Neuropsychiatric symptoms can be related to less common underlying neuropsychiatric
conditions – in this case report, the condition discussed is that of grey matter heterotopia
(GMH). The patient presented with a history of prominent aggression, impulsivity and
manipulative and attention-seeking behaviour. Episodes of depression and incidents of
deliberate self-harm and suicide attempts had been reported. Neuropsychiatric symptoms
included anxiety, a labile mood, delusional thinking and auditory hallucinations. Testing
revealed some cognitive difficulties and severe impairment of frontal lobe functions.
A magnetic resonance imaging (MRI) scan of his brain revealed the presence of GMH, which
had previously been misdiagnosed as tuberous sclerosis. An MRI scan of the brain is the
special investigation of choice for the correct diagnosis of GMH. The pathognomonic finding
is that of heterotopic grey matter abnormally located within areas of white matter. Defective
foetal neuronal migration between the third and fifth month of pregnancy can lead to GMH,
which can present later on in childhood or adolescence with epilepsy, intellectual impairment
or reading difficulties. During the late teenage years or early adulthood, a wide variety of
neuropsychiatric symptoms may be present, which can lead to diagnostic difficulties.