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Somatosensory stimulation of primary somatosensory cortex (SI) using frequency discrimination offers a direct, well-defined and accessible way of studying cortical decisions at the locus of early input processing. Animal studies have identified and classified the neuronal responses in SI but they have not yet resolved whether during prolonged stimulation the collective SI response just passively reflects the input or actively participates in the comparison and decision processes. This question was investigated using tomographic analysis of single trial magnetoencephalographic data. Four right-handed males participated in a frequency discrimination task to detect changes in the frequency of an electrical stimulus applied to the right-hand digits 2+3+4. The subjects received approximately 600 pairs of stimuli with Stim1 always at 21 Hz, while Stim2 was either 21 Hz (50%) or varied from 22 to 29 Hz in steps of 1 Hz. Both stimuli were 1 s duration, separated by a 1 s interval of no stimulation. The left-SI was the most consistently activated area and showed the first activation peak at 35-48 ms after Stim1 onset and sustained activity during both stimulus periods. During the Stim2 period, we found that the left-SI activation started to differ significantly between two groups of trials (21 versus 26-29 Hz) within the first 100 ms and this difference was sustained and enhanced thereafter (approximately 600 ms). When only correct responses from the above two groups were used, the difference was even higher at later latencies (approximately 650 ms). For one subject who had enough trials of same perception to different input frequencies, e.g. responded 21 Hz to Stim2 at 21 Hz (correct) and 26-29 Hz (error), we found the sustained difference only before 650 ms. Our results suggest that SI is involved with the analysis of an input frequency and related to perception and decision at different latencies.

HANK YOU FOR forwarding to us the letter fromPressman and colleagues (2015) and for inviting ourresponse.The role of alcohol and its impact on sleep has been stud-ied for more than a century, and a substantial knowledgebase has been created. The studies, like most scientific stud-ies, are dependent on the technology available at the timeandtheavailabilityofdata.Thisissomethingwetookintoconsiderationwhenprepar-ing our qualitative review on the impact of alcohol on nor-malsleep.Theissuesraisedcanbesummarizedasfollows:1. The use of percentages to represent the difference inthe mean values of sleep architecture variables in ourtables,2. Our results and conclusions as they pertain to the impactofalcohol onslowwavesleep(SWS),3. Ourinclusion–exclusioncriteriaforstudies,and4. Alcohol, N3, sleepwalking, and medico-legal conse-quences.1. The use of the mean value as a percentage to representsleeparchitecturevariables:1.1. In our article, we made clear how we have presentedthedata:Valuesforsleep architecturevariablesareprovidedinper-centage terms only. Where the researchers have reportedsleep stage data in minutes we have converted these intopercentages. Some variables, such as sleep onset latencyand rapid eye movement onset latency are reported inminutes only. Only the mean value is displayed for allvariables in the tables to enable a uniform approachthroughout(Ebrahimet al.,2013).1.2. This was accepted by the Journal and the peerreviewers as this review was based on highlighting 2specificareas:1.2.1. The impact of various alcohol doses and their tim-ing on nocturnal sleep in healthy controls and nor-mal populations.1.2.2. The impact of these alcohol doses on various sleepstages.1.3. Asthis was a qualitative reviewand not a quantitativemeta-analysis, it was our aim to provide a broadunderstanding to the “nonsleep specialist”readershipoftheimpactofalcoholonsleep.1.4. Furthermore, in routine clinical practice, sleepstages are reported both in actual time and as apercentage of total sleep, a simple difference in themeans between alcohol and placebo nights wasthought to be the best way to demonstrate theeffect.2. Alcohol andSWS:2.1. Alcohol andfirsthalfofnightSWS(N3):2.1.1. Low dose alcohol studies—Of the 4 studiesreported, 2 showed a significant increase in SWS(MacLean and Cairns, 1982; Van Reen et al., 2011)and the other 2 studies failed to find a significantdifference;2.1.2. Moderatedose studies—Ofthe 5 studies reported,2studies demonstrated a significant increase in SWS(Roehrs et al., 1999; Williams et al., 1983). Theother3 studiesfailedtodemonstrateany significantfindings;2.1.3. High dose studies—Five of the 9 studies reported astatistically significant increase in SWS with alco-hol (Arnedt et al., 2011; Feige et al., 2006;MacLean and Cairns, 1982; Prinz et al., 1980; Wil-liams et al., 1983) and 4 studies did not show anysignificantdifferences.The direction of evidence confirms that at low and moder-ate doses alcohol is not clearly associated with increased

