Mod 4 (part1)

Introduction to Psychology: Neural and Hormonal Systems

• Module four of the Introduction to Psychology course focuses on neural and hormonal systems within the context of biology, behavior, and the mind.

• Important to understand the interplay between biological, psychological, and sociocultural factors that affect behavior.

Understanding the Brain and Mind Relationship

• The historical perspective of the mind:

  • Aristotle believed the mind resided in the heart.

  • Francois Gall's phrenology suggested that different brain areas correspond to distinct mental abilities and traits, a theory that was initially accepted but later debunked.

• Current biological psychologists utilize advanced technology to examine connections between neural (genetic, hormonal, neural) processes and psychological functions.

• Despite misconceptions, psychology is a scientific discipline deeply rooted in biological science.

Bio-Psycho-Social Systems

• Humans are considered bio-psycho-social systems:

  • Biological factors (genetics, neural, hormonal)

  • Psychological factors (thoughts, emotions, behaviors)

  • Sociocultural factors (environment, culture, family)

• The adaptive brain is shaped by experiences, leading to changes in neural wiring.

Neuroplasticity

• Neuroplasticity refers to the brain's ability to modify itself:

  • Critical during infancy and childhood, it involves reorganizing brain connections post-injury or trauma.

  • Brain changes through experiences, such as training in taxi drivers or musicians, showcasing enhanced spatial cognition and motor skills.

Neuron Structure and Function

• Neurons are the fundamental units of the nervous system:

  • Composed of a cell body, dendrites (branches that receive signals), and axons (long fibers that transmit signals).

  • Action potentials are electrical signals that propagate along the axon.

  • Chemical communication occurs between neurons at the synaptic gap.

Neuron Communication

• An all-or-none principle applies to neuron firing:

  • A minimum threshold must be reached to trigger an action potential, likened to the flushing mechanism of a toilet.

• Axons with a myelin sheath enhance speed of signal transmission by insulating electrical signals, aiding in quicker communication between neurons.

Neurotransmitters Overview

• Neurotransmitters are chemicals that facilitate communication across synapses.

  • They can either excite or inhibit the firing of receiving neurons.

• Examples of neurotransmitters:

  • Serotonin: Associated with mood regulation; disruption of its levels is linked to depression, treated pharmacologically with SSRIs like Prozac.

  • Dopamine: Impacts motor control and learning; deficiency is related to Parkinson's disease, treated with medications like L-DOPA.

  • Endorphins: Natural painkillers released during stress or exercise, contributing to sensations of euphoria.

Drug Interaction with Neurotransmitters

• Agonists: Enhance neurotransmitter functions (e.g., SSRIs increase serotonin availability).

• Antagonists: Block neurotransmitter actions and inhibit their effects.

Summary of Key Terminology and Concepts

• Familiarize with key terms and their definitions related to biology and neuroscience in psychology:

  • Neurons, synaptic cleft, action potential, myelin sheath, neuroplasticity, etc.

• Understanding these concepts is vital to grasp psychological phenomena and their biological underpinnings.