Ockham's Razor and Understanding Behavior

Ockham's Razor

• When explaining something, assumptions should not be made
• Distinguishes between faith and reason
• Entities should not be multiplied unnecessarily
• Redundant information should be cut away, leaving only the essentials when explaining

Approaches to Understanding Behavior

• Hindsight (after-the-fact understanding):
  • A major limitation is past events can be explained in many ways, with no sure way to know which explanation is correct
  • Assumes a causal relationship
  • Often forms the foundation for further scientific inquiry, for instance, Darley and Latane's diffusion of responsibility explanation
• Understanding through Prediction, Control, and Theory Building:
  • Scientists should test the understanding of what causes a behavior whenever possible,
  • Understanding the causes of a behavior allows for prediction under specific conditions
  • A good theory incorporates existing knowledge, is testable, and its predictions are supported by research
  • It conforms to the law of parsimony, where simpler theories are preferred

World Views of Scientific Psychology

• Empiricism: Knowledge is acquired through senses, like observation and experience
• Realism: The world exists independently of human minds, beliefs, and wishes
• Materialism: Everything is part of the same spatiotemporal order and made of matter dealt with by physics; there's no spiritual realm beyond time and space
• Determinism: Every event is caused by an antecedent causal condition
• Anti-Reductionism: Scientific psychology should treat relations as real as the entities related

Misconceptions of Science

• Empiricism is not equivalent to experimentalism; to be scientific, one doesn't have to conduct an experiment
• Experimentation isn't the only legitimate form of research; observation, archival data, and theoretical research are also valid
• Testing a theory isn't just empirical; it also involves research or conceptual analysis like clarity and coherence of terms, variables, definitions, and hypotheses
• Science does not deal only with what is observable; it has always inferred unobservables from observables, progressing from such inferences

Psychology and Biology

• Biological aspects of behavior often occur outside of our awareness, such as clapping hands

The Nervous System

• A complex cell combination allows organisms to gain information and respond appropriately internally and externally
• Its three main functions are to receive information (input), process it, and guide actions (output)
• Responding to an alarm clock exemplifies these functions

Neurons

• Neurons are the basic building blocks of the nervous system, specialized cells that can be classified by function or shape

Neuron Categories by Function

• Sensory neurons collect information from sensory organs (eyes, ears, nose, tongue, skin)
• Motor neurons carry signals from the brain and spinal cord to muscles
• Motor neurons enable breathing, swallowing, movement, and speech
• Interneurons transmit signals between other neurons
• Sensory neurons are at work when touching a hot object and motor neurons work when removing a hand from the hot object

Neuron Shape and Structure

• Each neuron has a cell body, dendrites, and an axon
• The cell body, or soma, contains biochemical structures for neuron survival, and its nucleus carries genetic information
• Dendrites are branch-like fibers extending from the cell body, acting as specialized receiving units that gather messages from neighboring neurons

Neuron Cell Membrane

• A cell membrane covers all parts of a neuron, controlling chemical substance exchange and playing a critical role in nerve cell electrical activities
• A single axon extends from one side of the cell body, conducting electrical impulses away to other neurons, muscles, or glands

Axon Terminals

• The axon branches out into axon terminals, sometimes hundreds, connecting with dendrites from numerous neurons
• This allows a single neuron to pass messages to thousands of other neurons

Neuron Key Definitions

• Action Potential: The signal that travels along an axon
• Axon: The long slender nerve cell projection that conducts nerve impulses away from the cell body
• Axon Terminal (Synaptic Button): The small swelling at the end of an axon.
• Dendrite: The branched neuron projections that conduct impulses received from other neural cells
• Myelin: A whitish fatty substance covering axons, increasing information travel speed
• Neuron: The building block of the nervous system, also known as the nerve cell
• Neurotransmitter: The chemical signal allowing neurons to communicate with other neurons, muscles, and glands
• Soma: Derived from the Greek word for 'body,' it's the part of a neuron containing the nucleus
• Synapse: The junction between a neuron's terminal and another neuron, or a muscle/gland cell where nerve impulses pass

