Neurological abnormalities and cognitive ability in first-episode psychosis.
BACKGROUND
It remains unclear if the excess of neurological soft signs, or of certain types of neurological soft signs, is common to all psychoses, and whether this excess is simply an epiphenomenon of the lower general cognitive ability present in psychosis.


OBJECTIVE
To investigate whether an excess of neurological soft signs is independent of diagnosis (schizophrenia v. affective psychosis) and cognitive ability (IQ).


METHODS
Evaluation of types of neurological soft signs in a prospective cohort of all individuals presenting with psychoses over 2 years (n=310), and in a control group from the general population (n=239).


RESULTS
Primary (P<0.001), motor coordination (P<0.001), and motor sequencing (P<0.001) sign scores were significantly higher in people with any psychosis than in the control group. However, only primary and motor coordination scores remained higher when individuals with psychosis and controls were matched for premorbid and current IQ.


CONCLUSIONS
Higher rates of primary and motor coordination signs are not associated with lower cognitive ability, and are specific to the presence of psychosis.
Dazzan
Paola
P
Department of Psychiatry, Box 63, Institute of Psychiatry, De Crespigny Park, London SE5 8AF, UK. p.dazzan@iop.kcl.ac.uk
Lloyd
Tuhina
T
Morgan
Kevin D
KD
Zanelli
Jolanta
J
Morgan
Craig
C
Orr
Ken
K
Hutchinson
Gerard
G
Fearon
Paul
P
Allin
Matthew
M
Rifkin
Larry
L
McGuire
Philip K
PK
Doody
Gillian A
GA
Holloway
John
J
Leff
Julian
J
Harrison
Glynn
G
Jones
Peter B
PB
Murray
Robin M
RM