RETRIEVAL PRACTICE Take a moment to answer each of these Learning Objective Questions (repeated here from within this section). Then click the 'show answer' button to check your answers. Research suggests that trying to answer these questions on your own will improve your long-term retention (McDaniel et al., 2009).

Symptoms of schizophrenia include disturbed perceptions, disorganized thinking and speech, and diminished, inappropriate emotions. Delusions are false beliefs; hallucinations are sensory experiences without sensory stimulation. Schizophrenia symptoms may be positive (the presence of inappropriate behaviors) or negative (the absence of appropriate behaviors).

Schizophrenia typically strikes during late adolescence, affects men slightly more than women, and seems to occur in all cultures. In chronic (or process) schizophrenia, the disorder develops gradually and recovery is doubtful. In acute (or reactive) schizophrenia, the onset is sudden, in reaction to stress, and the prospects for recovery are brighter.

People with schizophrenia have increased dopamine receptors, which may intensify brain signals, creating positive symptoms such as hallucinations and paranoia. Brain abnormalities associated with schizophrenia include enlarged, fluid-filled cerebral cavities and corresponding decreases in the cortex. Brain scans reveal abnormal activity in the frontal lobes, thalamus, and amygdala. Interacting malfunctions in multiple brain regions and their connections may produce schizophrenia’s symptoms.

Possible contributing factors include viral infections or famine conditions during the mother’s pregnancy; low weight or oxygen deprivation at birth; and maternal diabetes or older paternal age.

Twin and adoption studies indicate that the predisposition to schizophrenia is inherited. Multiple genes probably interact to produce schizophrenia. No environmental causes invariably produce schizophrenia, but environmental events (such as prenatal viruses or maternal stress) may “turn on” genes for this disorder in those who are predisposed to it.
     Possible early warning signs of later development of schizophrenia include both biological factors (a mother with severe and long-lasting schizophrenia; oxygen deprivation and low weight at birth; separation from parents; short attention span and poor muscle coordination) and psychological factors (disruptive or withdrawn behavior; emotional unpredictability; poor peer relations and solo play).