The aim of the study was to identify possible disturbances of sensorimotor gating and habituation of the eye blink startle response, in patients with non-epileptic seizures (NES). Prepulse inhibition (PPI) of the startle reflex, as an operational measure of sensorimotor gating and habituation was studied in 21 patients with NES and in 22 healthy control subjects. Six NES patients were taking antiepileptic drugs at the time of testing. PPI was significantly impaired in the NES group compared to the control group, with deficits being greater in unmedicated patients. There was a trend for medicated NES patients to show higher PPI than unmedicated patients, but this was not significant. Habituation was intact in both medicated and unmedicated NES patients. It is proposed that deficits of information processing related to sensorimotor gating in patients with NES may be associated with abnormalities within the limbic system-basal ganglia circuitry which has been shown to be the substrate of 'gating' assessed by PPI. It was also found that NES patients had greater psychopathology than the control group when rated by the Traumatic Symptom Checklist (TSC-40). Overall, the anxiety subscale was the only element that was negatively correlated with PPI. It is suggested that anxiety may contribute to impairment of PPI in patients with NES.

Objective: To examine if different violent offending behaviours are associated with different clinical and neuroimaging profiles. Method: Thirty-nine schizophrenic and schizoaffective offenders from a maximum security mental hospital – 20 repetitive violent offenders (RVOs) and 19 non-repetitive violent offenders (NRVOs) – were selected for clinical and neuroimaging assessments. Results: Both groups had positive family history of mental illness and violence. Age, diagnosis, duration of illness, victim profiles and use of weapons at the time of the index offence were similar. RVOs had a higher prevalence of early parental separation, juvenile conduct problem, previous convictions of crimes not involving violence, impulsive suicide attempts, delusion of their lives being threatened at the time of the index offence and electroencephalographic (EEG) abnormalities localized to temporal lobes. NRVOs had a higher prevalence of sexual inexperience and command hallucinations to kill at the time of the index offence. Asymmetric gyral patterns at the temporo-parietal region were particularly common in RVOs and absent in NRVOs. Non-specific white matter changes in magnetic resonance imaging (MRI) and generalized cortical hypometabolism in positron emission tomography (PET) were present in both groups. Conclusions: Different structural and metabolic changes in the brain were associated with different violent offending behaviours. The complex interaction between violent behaviour, clinical features and neuroimaging findings in schizophrenia requires further studies.

A study is described which characterised the female population of Broadmoor Special Hospital on a scale (Robertson et al., 1987) which rates violence associated with the index offence and previous episodes of violence both in terms of prosecuted violence and unprosecuted incidents. This scale has been applied recently to the male population of Broadmoor (Wong et al., 1993). The findings here confirm the notion that the female population of a Special Hospital are less violent than the males in terms of rating of violence associated with the index offence and in previous convictions for violent offending. The females contain a larger proportion of patients convicted of the offence of Arson (index offence) and patients transferred from other hospitals because of being unmanageable in these settings (under Section 3 of the Mental Health Act). Extreme ratings of violence amongst the females is associated with a diagnosis of personality disorder rather than schizophrenia or psychosis.

