True: Simultanagnosia or visual disorientation is the inability to attend to more than a very limited sector of the visual field at any given moment, the rest being in a sort of fog or out of focus. It is detected by asking the subject to describe a complex design (Lishman 1997, p. 61; Yudofsky & Hales 2002, pp. 85, 174).

True: There is a familial form of CJD seen in Libyan and Tunisian Jews which gives them 100 ? the risk of the general population. Before the mutation was found, the high incidence of CJD was attributed to eating sheep’s eyes. A very high incidence of CJD has been described in Libyan Jewish immigrants to Israel (Lishman 1997, p. 475).

True: The neuropathological characteristics of CJD are neuronal loss, spongiform vacuolation and reactive astrogliosis. There are no neurofibrillary tangles, senile plaques, circumscribed atrophy or inflammatory reaction. However, extracellular amyloid plaques are present in 10% of cases, especially in the cerebellum. In contrast, the essential diagnostic pathological feature of nvCJD is the presence of multiple, florid, large, fibrillary amyloid plaques in the cerebral and cerebellar cortices, especially in the occipital cortex (Lishman 1997, p. 478; Sadock & Sadock 2005, p. 471; Wright et al 2005, p. 387).

True: A number of family and twin studies have demonstrated high heritability of EEG alpha power (80%) and alpha peak frequency (80%), P300 amplitude (60%) and P300 latency (50%).

True: The amygdala is involved in emotion recognition and fear conditioning. The projections of the central nucleus of the amygdala to the locus coeruleus and hypothalamus mediate the arousal and autonomic responses associated with fear and anxiety. Thus, the amygdala plays a key role in the integration of the behavioural and neuroendocrine components of the stress response as well as anxiety symptoms associated with complex partial seizures. MRI studies show smaller amygdala volumes in patients with complex partial seizures who have ictal fear than those who do not (Mitchell 2004, p. 438; Trimble & Schmitz 2002, p. 32).

False: A normal inter-ictal EEG does not rule out the possibility of seizure disorders. However, a normal EEG during a seizure would (Mitchell 2004, p. 116; Yudofsky & Hales 2002, p. 678).

True: Non-epileptic seizures are notoriously difficult to distinguish from epileptic seizures. During and immediately after generalized tonic-clonic seizures there are usually up-going plantars and wide-fixed pupils. This is not seen in non-epileptic seizures (Lishman 1997, p. 292).

False: The prefrontal cortex projects to subcortical structures in a series of distinct closed loops. Disruption of any of these produces a pattern of discrete deficits. However, these clinical syndromes seldom present as neatly in clinical practice as pathological lesions seldom respect anatomy. The syndromes are:

The mnemonic ‘Don’t Let Exam Demons Marr Any Opportunity For Passing’ can be used to help remember this. The initial letters spell DLEDMAOFP. DorsoLateral – Executive function. DorsoMedial – Akinetic mutism (also apathy and attention). Orbito-Frontal – Personality change.

Though clinical lesions seldom fall neatly into these categories it is the dorsomedial syndrome which is most closely associated with akinetic mutism (Lindsay & Bone 2004, p. 109; Mitchell 2004, pp. 57, 77; Sadock & Sadock 2005, p. 325).

False: The proteasome is an intracellular structure involved in the degradation of misfolded proteins. The proteome is the total number of proteins produced by a genome (Alberts et al 2000, p. 358).

False: Post-traumatic amnesia (PTA) is a more valid and useful guide to the severity of head injury and subsequent prognosis than retrograde amnesia, the duration of unconsciousness or overt confusion. PTA is highly variable from case to case and serves as an index of severity. It is a permanent index of severity and is available to the clinician who enquires long after the injury. PTA in closed head injuries is also an indicator of the time lapse before the patient returns to work (Lishman 1997, p. 171; Mitchell 2004, p. 128).

True: The ‘Trojan horse theory’ postulates that the HI virus enters the brain through infected macrophages and microglia (Lishman 1997, p. 322).

