A) Clinical studies in first episode and chronic schizophrenia
'Their lives are being ruined twice over – by the
illness and by the drugs used to treat it.'
Cliff Prior, Director of the National Schizophrenia Fellowship
on the use of typical antipsychotics on people with schizophrenia
- August 1999
While some symptoms of schizophrenia can be controlled
by the older-style antipsychotics such as haloperidol, many
patients have to endure painful and stigmatising side-effects
as a consequence of these treatments. In addition, these
drugs do not help 30% of people with schizophrenia and they
do not improve cognition - our ability to remember, make
plans and take decisions - or negative symptoms - the apathy,
social withdrawal and lack of emotion found in people with
schizophrenia. Recently, newer (or 'atypical') antipsychotic
drugs have been developed. These drugs do not have such
severe side-effects, and have been shown to improve schizophrenia's
cognitive and negative symptoms. The use of these newer
drugs in the UK, however, is restricted and there is still
a lot to learn about how they affect brain function.
In the Clinical Neuroscience Research Centre, researchers
are investigating the effects of newer antipsychotics on
symptoms, memory, planning and decision-making skills and
the impact of the disease on their family. Recent findings
from the Centre's brain imaging research1 into drugs effects
on brain function have revealed that newer antipsychotics
can restore activity to the crucial part of the brain.
B) Psychological features of schizophrenia - behaviour and
Cognition in schizophrenia
Schizophrenia is commonly associated with bizarre thoughts
and invisible voices. But, it is now recognised that problems
in cognition - reduced attention span, problems with memory
and difficulties in reasoning and problem solving - are
core features of schizophrenia and are believed the most
important factor for poor outcome in people with schizophrenia.
Memory is particularly impaired in people with schizophrenia.
Researchers in Clinical Neuroscience Research Centre are
investigating the characteristics and the neural correlates
of cognitive impairment in people with chronic schizophrenia
and those experiencing their first episode of psychosis.
Mental state attribution
Normally, we find out information about someone by how they
express themselves, not just by what they actually say.
People with schizophrenia, however, often fail to detect
what someone may be feeling from their expression or from
the way they say something. In a study of mental state attribution,
people with schizophrenia were required to attribute an
emotional state to facial expressions when only the eyes
are visible. fMRI scans are performed during these mental
state attribution tasks in order to identify the brain regions
involved in this deficiency.
Our reaction to startling stimuli - termed the startle response
- is well established and has been observed in different
species for over 50 years. The stimulus is usually a loud
noise, but can be a something tactile, like a controlled
gush of air on the body. Our response to a stimulus is decreased
if a weak signal called a prepulse (shown below) is give
just before the main stimulus, and this phenomenon is called
Prepulse Inhibition (PPI). The presence of PPI is believed
to be an indication of our ability to filter and process
PPI Sequence. In Trial 1, only the pulse in given to the
study participant, who elicits a full response. In Trial
2, the pulse is preceded by the prepulse. The study participant's
response is decreased this time.
PPI is known to be disrupted in schizophrenia. In Clinical
Neuroscience Research Centre, research has focussed on how
reduced or disrupted PPI relates to cognitive functioning
and the severity of schizophrenic symptoms and whether drug
treatment affects PPI. 3 The effects of nicotine on PPI
is also an area under study in CNRC, and may account for
why 75% of people with schizophrenia smoke cigarettes.