We compare estimates of three-dimensional brain activity extracted from averaged and from selected single-trial rnagnetoencephalographic signals, in order to study activation sequences related to motor preparation, inhibition, and movement, cued on two tones (Sl and 52). We studied all possible hand-ear combinations in a right-handed subject in both initiation and inhibition, and found some marked differences between combinations. Averaging revealed activity in the right motor cortex in all combina- tions requiring movement inhibition, irrespective of laterality of finger and ear, and in the contralateral motor cortex during movement (but considerably reduced for the task with the practiced ear and finger). These activation patterns are seen in single trials with variability of latency but not position. In the average signal, a long silent period between the warning and imperative stimuli is seen; in single trials, however, recurring sequences of activation linking frontal and posterior areas are seen throughout the analysis period in all combinations. These results show that single-trial analysis is needed to understand all the significant neural correlates of this task.

Elderly offenders aged 60 and above constitute less than 8% of the population in a maximum security mental hospital, These offenders fall into 2 groups: 1) first admission at or after the age of 50 and 2) first admission before 50, Fewer first time offenders committed homicide in the first group than those in the second group, Neuropsychiatric disturbance and sex offending was common among male first time offenders in the first group; in contrast, schizophrenia and violent offending against persons was found more often in the second group, It is argued that elderly first time offenders should be given adequate neuropsychiatric assessment.

A retrospective study of brain investigations of 372 male patients in a maximum-security mental hospital patients is described. All computed tomography (CT) scan and electroencephalography (EEG) reports were collected and rated blind; patients were subsequently divided into 3 groups according to the violence rating of their pre-admission offending behaviour. The 3 groups were similar in their mean age, psychiatric diagnosis, Wechsler Adult Intelligence Scale score and proportions of patients investigated with EEG and CT. In the most violent group, 20% had focal temporal electrical abnormalities on EEG (slowing and/or sharp waves) and 41% had structural abnormalities localised to temporal lobe on CT (dilated temporal horn and/or reduced size of temporal lobe). The corresponding figures for the least violent group are 2.4% and 6.7% respectively. These results suggest that high violence rating scores are associated with temporal lobe abnormalities on CT and abnormal temporal electrical discharges on EEG.

The male population of a high security hospital is described in terms of the profile of patients' pre-admission violence (index offence and previous convictions), using a rating scale described by Robertson et al. (1987). The ratings show that Broadmoor Hospital patients exhibit a high level of violence both in terms of previous convictions and related to their index offence. Only one patient was admitted after a non-violent index offence. At Broadmoor 55 per cent of the population had previous convictions of violence before the index offence; 17 per cent had a previous history of unprosecuted violence before the present admission; 19 per cent were admitted to the hospital following a single severely violent index offence which resulted in the death or serious injury of the victim; 72 per cent of this last group have the clinical diagnosis of schizophrenia. In this study, the rating scale was noted as a useful screening instrument that can describe the violence profile of Special Hospital patient...

International audience; ABSTRACT : BACKGROUND : Saccadic eye movements align the two eyes precisely to foveate a target. Trial-by-trial variance of eye movement is always observed within an identical experimental condition. This has often been treated as experimental error without addressing its significance. The present study examined statistical linkages between the two eyes' movements, namely interocular yoking, for the variance of eye position and velocity. METHODS : Horizontal saccadic movements were recorded from twelve right-eye-dominant subjects while they decided on saccade direction in Go-Only sessions and on both saccade execution and direction in Go/NoGo sessions. We used infrared corneal reflection to record simultaneously and independently the movement of each eye. Quantitative measures of yoking were provided by mutual information analysis of eye position or velocity, which is sensitive to both linear and non-linear relationships between the eyes' movements. Our mutual information analysis relied on the variance of the eyes movements in each experimental condition. The range of movements for each eye varies for different conditions so yoking was further studied by comparing GO-Only vs. Go/NoGo sessions, leftward vs. rightward saccades. RESULTS : Mutual information analysis showed that velocity yoking preceded positional yoking. Cognitive load increased trial variances of velocity with no increase in velocity yoking, suggesting that cognitive load may alter neural processes in areas to which oculomotor control is not tightly linked. The comparison between experimental conditions showed that interocular linkage in velocity variance of the right eye lagged that of the left eye during saccades. CONCLUSIONS : We conclude quantitative measure of interocular yoking based on trial-to-trial variance within a condition, as well as variance between conditions, provides a powerful tool for studying the binocular movement mechanism.