Glial Cells

• Neurons do not act alone; glial cells hold neurons together and facilitate communication
• Within the brain, glial cells outnumber neurons approximately 10:1

Two Classic Glial Cells:

• Microglia: Act as the main immune defense in the brain and spinal cord by removing damaged neurons, pathogens, and foreign substances
• Macroglia: Includes astrocytes, oligodendrocytes, Schwann cells, and ependymal cells, performing functions like regulating neuron communication, producing cerebrospinal fluid, and aiding neural development

Lecture Overview

• The topics covered are the nervous system, neurotransmitters, psychoactive drugs, and the endocrine system

Origins of Behavior and Mental Processes Stem From

• Biological Factors:
  • Genetic predisposition
  • Brain mechanisms
  • Hormonal influences
• Socio-cultural Factors:
  • Familial, societal, and cultural influences
  • Power influence
  • Group influence
• Psychological Factors:
  • Emotional response
  • Learned behavior
  • Cognitive ability
  • Perceptual ability
• Much of mental life is connected to our physical body per William James

Nervous System Communication

• Along a neuron occurs via an electrical impulse traveling down the axon terminal
• Communication from one neuron to another, muscle, or gland happens via neurotransmitters
• At the end, neurons release neurotransmitters to communicate with other neurons or glands

Nervous System Structure

• The CNS and PNS have different roles and subdivisions
• Peripheral Nervous System (PNS)
  • Includes all neural structures outside the brain and spinal cord
• Somatic Nervous System (SNS)
  • A system of sensory and motor neurons enables sensing and responding to the environment

Nervous System Function

• Sense organs send information to the central nervous system and carries information from the central nervous system to muscles
• Moving eyes to scan is an example

Autonomic Nervous System (ANS)

• The ANS senses the body’s internal functions and controls many glands and muscles
• Broken into sympathetic (pupils dilate) and parasympathetic (pupils contract) which act in opposing ways
• Examples include getting information from the brain to lungs, and involuntary activities like breathing and digestion
• Both systems work together to maintain an equilibrium

Neurotransmitters - Lock and Key Analogy

• Neurons receive information or are receptive to it, using chemicals as keys
• Receptors in the second neuron act as the lock
• Communication continues if the key fits into the lock
• Not all released chemicals fit into the next neuron
• Different neurons use different neurotransmitters

Neurotransmitter System

• A group of neurons that communicate using the same neurotransmitter

Excitatory Transmitter

• An effect that increases the likelihood of a neuron producing a neural impulse, however, it has to be sufficiently aroused
• For example, Glutamate is involved in all behaviors, importantly for memory and learning; an oversupply leads to seizures, an undersupply leads to psychosis

Inhibitory Transmitter

• An effect that lessens the likelihood of a neuron producing a neural impulse
• For example, gamma-aminobutyric is involved in motor activities
• Destruction of gamma-aminobutyric (GABA) leads to Huntington's disease and personality changes

Psychoactive Drugs

• Substances that, when consumed or administered, affect mental processes and behavior
• Examples:
  • Caffeine, alcohol, nicotine, meth/amphetamines, ecstasy, cocaine produce effects by increasing or decreasing neurotransmitter activity

Agonists and Antagonists

• Green is typically the sender while blue is the receiver
• Agonists: Fit into locks of neuro-receptors and will increase the effect of the neurotransmitter
• E.g., alcohol stimulates GABA activity, depressing neural activity, leading to depressed motor activity when consuming too much alcohol
• Antagonist: Decrease activity by blocking naturally occurring neurotransmitters from acting with the next
• E.g. Amphetamines boost activity of excitatory neurotransmitters dopamine and norepinephrine making people feel more emotionally aroused, cognitively alert, and social

Endocrine System

• Consists of glands that secrete hormones, distributed via the bloodstream

Hormone Function

• Hormones only act on cells with receptors for those hormones, serving as chemical messengers secreted from glands into the bloodstream
• Target organs are organs with receptors for a particular hormone
• The endocrine system is a slower communication means than the nervous system because blood flow is slower than nerve impulses
• Often both communication systems are used
• The pituitary gland is the master gland

