Craig J. Gonsalvez

Face to face: visual scanpath evidence for abnormal processing of facial expressions in social phobia

Cognitive models of social phobia propose that cognitive biases and fears regarding negative evaluation by others result in preferential attention to interpersonal sources of threat. These fears may account for the hypervigilance and avoidance of eye contact commonly reported by clinicians. This study provides the first objective examination of threat-related processing in social phobia. It was predicted that hyperscanning (hypervigilance) and eye avoidance would be most apparent in social phobia for overt expressions of threat. An infrared corneal reflection technique was used to record visual scanpaths in response to angry, sad, and happy vs. neutral facial expressions. Twenty-two subjects with social phobia were compared with age- and sex-matched normal controls. As predicted, social phobia subjects displayed hyperscanning, (increased scanpath length) and avoidance (reduced foveal fixations) of the eyes, particularly evident for angry faces. The results could not be explained by either medication or co-morbid depression. These findings are consistent with theories emphasising the role of information processing biases in social phobia, and show promise in the application to treatment evaluation in this disorder.

Social phobics do not see eye to eye:: A visual scanpath study of emotional expression processing

Clinical observation suggests that social phobia is characterised by eye avoidance in social interaction, reflecting an exaggerated social sensitivity. These reports are consistent with cognitive models of social phobia that emphasize the role of interpersonal processing biases. Yet, these observations have not been verified empirically, nor has the psychophysiological basis of eye avoidance been examined. This is the first study to use an objective psychophysiological marker of visual attention (the visual scanpath) to examine directly how social phobia subjects process interpersonal (facial expression) stimuli. An infra-red corneal reflection technique was used to record visual scanpaths in response to neutral, happy and sad face stimuli in 15 subjects with social phobia, and 15 age and sex-matched normal controls. The social phobia subjects showed an avoidance of facial features, particularly the eyes, but extensive scanning of non-features, compared with the controls. These findings suggest that attentional strategies for the active avoidance of salient facial features are an important marker of interpersonal cues in social phobia. Visual scanpath evidence may, therefore, have important implications for clinical intervention.

P300 amplitude is determined by target-to-target interval

P300 event-related brain potential (ERP) measures are affected by target stimulus probability, the number of nontargets preceding the target in the stimulus sequence structure, and interstimulus interval (ISI). Each of these factors contributes to the target-to-target interval (TTI), which also has been found to affect P300. The present study employed a variant of the oddball paradigm and manipulated the number of preceding nontarget stimuli (0, 1, 2, 3) and ISI (1, 2, 4 s) in order to systematically assess TTI effects on P300 values from auditory and visual stimuli. Number of preceding nontargets generally produced stronger effects than ISI in a manner suggesting that TTI determined P300 measures: Amplitude increased as TTI increased for both auditory and visual stimulus conditions, whereas latency tended to decrease with increased TTI. The finding that TTI is a critical determinant of P300 responsivity is discussed within a resource allocation theoretical framework.

Response inhibition deficits in obsessive–compulsive disorder

Difficulty inhibiting irrelevant information may play a central role in the aetiology of obsessive-compulsive disorder (OCD). The aim of the present study was to determine whether OCD subjects (n=20) exhibit deficits in behavioural and cognitive inhibition compared with a clinical control group diagnosed with panic disorder (n=20). All subjects were administered a Go/Nogo task (a measure of behavioural inhibition) and a Stroop test (a measure of cognitive inhibition). OCD subjects made more commission errors on the Go/Nogo task, and they made more errors and displayed longer reaction times on the interference trial of the Stroop task. Trends towards correlations were observed between OCD severity scores and Stroop reaction time, where the more severe the OCD symptoms the faster was the response. No correlations between clinical symptomatology or subject demographics and the Go/Nogo task were observed. It was demonstrated that OCD subjects exhibit deficits in behavioural and cognitive inhibition, which together may underlie the repetitive symptomatic behaviours of the disorder, such as compulsions and obsessions.

Executive functions in obsessive–compulsive disorder: state or trait deficits?

OBJECTIVE Despite the neuropsychology literature providing reliable evidence of impaired executive functions in obsessive-compulsive disorder (OCD), to date it has not been determined whether these deficits are trait-related (independent of symptomatology) or state-dependent (dependent on symptomatology). The current research examines the executive functions in OCD in a comprehensive manner and, for the first time, assesses the stability of these deficits over the developmental course of the disorder. METHOD Using a cross-sectional design, Study 1 examined the executive functions (set shifting, inhibition, planning, verbal fluency and working memory) in 60 subjects (20 actively Symptomatic OCD, 20 Remitted OCD and 20 Panic Disorder). Using a longitudinal design, Study 2 reassessed a subsample of OCD subjects (participants in Study 1) once they reached remitted status. RESULTS Study 1 found that the OCD groups exhibited deficits in set shifting and inhibition relative to Panic Disorder controls; however, no deficits were observed in planning, verbal fluency or working memory. There were no differences found between the Symptomatic and Remitted OCD groups on any of the executive function measures. Study 2 found that the identified executive function deficits in individuals were stable over time and remained unchanged despite symptom remittance. CONCLUSION Current results confirm the presence of specific executive function deficits in OCD, and indicate that these deficits are trait-like in nature.