Objective: To investigate the accurate localisation of weak, transient, neural sources under conditions of varying difficulty. Methods: Multiple dipolar sources placed within a head-shaped phantom at superficial and deep locations were driven separately or simultaneously by a short-lasting current with varied amplitudes. Artificial MEG signals that were very similar to the human High Frequency Oscillations (HFO) were produced. MEG signals of HFO were also recorded from median nerve stimulation. Different inverse techniques were used to localise the phantom dipoles and the human HFO generators. Results: The human HFO were measured around 200 and 600 Hz by using only 120 trials. The 200 Hz HFO were localised to BA3b. The superficial phantom’s source was localised with an accuracy of 2–3 mm by all inverse techniques (120 trials). The ‘subcortical’ source was localised with an error of �5 mm. Localisation of deeper ‘thalamic’ sources required more trials. Conclusion: MEG can detect and localise weak transient activations and the human HFO with an accuracy of a few mm at cortical and subcortical regions even when a small number of trials are used. Significance: Localizing HFO to specific anatomical structures has high clinical utility, for example in epilepsy, where discrete HFO appears to be generated just before focal epileptic activity.

Crimes carried out during or arising from sleep highlight many difficulties with our current law and forensic sleep medicine clinical practice. There is a need for clarity in the law and agreement between experts on a standardised form of assessment and diagnosis in these challenging cases. We suggest that the time has come for a standardised, internationally recognised diagnostic protocol to be set as a minimum standard in all cases of suspected sleep-related forensic cases. The protocol of a full medical history, sleep history, psychiatric history, neuropsychiatric and psychometric examination and electroencephalography (EEG), should be routine. It should now be mandatory to carry out routine polysomnography (PSG) to establish the presence of precipitating and modulating factors. Sleepwalking is classified as insane automatism in England and Wales and sudden arousal from sleep in a non-sleepwalker as sane automatism. The recent case in England of R v. Lowe (2005) highlights these anomalies. Moreover, the word insanity stigmatises sleepwalkers and should be dropped. The simplest solution to these problems would be for the law to be changed so that there is only one category of defence for all sleep-related offences – not guilty by reason of sleep disorder. This was rejected by the House of Lords for cases of automatism due to epilepsy, and is likely to be rejected for sleepwalkers. Removing the categories of automatism (sane or insane) would be the best solution. Risk assessment is already standard practice in the UK and follow up, subsequent to disposal, by approved specialists should become part of the sentencing process. This will provide support for the defendant and protection of the public.

All sleep stages contain epochs with high-amplitude electrophysiological phasic events, alternating with quieter "core periods." High-amplitude and core state properties cannot be disentangled with PET and fMRI. Here from high temporal resolution magnetoencephalography data, regional changes in neuronal activity were extracted during core periods in different frequency bands for each sleep stage and waking. We found that gamma-band activity increases in precuneus during light sleep (stages 1/2) and in the left dorso-medial prefrontal cortex (L-DMPFC) during deep sleep (stages 3/4). The L-DMPFC activated area expands laterally during rapid eye movement (REM) sleep, into a volume of about 5 cm(3) bounded by regions attributed to Theory of Mind (ToM) and default systems, both involved in introspection. Gamma band activity in this area was higher during REM sleep than other sleep stages and active wakefulness. There is a tantalizing correspondence between increased wide-band activity (dominated by low frequencies) in early non-REM (NREM) sleep stages and increases in gamma-band activity in late NREM and REM periods that we attribute to a lateral disinhibition mechanism. The results provide a description of regional electrophysiological changes in awake state, light and deep sleep, and REM sleep. These changes are most pronounced in the L-DMPFC and the other areas around the dorsal midline that are close to, but do not overlap with areas of the default and ToM systems, suggesting that the DMPFC, particularly in the left hemisphere, plays an important role in late NREM stages, in REM and possibly in dreaming.

