Psychology: Biological Core - Study Notes

Psychology Workbook: Biological Core 2025 - Study Notes

Introduction

• IB Psychology emphasizes understanding why individuals behave in specific ways.
• Obtaining a completely certain understanding of behavior is often impossible.
• Uncertainty is inherent, as knowledge has limitations and answered mysteries often lead to new unanswered questions.
• Canvas will provide weekly tasks for lessons and preparations, needing additional at-home work.
• A new student resource (workbook) is being tested, updated weekly with more material based on work from prior weeks.
• Regular resources include the Oxford IB textbook (Popov et al, 2017) and the INTHINKING website (https://thinkib.net/psychology).
• The course fosters a safe academic discussions on contentious topics, practical work, experiments, video analysis, and feature films.

Biological Core

• The biological core is one of the three distinct areas within the course and is followed by cognitive and socio-cultural cores.
• The biological core focuses on biological factors affecting behavior, including brain structure, neurotransmitters, hormones, and genes.
• Complex behaviors such as love, hate, friendship, and prejudice likely result from multiple factors, not just one, thus a holistic approach.
• In 1977, George Engel introduced the biopsychosocial model (BPSM).
• The BPSM considers 'bio' (biological factors), 'psycho' (cognitive factors/thinking), and 'socio' (upbringing/environment) elements.

Structure of the Brain

• The brain has the consistency of jelly.
• A healthy brain differs from one affected by Alzheimer's, which tends to be firmer and have air pockets.
• Localization of function partially explains how each part of the brain is responsible for certain functions.
• Nervous system which includes the spinal cord and the brain facilitates communication.
• The cortex, which covers the brain, has different parts associated with different functions created through evolution.
• The cortex is responsible for higher-order functions like abstract thought and voluntary action.

Cortex Sections

• The frontal lobes are involved in reasoning, planning, thinking, decision-making, voluntary action, and complex emotions.
• The parietal lobe deals with movement, orientation, perception, and recognition.
• The occipital lobe processes visual information.
• The temporal lobes manage auditory information, memory, and speech.
• Elements within the brain, such as a lobe, associate or involve certain functions, however they are not necessarily exclusive in their influence.

Parts of the Brain

• The cerebellum, resembling the cortex, coordinates movement and balance.
• The limbic system, known as the "emotional brain", includes multiple structures and is an older subcortical structure.
• The thalamus primarily handles sensory functions, serving as a hub for sensory organs before connecting to the cortex.
• The hypothalamus, located below the thalamus, affects emotion, thirst, and hunger.
• The amygdala is involved in memory, emotion, and fear.
• The hippocampus is crucial for learning, memory, short-term memory transfer, and spatial orientation.
• The brain stem, beneath the limbic system, manages vital processes like breathing and heartbeat and connects to the brain via the spinal cord.
• A deep furrow divides the cortex into left and right hemispheres, connected by the corpus collosum.
• In cases of epilepsy, the two brain sides can be divided by the corpus collosum.

Brain Damage and Dementia

• Brain damage is evident in boxing and possibly football.
• Louis Leborgne also known as "Tan" was studied by Broca (1861) and lost the ability to speak at age 30 with Broca's aphasia (loss of speech).
• Tan could only say "tan," and his autopsy at 51 revealed a lesion in the left hemisphere's frontal lobe (Broca's area).
• Wernicke discovered Wernicke's area in 1874, responsible for written and spoken language comprehension and is typically in the left hemisphere.
• Wernicke's aphasia impairs language comprehension and results in fluent but meaningless speech.

Further Studies on Brain Damage

• Sarah (Broca) and Byron (Wernicke) are examples of aphasia.
• Clive Wearing had a seven-second memory span due to illness, rather than injury.
• The Zika virus in Brazil caused retardation of brain growth.
• Seeing inside the brain via technology can assist in diagnosis and intervention.

A Personal Connection

• Those with Alzheimer's can have challenges finding the right words, putting sentences together, and memory loss.
• There can be a fleeting realization of what they should know, triggering upset.
• Dad's concept of time gets worse meaning less retention of information and changes with sleep patterns.
• Wilder Penfield mapped other brain areas using neuron stimulation and created a sensory and motor cortex map called the cortical homunculus.

Induced Brain Damage

• Karl Lashley conducted behavioral experiments on rats by inducing controlled destruction of parts of their brains to test for changes.
• Lashley failed to prove localization and concluded memory was distributed.
• Mass action indicates that the destruction percentage reduces performance regardless of location.
• Equipotentiality describes how one part of the cortex can take over functionality for other parts.
• Relative localization is supported by neuroscience for certain functions given certain conditions.