Human Behavior Understanding

• Understanding human behavior requires an understanding of human biology
• Nervous system: Vast, complex, and high-speed communication network enabling people to gain knowledge and respond to the world
• The peripheral nervous system has many subdivisions, each with specialized, complementary functions
• Neurons communicate via electrical and chemical means
• Psychoactive drugs increase or decrease neurotransmitter action

Techniques for Studying Brain Function and Structure

• Originally only able to study people with/without traumatic brain injury
• Modern technology provides a multitude of ways to study the brain, and examines the structure/functionality
• Each modern brain-scanning technique has its advantages and disadvantages

The Central Nervous System (Reading)

• Consists of the brain and spinal cord
• The spinal cord:
  • Most nerves enter/leave the central nervous system by way of the spinal cord
  • Vertebrae protect spinal cord neurons
  • In cross-section central position resembles a H or butterfly
  • Has gray matter in the center, white matter on the outside
  • Sensory nerves enter back side, and motor nerves exit the front side
  • Spinal reflexes: Stimulus-response sequences triggered at the spinal cord level without brain involvement
• Example is touching something hot, can trigger sensory receptors which flash into the spinal cord and synapse inside the interneurons

The Brain

• Like the spinal cord, is composed of gray and white matter, however, the gray matter is on the outside, and vice versa
  • Made up different parts of the neurons, which make up the brain and nervous system as a whole
  • Gray matter is made up of the cell bodies of neurons
  • White matter is made up of the ling connecting parts of neurons, the axons

Autonomic Nervous System Summary

• Consists of sympathetic and parasympathetic divisions
• Sympathetic system has an arousal function and tends to act as a unit, while parasympathetic system slows down body processes and is more specific in its actions
• Together, maintain a state of homeostasis, or internal balance

Neuropsychology

• Investigates the effects of brain injury
• The effects study of traumatic brain damage on mental functions are often referred to as neuropsychology
  • Neuropsychological tests: Measure verbal and non-verbal behaviors of people who may have suffered brain damage

Electrical Recording

• Beyond measuring individual neuron activity, neuroscientists measure activity of larger neuron groups
• Offers the advantage of measuring large neuron group responses without invasive procedures
• Electroencephalography (EEG) measures large neuron group activity through scalp electrodes
• Magnetoencephalography (MEG): Uses the fact that a magnetic field is created each time an electrical current is created in a neuron or group- of neurons
• MEG records magnetic fields using an array of highly sensitive magnetometers (instruments for measuring very small magnetic fields) placed over the head

Brain Imaging - Magnetic Resonance Imaging (MRI)

• A strong magnetic field is passed through the brain and pulsed on and off causing molecules/atoms in the tissue to respond; once shut off molecules in the brain emit a radio signal which is then detected and mapped to provide images of the tissue
• Diffusion tensor imaging (DTI) measures how water molecules diffuse in tissue to gather information about how structures/pathways or tracts in the brain are aligned
  • Helpful for providing pictures of how white matter tracts are arrayed in the brain, telling us about how the brain is structurally connected

Functional MRI (fMRI)

• Uses the fact that oxygenated and deoxygenated blood respond to magnetic fields used with MRI scans differently
• When there is neural activity, more oxygenated blood is sent to that part of the brain
• Researchers investigate where the highest concentrations of oxygenated blood are being sent at any one time to deduce active parts when participants are undertaking a particular project

Positron-Emission Tomography (PET)

• PET scans measure where blood flows to in the brain
• Injection of radioactive glucose into bloodstream allows monitoring of glucose consumption by active neurons
• PET scans measure the energy emitted by the radioactive substance to map active brain areas

Functional Near-Infrared Spectroscopy (fNIRS)

• Shines near-infrared light into the brain and measuring its reflections
• fNIRS is non-invasive

Brain Stimulation

• An alternative to measuring neuron activity is to stimulate them and see what happens; can show what brain activity causes in various areas
• Collecting EEG or observing fMRI during a task only shows what neural activity is correlated with the behavior
• Causal relationships can be shown when intervening directly using interventions to the brain and measuring outcomes