Out-of-body experiences, in which the person feels they are viewing the world from outside their body, may be spontaneous or triggered by pain or fear, due to failure to integrate proprioceptive, tactile and visual information in the right parieto-temporal junction. They are similar to autoscopy, namely seeing your body in extra-personal space. But out-of-body experiences can occur in a near-death state during a cardiac arrest and be remembered even though brain processes are distorted or absent. Reliable accounts of patients who have acquired verifiable information while clinically dead suggest that consciousness may not after all be limited to the brain.

With sufficiently fast data sampling, ubiquitous sharp transients appear in magnetoencephalography (MEG) data. Initially, no known collective neuronal activity could explain MEG signal generation well above 100 Hz, so it was assumed that these transients were entirely composed of background electronic noise that could be eliminated by filtering and averaging. Recent studies at the cellular level provided evidence for synchronous synaptic input to dendrites and volleys of near-simultaneous action potentials. MEG studies have also identified high-frequency oscillations well above 200 Hz after averaging large number of somatosensory evoked responses. In this study, we searched for evidence of high-frequency neuronal activity in the raw MEG signal using the highest sampling rate available with our hardware. Two human subjects participated in three experiments using visual cues to define planning, preparation, and execution or inhibition of saccades. Tomographic analysis identified “MEG spikes” that were widely distributed across the cortex, cerebellum, and brainstem during cue presentations and saccades. Here we demonstrate how these MEG spikes can be recorded and localized in real time and show that task demands influence their properties. The MEG spikes were organized into feedforward and corollary discharge sequences that could, when combined with the slower activity-linked processing in discrete brain areas over long periods, lasting hundreds of milliseconds. Preparation for impending saccade began as soon as relevant information became available. Cues providing partial information initiated competing motor programs for as yet undecided future actions that were maintained until cues with new information resolved the uncertainty.

The cerebellum has traditionally been associated with motor movements but recent studies suggest its involvement with fine timing, sensory analysis and cognition. Much of the new data comes from neuroimaging techniques such as fMRI and PET, which have high spatial resolution and show that for even simple stimuli many cerebellar and cortical areas are involved. We use examples from recent studies to demonstrate that magnetic field tomography (MFT) offers a new and powerful tool for studying cerebellar function through real time localization of cortical, brainstem and cerebellar activations over timescales ranging from a fraction of a millisecond to seconds, minutes and hours. The examples include demonstration of cerebellar activations along well-established anatomical pathways during saccades and the visualization of the ascending medullar volley after median nerve stimulation. MFT analysis of single trial MEG signals elicited by the presentation of faces in emotion and object recognition tasks, show changes in cerebellar activation between schizophrenics and normal subjects in agreement with proposals for disturbed cerebellar function in schizophrenia. The ability of MFT to identify cerebellar, brainstem and cortical activations in real time can add new insights about dynamics of brain activity to the recent findings about cerebellar function from PET and fMRI.

The cerebellum has traditionally been associated with motor movements but recent studies suggest its involvement with fine timing, sensory analysis and cognition. Much of the new data comes from neuroimaging techniques such as fMRI and PET, which have high spatial resolution and show that for even simple stimuli many cerebellar and cortical areas are involved. We use examples from recent studies to demonstrate that magnetic field tomograhy (MFT) offers a new and powerful tool for studying cerebellar function through real time localization of cortical, brainstem and cerebellar activations over timescales ranging from a fraction of a millisecond to seconds, minutes and hours. The examples include demonstration of cerebellar activations along well-established anatomical pathways during saccades and the visualization of the ascending medullar volley after median nerve stimulation. MFT analysis of single trial MEG signals elicited by the presentation of faces in emotion and object recognition tasks, show changes in cerebellar activation between schhizophrenics and normal subjects in agreement with proposals for disturbed cerebellar function in schizophrenia. The ability of MFT to identify cerebellar, brainstem and cortical activations in real time can add new insights about dynamics of brain activity to the recent findings about cerebellar function from PET and fMRI.

