biological theory Flashcards
neurotransmitter
a chemical that passes messages around the brain from neuron to neuron
dopamine
a neurotransmitter
what is different about the brains of people with schizophrenia
there is too much of a neurotransmitter called dopamine in their brains. Dopamine is linked to behaviours such as movement, perception, attention, mood
what happens when there is too much dopamine
movements may become erratic and people will experience hallucinations and delusions
Messages from dopaminergic neurons that transmit dopamine fire too easily or often as they have unusually high numbers of dopamine (D2) receptors, resulting in more dopamine bindings and more neuron firing across the synapses. Explaining why they may see or hear things that do not exist
temporal lobe
corresponding parts of the brain that are responsible for functions such as seeing information, understanding speech and generating language
hippocampus
the part of the brain responsible for making new memories. It is important for forming semantic and autobiographical memories
evidence that shows brain activity increase schizophrenia
blood flow is lower in the frontal cortex region of the brain, and less frequently activated when certain tasks are carried out. The prefrontal cortex (control centre for the brain) and temporal lobe are smaller in volume, caused by a lack of grey matter.
They will lose control over their psychological functioning like planning ahead, being organised and making judgements
role of the hippocampus in the theory
it has a role of forming memories and emotions that go with them, it has a smaller volume in people with schizophrenia. the more severe the disorder, the more deflated this part of the brain is
criticism of biological theory (1)
By focusing on nature, the theory ignores the effect of nurturing on the development of schizophrenia.
Even if evidence shows that the brains of people with schizophrenia look and work differently, this is not enough to cause the disorder by itself. The brain still needs to interact with what is happening in the environment to be able to produce symptoms like hallucinations, delusions and disorganised speech.
criticism of biological theory (2)
It is possible that brain dysfunction is an effect of schizophrenia, not its cause.
Because a lot of evidence comes from investigating the brain using post mortems or scans after the diagnosis is made, researchers cannot be sure what came first. Brain function and brain structure may change after something else has triggered the disorder. In other words, brain dysfunction is like a symptom.
criticism of biological theory (3)
Critics say that the biological theory is too deterministic.
Schizophrenia may not be completely controlled by what is happening in the brain. People may choose to let their symptoms take over rather than trying to mentally control them. Critics say that it is pessimistic to see people with schizophrenia as having no free will. Is the biological theory really suggesting that people with schizophrenia cannot control their disorder at all? Saying they cannot control their disorder is quite pessimistic.
criticism of biological theory (4)
Critics say that the biological theory is too reductionist.
They argue that it is too simplistic to try to explain such a complex disorder by just looking at a part of the brain or one neurochemical. A number of different psychological factors may be working together to cause schizophrenia to occur rather than reducing it to one biological cause.
criticism of biological theory (5)
For some psychologists, ‘schizophrenia’ is too broad a label that covers a diversity of symptoms.
If this is true, it may not be realistic to look for a biological cause for something that may be partially constructed by society.