Learning Objectives: Brains

• Discusses general facts about the brain, the story of Phineas Gage, central nervous system, brain structures/behavioral functions, hemispheric lateralization and plasticity

The Brain - General Facts

• Brain is mostly fat, with water, proteins, carbohydrates and salts:
  • An average brains weighs 1.3-1.4kg
  • It measures 140mm wide, 167mm long and 93mm high
• The Brain contains:
  • Folds i.e. gyri (gyrus = single fold)
  • Grooves i.e. sulci (sulcus = single groove)
• The area closest to the spinal cord is the oldest part of the brain that contains 1 billion neurons
• Electrical signals generate enough electricity to power a 12-watt light bulb

The Story of Phineas Gage

• Brain damage can lead to personality changes, and can lead to people who were calm/capable beforehand to be impulsive/having trouble regulating emotion or intellect

Basic Brain Structure

• Has the hindbrain which responsible for visceral functions
  • Heart rate
  • Breathing
  • Blood pressure
• Medulla and pons control vital life functions

The Pons and Medulla

• Pons: Involved in sleep and arousal, while the Medulla regulates vital functions for example, Pons can be involved in sleep and arousal and medulla regulates vital functions such as breathing and circulation
• Damage to the medulla or the pons can cause death, for example, high levels of alcohol can suppress medulla activity, leading to death by heart or respiratory failure
• There is crossover of the tracts of sensory nerves and tracts of motor nerves at the medulla That is, the left side of the brain is receiving sensory input and motor control over the right side of the body and vice versa

Cerebellum

• Coordinates fine muscle movement and balance- nicknamed "little brain"
• Contains more neurons than the rest of the brain
• Involved in riding a bicycle or piano playing in emotions, learning and memory
• Alcohol disrupts this, that causes people to find it difficult to coordinate reaching for something or walking in a straight line

Midbrain

• Processing auditory and visual responses

Reticular Formation

• Fibers that carries stimulation related to sleep and arousal through the brain stem
• Begins in the hindbrain, reaches into the midbrain
• A group of alerts incoming messages which admit or block sensory input when coming signal higher brain areas
• Blocks sensory input during surgery, for example, general anesthetics

Forebrain

• The major complex aspects of behavior and mental life, like thirst, hunger, memory, intelligence
• Cerebrum: Involved in sensing, thinking, learning, emotion, consciousness, and voluntary movement, with two large hemispheres that wrap around the brain stem

Thalamus

• the relay center for incoming sensory info, in each cerebral hemisphere, which signals and relays motor sensory, nicknamed a '"switchboard"
• Damage can lead to sensory problems like hallucinations, or motor problems such as tremors

Hypothalamus

• Regulated basic biological needs: hunger, thirst, temperature control which also, under the thalamus
• Connects to the pituitary gland and to the endocrine system, and plays a major role in motivation and emotion
• Controls many hormonal sections for example, sexual development or behavior

Suprachiasmatic Nuclei

• The brain's "timepiece," generates biological rhythms and is located at the back of the hypothalamus that generates biological timelines

The Limbic System

• Involved in motivation, emotion, and memory, to help coordinate behavior that satisfies emotional and motivational purges
• Hippocampus: Formation and retrieval of new memories, with damage may lead to problems in retrieving old ones.
• Amygdala helps to define and regulate emotions
  • Involved in fear and reward learning and functions through two emotional pathways
• Lower pathways bypass higher brain functions needed for life or death situations
  • Higher pathways include cognitive processing, and is related to aggression and fear

Cerebral Cortex

• Outer layer 0.63 cm thick
  • Mostly grey matter with unmyelinated cell bodies involved in: Higher-order thought, control of voluntary movements and complex aspects of behavior and mental processes

Four Lobes involved in:

1. Temporal lobe: Used for hearing, language, language
2. Frontal lobe: Used for thinking, problem solving, behavioral control, decision making
3. Parietal lobe: Used for perception object classification spelling, and knowledge of numbers
4. Occipital lobe: Used for vision and color blindness