We trained humans to detect changes in the frequency of 21 Hz electrical stimulation applied to the right-hand digits 2+3+4 and recorded the MEG signal before, during and after the training. We evaluated changes for each digit and observed: (1) activations in the left primary somatosensory (L-SI) and medial parietal precuneus (PCu) areas; (2) after the training in L-SI, the 21 Hz spectral power increased for digits 3 and 4 over the stimulation period, while the 10 Hz spectral power increased for digit 3 only around the stimulus onset and offset; (3) only digit 3 showed significant change in the correlation between the two areas around the stimulus onset and offset, at the same latency ranges of increased 10 Hz spectral power. During the training, we found that the L-SI activation reflects the input frequencies of stimuli at early latencies but correlates with the subject's perception between low and high frequencies at later latencies.

Attentional effects in the striate and extrastriate cortex have been the subject of intense research interest in many recent studies using single unit recordings in animals and neuroimaging methods in humans. The consensus emerging from these studies places attentional effects first in extrastriate areas. Attentional influence in this view is reaching V1 rather late, some 150 ms after stimulus onset, well after the main N1/P1 complex which peaks about 50 ms earlier. We show here that an earlier wave of attentional effects is present in V1 beginning soon after 50 ms and reaching a peak between 90 and 100 ms after stimulus onset. This effect is identified in a comparison of passive viewing of stimuli and an active GO/NOGO task using the same stimuli. The effect was best seen in the tomographic analysis of single trial magnetoencephalographic (MEG) data, designed to cope with simultaneous activations throughout the brain at each timeslice. This early attentional modulation might still be interpreted as a modulation of the striate cortex from extrastriate areas because attention related changes are present in the prestimulus period in both dorsal and ventral extrastriate areas.

Old ideas about attention and consciousness seemed to be irrelevant today. We re-evaluated them here in the light of recent neuroimaging data, data from pathological conditions where attentional mechanisms are impaired and the knowledge that activity following a stimulus spreads rapidly very widely. We present the case that the multiple systems both cortical and subcortical involved in attentional processes can best be studied using tomographic, millisecond by millisecond single trial analysis of magnetoencephalographic data.

Contingent negative variation and evoked potentials to visual erotic stimuli were recorded from 8 brain sites in a sample of 62 right-handed men aged 20-50, half of whom declared paraphilic interests and half claimed "normal" heterosexual interests. To quantify erotic preferences, a "variance quotient" (VQ) was calculated from scores on the Wilson Sex Fantasy Questionnaire using the formula VQ = Impersonal + Sadomasochistic fantasies/Intimate + Exploratory fantasies. Stimuli consisted of 57 paraphilic slides (depicting fetishistic and sadomasochistic themes), 57 heterosexual erotic slides (explicit pictures of nude women, coitus, and oral sex), and 57 neutral slides (landscapes and street scenes). The P600 response appeared to be the best indicator of erotic preferences, butthe locus of maximum arousal was different for paraphilic and heterosexual stimuli. The primary brain site for heterosexual arousal was P4 (right parietal), where there was a -.34 (p.01) correlation between VQ and P600 (i.e., nonvariant males showed greater responses to normal erotic stimuli at this location). For paraphilic stimuli, there was a correlation of .26 (p.05) between the VQ and P600 response at the F3 (left frontal) site (i.e., paraphilic men showed greater responses to paraphilic stimuli than normal men at this brain location). Dividing the sample into groups of 23 paraphilics and 23 heterosexual controls on the basis of their VQs showed that "normals" differentiated between stimulus types more at the P4 than paraphilics. Theoretical and clinical implications of these findings are discussed.

