors with certain variations increasing the risk of developing mental health disorders through gene-environment interactions (bipolar disorder, autism)
• Pharmacological interventions targeting specific neurotransmitter systems can help alleviate symptoms of mental health disorders
  • Selective serotonin reuptake inhibitors (SSRIs) for depression and anxiety disorders
  • Antipsychotic medications for schizophrenia and bipolar disorder
• Non-pharmacological interventions such as psychotherapy like cognitive-behavioral therapy (CBT) can help address maladaptive thoughts and behaviors while lifestyle modifications including regular exercise and stress management techniques support mental well-being