Objective: To test the hypothesis that borderline personality disorder is a manifestation of a particularly right hemispheric disturbance, involving deficient higher order inhibition, and to consider ...the therapeutic implications of the findings.
Methods: A cohort of 17 medication free borderline patients were compared with 17 age and sex matched controls by means of a study of p3a, which reflects the activity of one of the two main generators of the P300 (P3) of the event-related-potential. P3b reflects the output of the other generator. P3a, an aspect of the attentional system, depends upon prefrontally connected neurocircuitry. P3b is underpinned by a particularly parietally connected neural system. Using an oddball paradigm, P3a was extracted from the responses to targets using a novel single trial analysis.
Results: In borderline patients, over homologous electrode sites, p3a amplitudes, but not latencies, were significantly larger in the right hemisphere compared with the left. The differences were most marked fronto-centrally. No such difference was shown in the control subjects. P3a at right hemisphere sites was significantly larger in borderline compared with control patients. There was no significant difference between the groups for the left hemisphere sites.
Conclusions: The abnormally large amplitudes of P3a at right hemisphere sites in borderline patients together with the failure of habituation of P3a, are consistent with deficient inhibitory activity. Discussion of the findings suggest that they may reflect impeded maturation of the fronto-medial processing systems which, it is argued, may be a consequence of the typical early environment of those with the borderline condition. This suggestion leads to a consideration of optimal therapeutic behaviour in this condition, in particular for ‘matching’ or ‘analogical’ responsiveness.
The flow and cohesion of personal existing, the sense of self, is broken up by trauma. The survivor of repeated traumata is left with a deficiency of self involving a subtle disintegration of ...consciousness. This paper focuses on the way in which self may be fostered, building on the work of Robert Hobson. He proposed a relational means toward coherence of self. The relationship characteristic of traumatic consciousness must be transformed into the triadic relationship of "aloneness-togetherness." Steps toward this condition resemble the emergence of self in childhood. Extracts from a therapeutic session illustrate this generative pathway. After an initial state of traumatic "adualism," a conversation ensues which culminates in the emergence of self, the crucial forerunner of which is the creation of an "intimate third." The third has a unifying function.
Gamma ('40 Hz') rhythms may play a role in the integration of sensory processing activity. Impaired temporal integration may be a key feature of the associated disturbances in schizophrenia. This is ...the first study to examine the time course of Gamma activity induced in response to stimuli in this disorder.
Gamma activity induced in response to task-relevant and irrelevant auditory oddball stimuli was examined in 35 medicated schizophrenics and 35 age- and gender-matched normal controls. We employed a moving Welch window with short time FFT to examine the time course of Gamma amplitude. The amplitude spectrum for each time point was de-trended to eliminate any contribution of broad spectrum activity (EEG or EMG) to Gamma amplitude.
For targets, schizophrenics showed a significant decrease in post-stimulus Gamma response amplitude in left hemisphere and frontal sites and an increase in right hemisphere and parieto-occipital sites (P<0.0009). The abnormalities correlated with PANSS general symptom scores. In the non-targets (at a different latency), schizophrenics showed a widespread Gamma decrease (P<0.0005).
The Gamma findings in non-targets may reflect an abnormality in appropriately processing irrelevant stimuli. This could result in defective processing of the context (integration) of relevant target information.
Stress, pain, injury, and psychological trauma all induce arousal-mediated changes in brain network organization. The associated, high level of arousal may disrupt motor-sensory processing and result ...in aberrant patterns of motor function, including functional neurological symptoms. We used the auditory oddball paradigm to assess cortical arousal in children and adolescents with functional neurological symptom disorder.
Electroencephalogram (EEG) data was collected in fifty-seven children and adolescents (41 girls; 16 boys, aged 8.5-18 years) with acute functional neurological symptoms and age- sex- matched controls during a conventional auditory oddball task. The high-resolution fragmentary decomposition technique was used to analyse the amplitude of event-related potentials (ERPs) to target tones at midline sites (Fz, Cz, and Pz).
Compared to age- and sex-matched controls, and across all three midline sites, children and adolescents with functional neurological symptoms showed increased amplitude of all ERP components (P50, N100, P200, N200, and P300) (t-value range 2.28-8.20; p value-range 0.023 to < 0.001) to the emotionally-neutral auditory stimulus.
Our findings add to a growing literature indicating that a baseline state of high arousal may be a precondition for generating functional neurological symptoms, a finding that helps explain why a range of psychological and physiological stressors can trigger functional neurological symptoms in some patients. Interventions that target cortical arousal may be central to the treatment of paediatric patients with functional neurological symptom disorder.
The making of mind Meares, Russell
Australasian psychiatry,
02/2018, Volume:
26, Issue:
1
Journal Article
Peer reviewed
Open access
Objectives
The ordinary, ongoing sense of personal existing, variously called higher order consciousness, mind, or self, is disintegrated, constricted and distorted in those who have suffered ...repetitive psychological traumata. Their speech has the form of a ‘chronicle’, literal and asymbolic. This paper offers a condensed rationale for a relational approach to this, so far, neglected problem.