The FDG PET brain scans from 31 offenders with schizophrenia and schizoaffecive disorder from a maximum security mental hospital were compared with those of normal controls (N = 6) in terms of relative FDG uptake in a range of regions covering frontal and temporal regions. The patient sample was divided into those who had a history of repetitive violent offending (RVO, N = 17) and those without a repetitive violent history (NRVO, N = 14) according to the violence rating of their pre-admission convictions. Reduced FDG uptake was noted at both the right and left anterior inferior temporal (R and L AIT) regions in NRVOs but only at LAIT in RVOs. NRVOs had significantly lower FDG uptake at RAIT than RVOs. The findings suggest that metabolic changes at AIT may be related to different patterns of violent offending in patients with schizophrenia.

BackgroundConcurrent use of lithium and ECT is suspected to increase neurotoxicity.MethodA retrospective case-control study over an eight-year period was conducted to investigate the adverse effects of a combined lithium/ECT treatment Thirty-one subjects with combined lithium/ECT treatment were compared with a control group (ECT only) of 135 cases matched for age and sex.ResultsMost cases in both groups had no adverse effects. Three (10%) study group subjects and 15 (11 %) controls experienced brief delirium. Three controls and none of the subjects developed a prolonged confusion. There were no significant differences in the profile of other adverse effects between the two groups.ConclusionPrescription of lithium together with ECT was not associated with higher frequency of adverse effects.

Sir, We read with interest the review article in Brain by Siclari et al . (2010). Although the authors cite some relevant studies, in our opinion, they do not adequately discuss the possible causal link between alcohol ingestion and disorders of arousal. Siclari and colleagues state ‘criteria for establishing the putative role of an underlying sleep disorder in a specific violent act have been proposed by Mahowald and coworkers (1990)’; and the authors partially reproduce, as Table 4 at page 3505, material from that earlier publication including the statement: ‘Alcohol or drug intoxication precludes the use of disorder of arousal in forensic cases’. Our reading of the cited paper from 1990, involving several of the same authors, is subtly different: ‘To assist in the determination of the putative role of an underlying sleep disorder in a specific …

A case is reported of a patient who had a respiratory arrest on a high dependency ward in a High Security Hospital with an unusual presentation. The patient had head and upper abdominal petechial haemorrhages with extensive conjunctival haemorrhaging. A considered antecedent for this potentially life-threatening presentation was strangulation. Analysis of all the available clinical information supports the hypothesis that he had a single tonic-clonic seizure with a focal-motor onset. This constitutes an unusual consequence of a partial seizure with secondary generalization.

The advent of new imaging techniques is broadening our understanding of the major psychiatric illnesses. The increased knowledge of brain function will have consequences for the expert medical witness who has to give evidence in court. Both the insanity defence and the defence of automatism depend on disorders of the mind. Psychiatry is now able in many cases to produce evidence that these are consequent upon disorders of the brain. In presenting evidence in court there is an apparent conflict between ‘brain words' and ‘mind words'.

Broadmoor Hospital is one of three Special Hospitals provided for the treatment of patients of ‘dangerous or violent propensities', under conditions of security. By definition, it caters for a unique and highly selected group of patients; patients who it is thought are too dangerous to be cared for in more conventional psychiatric facilities. Studies of such selected groups of patients may help us towards a better understanding of the relationship between dangerous behaviour and mental illness. Special groups of patients have been studied (Blackburn, 1970; Le Couteur, 1966; McGrath, 1958), but apart from a general paper by Gould (1957), and a recent research report by Black (1973) remarkably little is known either about the characteristics of those patients who go into hospitals, or about what happens to them after they leave the hospitals.