Target‐to‐target interval versus probability effects on P300 in one‐ and two‐tone tasks

The P3(00) is an electrophysiological index of neural processing that varies with such stimulus parameters as interstimulus interval (ISI) and target probability, with a common view being that it reflects an endogenous form of memory update. Building on previous research, we argue that relations between P3 amplitude and both ISI and probability may be attributable to the target-to-target interval (TTI). Employing between-subject (Experiment 1; N = 24) and within-subject (Experiment 2; N = 10) designs, the present paper addresses this by testing subjects on a standard two-tone auditory oddball task as well as a one-tone task. In both studies, P3 amplitude increased and latency decreased linearly with TTI, and these relations were relatively unaffected by ISI or probability. This suggests that ISI and probability per se do not independently affect P3 amplitude, and that TTI offers a strong explanation of the reported relations between P3 amplitude and both ISI and probability.

Target and non-target ERP disturbances in first episode vs. chronic schizophrenia

OBJECTIVES Event-related potential (ERP) abnormalities to target stimuli are reliably found in schizophrenia. However, as people with schizophrenia are thought to have difficulty discerning the relevance of incoming sensory stimuli it is also important to examine ERPs to non-targets. To differentiate between potential trait markers of the disease and deficits that might be associated with the consequence of illness chronicity, this study investigated ERPs to both target and non-target stimuli in groups of people with either first episode or chronic schizophrenia (CSz). METHODS Using an auditory oddball paradigm, ERPs to target, non-target before target (Nt before) and non-target after target (Nt after) stimuli were analysed for 40 patients with CSz, 40 patients with first episode schizophrenia (FESz) and two groups of normal controls matched for age and sex with their patient counterparts. RESULTS The FESz group showed the same pattern of amplitude disturbance as the CSz group to both targets (reduced N100, N200, P300 and increased P200) and non-targets (reduced N100) compared to controls. Both CSz and FESz groups also failed to show the changes to the P200-N200 component between targets and non-target stimuli that was exhibited by controls (smaller earlier P200 to targets vs. increased delayed P200 to non-targets) or the reduction in N100 amplitude of ERPs to the Nt after stimuli compared with ERPs to the Nt before stimuli. Previous literature has focussed on the sensitivity of P300 deficits in classifying persons into schizophrenia and non-schizophrenia groups. This study demonstrated improved accuracy in the classification of patients with schizophrenia from controls using discriminant analysis of target and non-target N100 and P200 components. CONCLUSIONS The results suggest that ERP disturbances are evident at the time of first referral to mental health services and may be a potential trait (rather than secondary effect) of the illness. It is important to include both target and non-target stimuli processing, and their interrelationship in future research.

Is the target-to-target interval a critical determinant of P3 amplitude?

The P3 amplitude is augmented by decrements in target-probability, increments in the number of nontargets preceding the target, and extensions of the interstimulus interval (ISI). Each of these changes prolongs the target-to-target interval (TTI) and, consequently, results attributed to these factors might, at least partially, be accounted for by the TTI. Recent research also indicates that the P3s elicited by targets in one-, two-, and three-stimuli tasks (in which the TTI remains invariant) are similar. However, the TTI has not been examined systematically in previous research. The present study had subjects listen to a randomized ISI (0.5, 1, 2, or 4 s) version of the auditory oddball task in which targets occurred after one, two, three, four, or five nontargets. Event-related potentials were analyzed based on ISI, sequential structure, and TTI. The study examined sequence and ISI effects independent of TTI effects and demonstrated that extensions of ISI affected N1 but not P3 amplitude, extensions of TTI enhanced P3 amplitude independent of sequential structure, and sequential structure failed to influence P3 amplitude when TTI was controlled.

Clinical supervisor training in Australia: A review of current problems and possible solutions

Clinical supervision cuts to the heart of professional psychology training. It is the most expensive single investment of staff time in the training of the psychology practitioner, and it appears to be the single most important contributor to training effectiveness, repaying that investment. Now there are changes afoot internationally which may change its pivotal role. For example, the Psychology Board of Australia has recently proposed that supervisors undergo approved supervisor training; in the USA, a competence-based emphasis is gaining ground; while in the UK, supervisors within the Improving Access to Psychological Therapies initiative are receiving unprecedented training and support. It is therefore timely to clarify the need for such training and to consider promising options for its effective delivery. Following a summary of the changes within Australia, we next address these emergent problems and promising solutions by examining the available scientific evidence and by considering professional consensus statements.

Fatigue and psychological disorders in chronic hepatitis C.

Background and Aim Most patients with chronic hepatitis C report that they suffer from fatigue. The aim of this study was to determine if the symptom of fatigue can be a guide to indicate disease activity in chronic hepatitis C, or if it is related to psychological factors.