carlsson (contemporaries. study for Sz) Flashcards
What are the aims of the study conducted by Carlsson?
Review evidence for and against the dopamine hypothesis
Consider other neurotransmitters e.g glutamate and serotonin
Explore new antipsychotics (to help with treatment resistance)
How many studies did Carlsson’s literature review include?
33 studies (32 published and 1 unpublished)
what do the sources, where he obtained his research, investigate?
variety of sources investigating neurochemical levels in patients diagnosed with Sz as well as studies into drugs known to induce symptoms of psychosis (amphetamines/ PCP)
what evidence do researchers also draw on?
studies into the effectiveness of drugs used to treat Sz
What types of studies did Carlsson review?
Brain scanning, animal studies, post-mortems, and human participant research
What conditions were studied in relation to schizophrenia (Sz) patients?
Patients in remission, in acute episodes, with positive and negative symptoms, and treatment resistant patients
how is generalisability high, using many types of Sz patients?
results about drug treatments for Sz can be representative of a wide range of patients
What is a potential weakness of the studies included in Carlsson’s review?
14 studies involved researcher bias as Carlsson was originally involved in them
What role does glutamate play in the development of psychotic symptoms according to the research?
Acts as an accelerator or a brake in dopamine regulation
What did Miller and Abercrombie discover in their studies on rats?
Reduced glutamate activity increases (accelerates) dopamine release (acting as an antagonist for NMDA receptors which glutamate binds with)
What is a limitation of using animal research in this context?
Anthropomorphic assumptions and differences in brain structure compared to humans
What was a strength of the procedure used in animal studies?
Strict control over the environment to accurately measure glutamate activity
What imaging techniques did Carlsson use to measure release of dopamine in the basal ganglia?
PET and SPECT scans
What did Laruelle find regarding amphetamine use and psychotic symptoms?
Amphetamine use enhances psychotic symptoms but doesn’t apply to all patients
What did Carlsson note about Sz patients in remission?
They only had normal dopamine activity
What issue do patients taking antipsychotics often report?
Complaints about side effects while their symptoms are in remission
What is a strength of using PET scans?
They provide quick, efficient, and objective data on brain function
What is a downside of PET scans?
Involves being injected with a radioactive tracer, which is invasive and may have unknown side effects
What conclusion did Carlsson reach about the excess dopamine as an explanation for Sz?
It is likely too simplistic. dopamine is easier to study in the brain than other NTs.
Which neurotransmitters are listed as likely related to Sz?
- Noradrenaline
- Serotonin
- Glutamate
- GABA
why do some patients respond better to some drugs than others?
because some patients’ Sz is more dopaminergic whereas others are more glutamatergic
Why might treatment resistant patients respond better to clozapine?
They may have a more glutamatergic condition, as clozapine targets serotonin instead of dopamine
What practical application does the study suggest for drug treatments?
More effective drug treatments should be developed focusing on other neurotransmitters
What do Sendt et al agree on regarding glutamate deficiency?
It is important for explaining positive symptoms such as hallucinations and negative symptoms such as apathy
