Carlsson Et Al (2000)

Carlsson Et Al (2000)

1. ABOUT

   • Carlsson published a review to investigate the therapeutic implications from research on schizophrenia
   • AIM
     • To investigate further the relationship between levels of neurotransmitters on symptoms of schizophrenia
       • She believed that dopamine may not b the only neurotransmitter related to schizophrenia

2. METHOD

   • Looked at studies investigating neurochemical levels in patients
     • Evidence for high levels of dopamine inducing symptoms of psychosis from brain scans.
   • Looked at studies into drugs known to induce symptoms of psychosis
     • Evidence that linked amphetamines (which increase dopamine levels) to schizophrenia

3. FINDINGS

   • The neurotransmitter glutamate failing to be transmitted in cereal cortex related to negative symptoms
   • Glutamate failure in basal ganglia relates to positive symptoms
   • Clozapine is very effective at blocking activity of dopamine and serotonin. There is also fewer side effects

4. CONCLUSION

   • Schizophrenia may have different types that could be caused by abnormal levels of different neurotransmitters, and not just dopamine
   • Further research is needed to develop drugs that avoid negative side effects

5. EVALUATION

   • GENERALISABILITY
     • However, that time was 2000, nearly two decades ago. This study may be "time-locked" if research has moved on since then and it is no longer representative of the state of scientific ideas today.
   • RELIABILITY
     • The studies Carlsson et al. cite are all lab experiments, many of them on animals, which use modern PET or SPECT brain imaging techniques. These techniques are standardised and replicable, making the research reliable.
   • APPLICATION
     • The main application of this study is in the development of new antipsychotic drugs - improved dopaminergic drugs that have fewer side-effects based on a better understanding of dopamine pathways
   • VALIDITY
     • Carlsson is questioning the validity of the Dopamine Hypothesis. He also considers the Glutamate hypothesis
   • ETHICS
     • This is a review study so there are no ethical issues directly connected to it.
       • BUT, many of the studies Carlsson et al. cite are animal studies involving lab mice. These might involve ethical issues, since the mice are being injected with drugs to bring on psychotic symptoms.