Lecture on the Endocrine System and Brain Functions

Endocrine System

• System of glands that secrete hormones affecting biological processes.
• Controlled by the hypothalamus in the brain.
• Key hormones and their functions:
  • Adrenaline: Activates fight-or-flight response, speeds up bodily processes.
  • Leptin: Involved in weight regulation, suppresses hunger.
  • Ghrelin: Increases hunger.
  • Melatonin: Triggers sleep and wakefulness.
  • Oxytocin: Promotes feelings of trust and bonding.
• Adrenal Glands: Produce adrenaline for fight-or-flight.
• Ovaries and Testes: Produce sex hormones; estrogen and testosterone.

The Brain

• Controls most human thought and behavior.
• Research on brain function is ongoing and complex.

Methods of Studying the Brain

• Accidents: Study of brain damage effects (e.g., Phineas Gage).
• Lesions: Destruction of brain parts, observe resultant behavior changes (e.g., frontal lobotomy).
• Electroencephalogram (EEG): Detects brain waves, used in sleep research.
• Computerized Axial Tomography (CAT): 3D image of brain structure.
• Magnetic Resonance Imaging (MRI): Detailed images using magnetic fields.
• Positron Emission Tomography (PET): Shows active brain areas during tasks.
• Functional MRI (fMRI): Combines MRI structure details with blood flow activity.

Brain Structure and Function

• Hindbrain: Life support, controls basic biological functions.
  • Medulla: Controls blood pressure, heart rate, breathing.
  • Pons: Connects hindbrain with midbrain and forebrain, controls facial expressions.
  • Cerebellum: Coordinates muscle movements.
• Midbrain: Coordinates simple movements with sensory information.
  • Reticular Formation: Controls body arousal and attention.
• Forebrain: Controls thought and reason.
  • Thalamus: Sensory signal relay.
  • Hypothalamus: Controls metabolic functions and biological rhythms.
  • Amygdala: Emotion experience.
  • Hippocampus: Memory processing.

Cerebral Cortex

• Surface layer of the brain, involved in complex thoughts.
• Divided into two hemispheres:
  • Left Hemisphere: Logic, language processing.
  • Right Hemisphere: Spatial, creative tasks.
• Further divided into lobes:
  • Frontal Lobes: Directing thought processes, language production (Broca’s area).
  • Parietal Lobes: Sensory information processing.
  • Occipital Lobes: Visual information processing.
  • Temporal Lobes: Auditory processing, language comprehension (Wernicke’s area).

Brain Plasticity

• Brain's ability to adapt and change.
• Younger brains more plastic, capable of compensating for damage.