Split Brain Research

• The brain has two joined hemispheres principally via the corpus collosum, which directs electrical impulses from one side to the other (lateralization).
• Roger Sperry and Michael Gazzaniga researched this area.
• Epilepsy can be treated by severing connections at the corpus collosum.
• The two hemispheres function independently as shown in language, visual and emotional response, and cognitive capabilities.
• Following brain damage to a functional area, other areas can specialize in that area.

Neuroplasticity

• Neuroplasticity is a process by which the brain changes and grows throughout life, not just until adulthood.
• Synaptic connections reshape neural networks through creation and breakage.
• Neuroplasticity has multiple scales, from a single neuron (synaptic plasticity) to cortical remapping.
• The phrase "use it or lose it" translates to "neurons that fire together, wire together" in psychology.
• Key studies for remapping the sensory cortex show how the brain adapts, especially after physical changes.

Remapping the Sensory Cortex

• Merzenich et al (1984), used monkeys through a controversial and ethically debatable study since it uses animals.
• Researchers studied the representation of a monkey’s hand by mapping using Penfield techniques and amputating middle finger to see compensation.
• Compensation occurred in the brain as adjacent fingers took over the area where the finger was amputated.
• Neuroplasticity appears to be the core method of learning from environment.
• Draganski et al (2004) looked at structural changes when the brain really changes due to learning.

A Mechanism for Learning

• Draganski et al (2004) had each subject divided into juggling and non-juggling groups.
• As MRI scans developed juggling showed the development of more gray matter in specific areas and the area know to be coordination and movement.
• Change and amount performance depended on how consistent effort was.
• Growing areas decline with no practicing.

Further Evidence

• Draganski et al (2006) looked at intellectual learning shown in students preparing for exams reflected previous findings.
• The grey matter continued to grow.
• Maguire (2000) investigated London taxi drivers for navigational learning capacity through 'the knowledge."
• Maguire (2000) found that taxi drivers had the posterior hippoccampi larger and that more anterior hippocampal region bigger than control subjects.

Additional Studies on Neuroplasticity

• Adult learning in old age suggests neuroplasticity can continue and ward off dementia.
• There are studies by Chen and Goodwill (2022) and Gudlielman (2012) on aging.
• Olsewskaetal (2021) had musical training as useful research into neuroplasticity.
• Studies can reveal poverty, upbringing, restricted physical movement, and how strategic planning help develop spatial navigation.
• The Seligman and Maier study (1968) examines learned helplessness.

Hormones

• Hormones are chemical messengers that endocrine glands release, traveling in the bloodstream to target cells.
• They regulate ongoing processes like growth, metabolism, and reproduction and the behavior is whether hormones affect behavior.
• The nervous and endocrine systems are independent but also interdependent.

Hormone functions

• Adrenal glands use Aldosterone to regulate water balance and blood pressure.
• Adrenal glands (Corticosteroid) that control sugar levels and muscle strength.
• Pituitary gland (Oxytocin) stimulate uterus contractions and milk in the breast.
• Kidneys (Renin) use Angiotensin controls blood pressure and regulates production.
• Kidneys (Erythropoietin) use red blood cells.
• Pancreas (Glucagon) raises blood sugar.

Fight or Flight

• Fight or Flight describes the sympathetic and parasympathetic nervous system functions.
• Sympathetic functions as the gas pedal to respond to danger and the parasympathetic functions as the break to calm the body.
• Oxytocin performs the function to maintain close social bonds.
• Some changes activate/suppress various genes and hormones do to not influence behavior directly, instead they change the probability of behaviour.

Oxytocin

• Oxytocin known as the love, bonding, or cuddle hormone stimulates nipples to bond in mother and child.
• Romero’s experiment tested effect of oxytocin through a human animal study using humans and dogs to be placed in rooms and use cameras to engage interaction.
• Results described that oxytocin releases naturally and triggers the interaction.

Kosfeld Et al (2005)

• Kosfield Et al (2005) suggest oxytocin increases trust through economic games that use money to be invested or given as money transfers.
• Kosfield Et al (2005) proved that that oxytocin stimulates groups to be trusting through money transfers.
• Explanations can vary for this study as the experiment resulted in what was expected.

Scheele Et Al (2012)

• Scheele Et Al (2012) had experiments that showed that the face of oxytocin had been showing the moderating social distance between men and women.
• This experiments were conducted to not make women uncomfortable.
• Overall, most relations seem to effect behaviour, however the behaviour can be different as it alters.