SummaryUsing a classical click/flash paradigm the contingent negative variation (CNV) was recorded from 60 consecutive male admissions to Broadmoor Hospital. Clinical and psychometric Minnesota Multiphasic Personality Inventory (MMPI) assessments were made independently of the electroencephalography (EEG) data. A trend for higher amplitude CNV's to be recorded from patients with a clinical diagnosis of antisocial (psychopathic) personality was observed. Patients with a Mental Health Act diagnosis of psychopathic disorder had significantly higher voltage CNV's than those in the mental illness category. These CNV differences were only found in the primary (non-anxious, sociable) psychopaths. Secondary (neurotic, unsociable) psychopaths did not differ from staff controls. A positive association between CNV voltage and the personality factor of sociability(sociable-shy dimension) was observed. A weak, negative correlation between CNV amplitude and impulsivity (impulsive-controlled dimension) was also apparent. All subjects showed an habituation effect across trials. No difference in response variability between successive series of trials was apparent in any of the patient groups.

A retrospective case-note survey was carried out on 31 subjects admitted with temporal-lobe epilepsy to the Maudsley hospital from 1974–1983 inclusive. Fourteen aggressive subjects were compared with the non-aggressive patients on 95 organic, developmental, and social variables. Aggressive behaviour was associated with male sex, early onset of seizures, and a history of long-standing behavioural problems. Aggressive subjects had lower mean IQ scores and poorer occupational records than controls. No relationship was found between aggression and the presence of specific EEG or CAT scan findings, or a history of psychosis. The results demonstrate the complex interplay between organic and socially mediated factors underlying aggressive behaviour in temporal-lobe epilepsy.

Scientific study of sleep has shown that sleepwalking and night terrors occur in stage 4 sleep. Both run in families, and are precipitated by various specific trigger factors. Behavior can be complex and purposeful and frequently may lead the sleeper into danger. Murder and assault while asleep do rarely occur, and the aggressive acts can appear purposeful, directed, and coordinated. Sleepwalking in the United Kingdom is considered a sane automatism and a successful plea of not guilty leads to an acquittal. Therefore, sleepwalking should only be accepted as a defense by forensic psychiatrists after establishing beyond reasonable doubt that the characteristics of a sleepwalking episode are present. The law on automatism in England is muddled and requires revision.

Minor episodes of aggressive behavior are relatively common in some populations of patients with epilepsy. However, they are probably no more common than in populations who are socially disadvantaged or who have brain damage. The confusion that commonly follows seizures can lead to apparently aggressive behavior. Rarely, the seizure itself may lead to directed aggression; very rarely does it lead to murderous attacks. Although post-ictal psychotic aggression is usually not severe, when it is driven by prominent delusions and hallucinations, it can result in self-destructive acts or serious violence. Clearly, however, it is quite unfair to globally classify epileptics as aggressive, and the time has come to abandon this stereotype.

Howard et al. (1982) reported an association in mentally abnormal offenders between psychometric impulsiveness and the degree of differentiation in the contingent negative variation (CNV) recorded at the vertex between Go and No Go conditions in a Go/No Go signalled avoidance task. The present study aimed to investigate whether this finding extended to two samples of young, healthy volunteers using a variety of impulsiveness-related measures. As well as examining the Go/No Go CNV recorded from the vertex, the present study investigated the Go/No Go CNV recorded bilaterally at central (C3 and C4: Experiment 1) and temporal (T3 and T4: Experiment 2) electrode derivations. The study also investigated relationships between the Go/No Go CNV and subjective state. including stress and arousal as measured by a mood-adjective checklist, as well as several task-related state measures. The Go CNV recorded at the vertex was found to relate to a variety of impulsiveness-related measures, in particular to Eysenck's Impulsivity, Venturesomeness and Psychoticism. The Go/No Go CNV recorded at temporal sites was more closely related to measures of Emotionality. While the Go CNV appears to be an electrocortical index of a neuropsychological system mediating subjective stress, the No Go CNV appears to index subjective arousal. Results are interpreted in terms of orthogonal 'primary' and 'secondary' appraisal processes (Folkman et al., 1979), and their implications for Gray's (1982) neuropsychological theory of anxiety and Tucker and Williamson's (1984) neural control systems model of human self-regulation are outlined.