Module4to7-The_Biology_of_Mind

Modules Overview

• Modules 4 to 7: Focus on the biology of the mind.

• Instructor: Dr. Erica Gelven

• Course: Psychology 1011

Biopsychology

• Definition: The scientific study of the links between biological and psychological processes.

• Key Specializations:

  • Neuropsychologists

  • Behavior geneticists

  • Biopsychologists

Neural Communication

• Essential topic in biopsychology understanding how neurons interact.

Neurons

• Definition: Basic building block of the nervous system.

• Main Components:

  • Dendrites: Short, branching extensions that receive messages.

  • Cell Body (Soma): Life-support center containing the nucleus.

  • Axon: Passes messages away from the cell body; may be covered in a myelin sheath.

Glial Cells

• Supporting cells in the nervous system that provide support, nourishment, and protection for neurons.

Dendrites

• Function: Receive and integrate messages from other neurons.

• Characteristics: Short and lack a myelin sheath.

Cell Body (Soma)

• Function: Acts as the cell's life-support center, containing the nucleus and supporting structures.

• Significance: Damage to the cell body results in neuron death.

Axons

• Function: Segmented extensions that pass messages through their branches.

• Characteristics: Long and may be myelinated for speed.

Myelin Sheath

• Definition: Fatty tissue layer that encases the axons of some neurons.

• Function: Increases the speed of neural impulses as they jump between nodes.

Action Potential

• Definition: A neural impulse generated by the movement of positively charged ions in and out of the axon membrane.

• Process::

  1. Neuron stimulation leads to a brief change in electrical charge.

  2. If strong enough, depolarization creates action potential.

  3. Changes propagate down the axon as adjacent areas depolarize.

Conduction of Neural Impulses

• Key Concepts:

  • Resting Potential: Positive charge outside; negative charge inside the axon.

  • Refractory Period: Brief resting phase post-neuron firing.

Threshold

• Definition: The level of stimulation required to trigger a neural impulse.

• Factors: Resulting from the balance of excitatory and inhibitory signals.

Communication Between Neurons

• Synapse: The junction between the sending neuron's axon tip and the receiving neuron's dendrites or cell body.

  • Synaptic Vesicle: Contains neurotransmitters.

  • Process: Neuron action potentials stimulate neurotransmitter release across synapses to the receptor sites on the receiving neuron.

  • Reuptake: Excess neurotransmitter molecules are absorbed back by the sending neuron.

Neurotransmitters

• Definition: Chemical messengers that cross synaptic gaps.

• Types and Functions:

  • Acetylcholine (ACh): Muscle action, learning, memory (linked to Alzheimer's).

  • Dopamine: Movement, learning, emotion; linked to schizophrenia and Parkinson's.

  • Serotonin: Mood, sleep, hunger; undersupply linked to depression.

  • Norepinephrine: Alertness/arousal; undersupply can lead to depressed mood.

  • GABA: Main inhibitory neurotransmitter; undersupply linked to seizures.

  • Glutamate: Main excitatory neurotransmitter involved in memory; oversupply can cause migraines.

  • Endorphins: Pain and pleasure regulation; oversupply from opiates suppresses natural production.

Nervous System

• Overview: Body's speedy electrochemical communication system consisting of the CNS and PNS.

• Central Nervous System (CNS): Includes the brain and spinal cord.

• Peripheral Nervous System (PNS): Connects the CNS to the rest of the body, including sensory and motor neurons.

Peripheral Nervous System

• Components:

  • Somatic: Voluntary muscle movements.

  • Autonomic: Controls involuntary actions of internal organs and glands.

    • Sympathetic: Arousing functions.

    • Parasympathetic: Calming functions.

Endocrine System

• Function: Slow chemical communication using hormones.

• Key Glands:

  • Pituitary: Master gland controlling other glands.

  • Adrenal Glands: Manage stress response.

  • Thyroid: Regulates metabolism.

  • Pancreas: Controls blood sugar levels.

Brain Structures

• Older Brain Structures: Brainstem controls automatic survival functions.

• Limbic System: Emotional processing and memory; includes amygdala and hippocampus.

• Cerebral Cortex: Involved in higher mental functions, with four lobes (frontal, parietal, occipital, temporal).

Brain Functionality

• Motor Cortex: Controls movement.

• Somatosensory Cortex: Processes sensory information.

• Visual Cortex: Processes visual information.

• Auditory Cortex: Processes sound information.

• Association Areas: Involved in complex functions such as learning and memory.

Corpus Callosum

• Definition: Connects the two brain hemispheres for communication.

• Split Brain: Condition resulting from severing of the corpus callosum, isolating the hemispheres.

Brain Imaging Techniques

• EEG, CT, PET, MRI: Various methods to visualize brain activity and structure.

Human Genetics

• Genetic Code: DNA as the carrier of genetic information.

• Key Terms: Chromosomes, genes, alleles.

• Genotype vs. Phenotype: Genetic makeup compared to physical characteristics.

• Patterns of Genetic Transmission: Homozygous, heterozygous, recessive, polygenic, multifactorial inheritance.