Conclusions:
A restorative and generative kind of relatedness is ‘natural’, the propensity for it being given to us by our biological heritage. Its first form is a game between babies and caregivers, a ‘proto-conversation’. Principles derived from this, and related developmental behaviours, guide a form of therapeutic relatedness consisting of an interactive, to-and-fro ‘patterning’ of verbal ‘pictures’, or analogues, of the subject’s immediate experience. The analogue is the first form of symbol, the use of which is the hallmark of the human.
Symptoms of borderline personality disorder (BPD) may reflect distinct breakdowns in the integration of posterior and frontal brain networks. We used a high temporal resolution measure (40-Hz gamma ...phase synchrony) of brain activity to examine the connectivity of brain function in BPD.
Unmedicated patients with BPD (n = 15) and age-and sex-matched healthy control subjects (n = 15) undertook a task requiring discrimination of salient from background tones. In response to salient stimuli, the magnitude and latency of peak gamma phase synchrony for early (0-150 ms post stimulus) and late (250-500 ms post stimulus) phases were calculated for frontal and posterior regions and for left and right hemispheres. We recorded skin conductance responses (SCRs) and reaction time (RT) simultaneously to examine the contribution of arousal and performance.
Compared with controls, patients with BPD had a significant delay in early posterior gamma synchrony and a reduction in right hemisphere late gamma synchrony in response to salient stimuli. Both SCR onset and RT were also delayed in BPD, but independently from differences in synchrony. The delay in posterior synchrony was associated with cognitive symptoms, and reduced right hemisphere synchrony was associated with impulsivity.
These findings suggest that distinct impairments in the functional connectivity of neural systems for orienting to salient input underlie core dimensions of cognitive disturbance and poor impulse control in BPD.
Widespread synchronous oscillatory activity, particularly in the gamma ('40 Hz') band, has been postulated to exist in the brain as a mechanism underlying binding. A new method of examining phase ...synchronicity across multiple electrode sites in specific EEG frequency bands as a function of time was employed, in a conventional cognitive ERP paradigm in 40 normal subjects. A significant late post-stimulus gamma synchronicity response occurred for task-relevant stimuli, whereas for task-irrelevant stimuli no such response was evident. However, an early response was seen for both task-relevant and irrelevant stimuli. This is the first empirical demonstration that widespread synchronous high frequency oscillations occur in humans in relation to cognition.
Background: Impaired processing of faces in patients with schizophrenia may underlie aspects of disturbance in their social interaction. This study examined patterns of eye fixation in subjects with ...schizophrenia and non-psychiatric controls, while processing a high resolution picture of a neutral face and a nonbiological complex geometric stimulus.
Methods: Ten-second sequences of eye movement were recorded video-oculographically (50 samples/sec) while subjects were “free-viewing” the stimuli. An essential element of the study was customized software that ensured stimulus presentation on a video display only after subjects were fixated upon a centre-screen cue, so that all subjects began stimulus processing from the same point.
Results: Compared with the control group, subjects with schizophrenia exhibited reduced scanpath lengths and a tendency toward fewer fixations for the face stimulus. They also showed an initial relative right spatial hemineglect (for the first voluntary fixation) when viewing the Rey figure, but not when viewing the face stimulus. Overall, there were no significant differences between the schizophrenia and control groups in the lateral distribution of subsequent fixations for either stimulus.
Conclusions: Disturbed spatial and temporal patterns of eye movement in some people with schizophrenia may reflect sub-optimal processing of face stimuli, that may predispose these individuals to dysfunctional interpretation of facial communication cues.
Traditional approaches to EEG modelling use the methods of classical physics to reconstruct scalp potentials in terms of explicit physical models of cortical neuron ensembles. The principal ...difficulty with such approaches is that the multiplicity of cellular processes, with an intricate array of deterministic and random influencing factors, prevents the creation of consistent biophysical parameter sets. An original, empirically testable solution has been achieved in our previous studies by a radical departure from the deterministic equations of classical physics to the probabilistic reasoning of quantum mechanics. This crucial step relocates the models of elementary bioelectric sources of EEG signals from the cellular to the molecular level where ions are considered as elementary sources of electricity. The rationale is that, despite dramatic differences in cellular machineries, statistical factors governed by the rules of the central limit theorem produce the EEG waveform as a statistical aggregate of the synchronized activity of multiple microscale sources. Based on these innovations, we introduce a method of comprehensive computerized analysis of event related potentials directly from single trial recordings. This method provides a universal model of single trial ERP components in both frequency and time domains. For the first time, this tool provides effective quantification of all significant cognitive components in single trial ERPs and represents a viable alternative to the traditional method of averaging. We demonstrate the clinical significance of the additional information provided by the new method, using ERP data from patients with borderline personality disorder and schizophrenia. Referring to the P300 as an important objective marker of psychiatric disorders, we show that the new method reliably identifies P3a and P3b as the major components of the P3. The diagnostic significance of differentiating the P3a and P3b components of P3 is that it provides an objective electrophysiological measure that distinguishes borderline personality disorder from schizophrenia.
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