• The knuckle is on the frontal, back is on the parietal, wrist is on the occipital while the thumb is on the temporal lobe

Lobes of the Brain and Cortices

• Four types of cortices: Motor, sensory, association, and the location of the lobes
• Motor cortex: Involved in voluntary body movements, larger areas that are devoted to parts of the body develop if they require greater complexity of movement
• Sensory cortex: Receives and processes stimulus information from the senses, in which greater surface area is devoted to amounts of area that alter through sensory input changes
• Association Cortex: It's not directly involved in either receiving sensory input or creating motor output Observational studies on individuals with traumatic brain injury has helped to understand the Association Cortex, for example:
• Broca's aphasia results in great difficulty speaking, speech is often grammatically incorrect
• Wernicke's aphasia results in problems with language comprehension, speech while possibly fluent, can have impaired meaning
• Broca’s area and Wernicke’s area are found on the side of the dominant hemisphere only

Hemispheric Lateralization

• The Cerebrum has two large hemispheres Lateralization has relatively greater localisation of a function in one hemisphere or the other to allow for communication

Hemispheres

• The two hemispheres communicate using the corpus callousum however, cutting the corpus callosum can reduce the effects of a form of epilepsy, known as split brain

Hemispheric Lateralization Split-Brain Studies

• In split-brain patients for example: Typically, the left hemisphere perceives stimuli from the right visual field and controls the right side of the body
• Conversely, the right hemisphere receives stimuli in the left visual field and controls the left side of the body when the corpus callosum is reserved

Plasticity in the Brain

• Neural Plasticity: The brain's ability for neurons, brain areas and networks to change in structure and function which is a recent discovery that neural connections can be

Modified

• Neural connections can be modified by experience, for example, premature babies
  • An example of a experience can produce changes in the motor cortex for those already skilled at a physical task, which sports psychologists ask athletes or visually practice mental rehearsal ways in which neurons can modify themselves: -> Change their structure or increase the number of transmitters they release -> New neurons can be created via neurogenesis -> Neural stem cells can mature into any type of neuron or glial cell needed by the brain

Brain Psychology Summary

• This involves a relation between the brain and its behavior which the parts of brain and nervous system, that works alone as opposed to other parts
• Multiple structure and associated functions, and studying split-brain studies can further help demonstrate hemispheric lateralisation and continue change across the lifespan

Forebrain Studies

• The most recently evolved part of the brain
  • The Cerebrum and its major structures contain two large hemispheres which are a left side and a right side, that wrap, an outer portion has cortex

Thalamus Studies

• It's the brain sensory switchboard, located above, the midbrain to sends signals to the visual, auditory and by the body senses balance

Theories of Personality

• Discusses what and how psychologists, and individuals seek to understand themselves and others, as it's and why it impacts and is needed

Personality:

• Personality is distinctive which it characterizes for example the enduring ways of thinking or feeling and acting that impact your responses to

The 4 Personality Groups Studies

• To better foster personal growth in others, while improving ones ability to understand themeselves

Study Attempts

Studies are based around different components unique components: -> What is a person to the other in a similar nomothetic manner -> The way persons might differ across idiographic focus, which includes descriptive and explanatory

Framework on how these levels work:

->General framework of why it is for better insight in the ways a persons thought actions align better under their nature ->Psychodynamic that explains it's an innate force ->Learning social learning framework that shows how it might affect

Key Study Frameworks and Figures:

->Frueds Model: Theories built off 23 volumes which included thoughts in both world and non-world senses Copernicus' - said, the earth holds a special place

• Drewin and Furde made changes saying, people don't have control of their minds

The ID

• Is unconious part, and the goal to get what might be considered as a socially impuslve impulse through desire.

the Ego

• Used to balance the internal parts with external forces like respecting social norms, but only within conscious forces

Frueds Theory

• Explains to show that by knowing these factors more can be more controlled within a person ->Used to explain a patients behaviors to help control Bandura is also known for his ability to better show why there is something like a personality given ->This is expressed because this can be used to better figure them from each other and why some will follow