False: The cumulative lifetime prevalence of HIV dementia in infected adults is about 15%. Highly active antiretroviral therapy (HAART) reduces the incidence by about 50%. HIV-associated dementia is usually seen in the late stages of HIV illness, CD4 cell count nadir less than 200 per ?L, higher HIV RNA viral load, lower educational level, older age, anaemia, illicit drug use and female gender (Lishman 1997, p. 324; Mitchell 2004, p. 186; Sadock & Sadock 2005, p. 433).

False: The EEG in Huntington’s disease shows loss of alpha rhythm. There may be generalized low voltage fast activity or random slow activity. As the disease progresses the amplitude decreases and the EEG may become completely flat. These changes are not ubiquitous. Normal traces may be seen even in advanced disease (Lishman 1997, p. 470; Yudofsky & Hales 2002, p. 964).

True: The dentate gyrus is part of the hippocampal formation along with the hippocampus and subiculum. Broca in 1878 coined the term ‘limbic’ for the limbus or rim of cortex adjacent to the corpus callosum and diencephalon. The term limbic system is most often used to describe the areas of the brain involved in emotion, memory or aggression, e.g. the hippocampal formation, septal region, parahippocampal gyrus, cingulate gyrus, insula and amygdala (Fitzgerald 1996, p. 267; Yudofsky & Hales 2002, p. 279).

False: In diencephalic lesions, e.g. in Korsakoff’s syndrome, patients are usually unaware of their illness and may deny they have any impairment (Lishman 1997, pp. 19, 69).

False: The lifetime prevalence of major depression in multiple sclerosis is 25–50%, i.e. three times the general population rate. Physical disability and fatigue are indirectly associated with depression via their effects on day-to-day functioning (Feinstein 1999, p. 29; Mitchell 2004, p. 143).

True: Two facial pain syndromes may respond to antidepressants. In temporomandibular joint dysfunction (Costen’s syndrome, facial arthralgia) there is a dull ache around the joint. In contrast, atypical facial pain is a deeper aching or throbbing pain (Gelder et al 2006, p. 212).

True: Psychosis, particularly affective psychosis, occurs in Parkinson’s disease. In most cases medications and overmedication can be implicated. Non-drug related cases are usually transient and often associated with dementia. Schizophrenia-like psychosis is rare (Lishman 1997, p. 657; Mitchell 2004, p. 152).

False: Unlike many porphyrias, acute intermittent porphyria is not associated with skin rashes. Symptoms of acute intermittent porphyria are caused when intermediates of haem synthesis accumulate in abnormal and toxic amounts. Symptoms include abdominal pain, vomiting, constipation, muscle weakness, hypertension, tachycardia, peripheral neuropathy and mental state changes (Lishman 1997, p. 116).

False: The electrodermal system is under the sole control of the sympathetic nervous system rather than a dynamic balance between sympathetic and parasympathetic. Sympathetic activation may be tonic or phasic. Anxiety increases tonic sympathetic activity and sweating and hence increases conductance. Depression may decrease skin conductance. Relaxation decreases skin conductance (Sadock & Sadock 2005, p. 1729).

True: NREM sleep predominates at all times in the night though REM gets proportionately greater. In successive sleep cycles the amount of NREM sleep decreases and the amount of REM sleep increases. REM accounts for 25% of the total sleep time. Most REM periods occur during the last third of the night, as opposed to stage 4 sleep, where most occurs in the first third of the night (Gelder et al 2000, p. 996).

True: Sleepwalking may be precipitated by traumatic events such as parental death or divorce, change of school or birth of a sibling. There may be a disturbed family background or a difficult relationship with the parents. The majority have a history of acting out behaviours, delinquency and theft. Many show evidence of anxiety, depression and depersonalization. The majority of adult sleepwalkers have no psychiatric disorders (Lishman 1997, p. 736).

True: Neurofibrillary tangles are largely composed of phosphorylated tau protein (Lishman 1997, p. 441).

False: However, hyperparathyroidism does. Hyperparathyroidism may present with malaise, depression, renal calculi, peptic ulcers and corneal calcification. Hyperparathyroidism leads to absorption of bone which when advanced may lead to cysts or destructive ‘brown tumours’.

True: Writer’s cramp, torticollis, and blepharospasm with jaw and mouth movements (Meige syndrome) are focal dystonias (Yudofsky & Hales 2002, p. 164).