Biological Assumptions Flashcards
What is the aim of the Biological Approach?
-Provides a physiological explanation for human behaviour
-Attempts to explain our behaviour in terms of physical factors within the body
Name the 3 Biological Assumptions.
-Behaviour can be explained by neurotransmitters
-Behaviour can be explained by localisation of brain function
-Behaviour can be explained by evolutionary influences
What is the 1st Biological assumption?
-Behaviour can be explained by neurotransmitters
What are neurons?
-The whole of the nervous system is composed of interconnected neurons
-Neurons= the cells found in the brain + nervous system
-They work by sending chemical + electrical messages to each other via small gaps between the neurons called a synapse
How fast/far do neurons travel?
-Neurones travel anywhere 1-200 miles an hour depending on the diameter of the particular axon + the thickness of the myelin sheath that covers the axon.
What are neurotransmitters?
-Messages that are passed from neuron to neuron by chemicals are called neurotransmitters.
-Neurotransmitters are chemical messengers that act between neurons within the brain.
-This allows the brain to process thoughts and memories
What are some examples of neurotransmitters?
-Serotonin- low levels= implicated in the aetiology of depression
-Dopamine- high levels= implicated in the aetiology of schizophrenia
-Oxytocin- used to stimulate uterine contractions in labor and childbirth
What is the 2nd Biological Assumption?
-Explain the biological assumption that behaviour can be explained by localisation of function
What does ‘Localisation of Brain Function’ mean?
-The organisation of the brain
-Specific areas of the brain have specific functions
-Behaviours are localised to areas of the brain.
-The brain is a complex structure: It controls everything about us: reflex actions, movements, thoughts, emotions
-The two halves of the brain are called hemispheres
What are the lobes of the brain and their names?
-The outer layer is known as the cerebral cortex, a deeply folded surface that covers four ‘lobes’:
-Frontal
-Temporal
-Parietal
-Occipital
What are the functions of each brain lobe?
-Frontal lobe: Personality planning, goals/decisions and language production.
-Parietal lobe: Motor area (controls voluntary movements) and somatosensory area (link between body and senses, e.g. response to pain, cold, heat) + spatial interpretation.
-Temporal lobe: Language centre (understanding of speech + producing speech which makes sense), processing auditory information, memory, transferring information from long term to short-term memory
-Occipital lobe: processing visual information - passing conclusions to the parietal and temporal lobes
What is the evidence for the Localisation of Brain Function?
-Damage to the temporal lobe: Wernicke’s area - Language
-Evidence through brain injury
-Understanding of Strokes
What is the impact of damage to the temporal lobe?
-Inability to comprehend language
-‘Wernicke’s aphasia’
-Symptoms of Wernicke’s aphasia: Production of nonsense words i.e. neologisms within the content of their normal speech.
What are two case studies for LoBF?
-Phineas Gage
-Henry Molaison
What happened to Phineas Gage?
-An iron rod went through his skull and damaged his cerebral cortex (left frontal lobe) resulting in a personality change. He survived for 13 years.
-Before= Sociable, , reliable and hardworking
-Afterwards= he was reported to be unpredictable, indecisive + used obscene language
-Damage to the neurons/tissue of the frontal lobe can lead to personality changes, difficulty concentrating or planning, + impulsivity
What happened to Henry Molaison?
-Had his hippocampus removed to stop his seizures
-After, Molaison suffered from anterograde amnesia.
-This led to him being unable to form and keep new memories, including recalling who he had just spoken with, new facts, or even learning new words
What is the 3rd Biological Assumption?
-Behaviour can be explained by evolutionary influences
What are the two types of Evolutionary Influences and what are they?
- Inherited:
-Origins of behaviour
-Genetic diversity
- Survival:
-Competition
-Adaptation
-Natural selection
-Traits
What is the Evolution of Behaviour?
- Charles Darwin said that all living things have evolved (adapted) over time through the process of natural selection.
-Darwin explained adaptation as the evolutionary process whereby living organisms becomes better suited to their environment.
-This process takes place over many generations, and is one of the basic phenomena of biology.
What is the theory of Natural Selection?
- any trait that increases the chance of survival or reproductive success will be naturally selected by evolution (stronger genes survive)
-Any trait that decreases the chance of survival or reproductive success will die out
(weaker genes do not survive)
What did Buss conclude about Mate Selection OVERALL?
-Concluded that mate preferences were universal rather than culturally dependent
-Preferences enable ‘continuation of the species’ by providing a stronger gene pool.
What did Buss conclude about Mate Selection for WOMEN?
Females for reproductive success = seek a high status male (wealth & profession).
-Would offer physical attractiveness ,fertility, chastity that would make her good potential mother material.
What did Buss conclude about Mate Selection for MEN?
Males for reproductive success = seek young (fertile) and attractive (good genes) females and
-Would offer resources + status (wealth and profession) to attract females, by showing that they are good providers
How is Nyctophobia linked to evolution?
-Sight = the dominant sense, if we cant see we could be in danger from predators.
-This is a potential threat to survival.
-Fight or flight response triggered
-Hypersensitive = anxiety = phobia
- Is a vital survival trait that has not disappeared (genome lag)
