The MATRICS consensus cognitive battery for the assessment of cognitive impairment in schizotypal personality disorder.

Cognitive deficits are a core impairment across the range of schizophrenia (SZ) spectrum disorders, including schizotypal personality disorder (SPD). The MATRICS Consensus Cognitive Battery (MCCB) was developed to be a robust, specific, and valid cognitive assessment battery to assess cognition in clinical trials for treating cognitive impairments in SZ. Despite the similarity of cognitive impairments shown in SPD and SZ and the clear relevance of uniform assessment across a diagnostic spectrum, the MCCB has yet to be validated in SPD. As such, this is the first study to evaluate the sensitivity of the MCCB for the assessment of cognitive function in individuals with SPD. Participants were 30 individuals with SPD and 54 healthy controls (HC) assessed with the MCCB and supplemental neurocognitive assessments (Trails B, DOT test, Paced Auditory Serial Addition Test (PASAT), AX Continuous Performance Task (AX-CPT), and N-back). Individuals with SPD performed worse than HC participants on all MCCB subtests, as well as on converging supplemental tasks including Trails B, DOT test, PASAT, AX-CPT, and N-back. These results indicate that the MCCB was sensitive to cognitive impairment in SPD compared to controls. SPD participants demonstrate impairments similar to data of SZ participants within the literature, although to a slightly lesser degree of severity. Taken together, these results highlight the generalizability of using the MCCB across SZ spectrum diagnostic groups to assess cognition. Such findings allow for further comparison across disorders, greater understanding of the cognitive characteristics in the spectrum, and use of uniform assessment within cognitive intervention research.

Training in Cognitive Reappraisal Normalizes Whole-Brain Indices of Emotion Regulation in Borderline Personality Disorder.

BACKGROUND: Borderline personality disorder (BPD) is the prototypical disorder of emotion dysregulation. We have previously shown that patients with BPD are impaired in their capacity to engage cognitive reappraisal, a frequently employed adaptive emotion regulation strategy. METHODS: Here, we report on the efficacy of longitudinal training in cognitive reappraisal to enhance emotion regulation in patients with BPD. Specifically, the training targeted psychological distancing, a reappraisal tactic whereby negative stimuli are viewed dispassionately as though experienced by an objective, impartial observer. At each of 5 sessions over 2 weeks, 22 participants with BPD (14 female) and 22 healthy control participants (13 female) received training in psychological distancing and then completed a widely used picture-based reappraisal task. Self-reported negative affect ratings and functional magnetic resonance imaging data were acquired at the first and fifth sessions. In addition to behavioral analyses, we performed whole-brain pattern expression analyses using independently defined patterns for negative affect and cognitive reappraisal implementation for each session. RESULTS: Patients with BPD showed a decrease in negative affect pattern expression following reappraisal training, reflecting a normalization in neural activity. However, they did not show significant change in behavioral self-reports. CONCLUSIONS: To our knowledge, this study represents the first longitudinal functional magnetic resonance imaging examination of task-based cognitive reappraisal training. Using a brief, proof-of-concept design, the results suggest a potential role for reappraisal training in the treatment of patients with BPD.

Clinical features of individuals with schizotypal personality disorder with and without suicidal ideation.

This study compared demographic and clinical features in a sample of 384 participants: healthy controls (HC; n = 166) and individuals with schizotypal personality disorder (SPD) with (n = 50) and without (n = 168) suicidal ideation (SI) to examine specific risk factors for suicidality in SPD. Compared to the non-SI group, the SI group showed significantly greater severity of depression, aggression, impulsivity, affective lability, schizotypal features, poorer social adjustment, and had fewer social contacts. Individuals in the SI group were also more likely to have a history of a suicide attempt and comorbid borderline personality disorder in comparison to the non-SI group. Logistic regression analysis indicated that severity of depression and the number of social contacts drove the difference between the SI and non-SI groups. Compared with both SPD subgroups, the HC group was significantly less depressed, aggressive, impulsive, affectively labile, had fewer schizotypal features, was better socially adjusted, and had more social contacts. This study indicates that overall, the SI group is a more severely impaired group of individuals with SPD compared to the non-SI group. Better educating medical professionals about the diagnosis and management of SPD and its associations with suicidality is warranted.

The structure of antagonism: A hierarchical model of self- and interview-rated psychopathology.

Recent initiatives in the empirically based classification of psychopathology, namely, the Hierarchical Taxonomy of Psychopathology (HiTOP), have made significant strides in addressing the limitations of traditional taxonomies (i.e., Diagnostic and Statistical Manual of Mental Disorders, International Classification of Diseases). The current study aimed to extend this work by helping to clarify the lower order structure of an understudied dimension of psychopathology-antagonism (i.e., HiTOP antagonistic externalizing spectrum)-a core feature of many externalizing disorders and related to important outcomes such as interpersonal problems, childhood conduct problems, and incarceration. We examined the hierarchical structure of several measures of antagonistic externalizing features across both self-report and clinical interview ratings for 2,279 community participants with a diverse range of personality pathology (~75% with a personality disorder) and antagonistic behaviors (~30% with intermittent explosive disorder). Exploratory structural equation modeling was used to account for the shared variance between variables within self-report and interview methods. Results revealed an optimal lower order structure consisting of six factors labeled Antisociality, Anger, Hostility, Narcissism, Mistrust, and Attention Seeking. Factor scores yielded expected relations with self-report and interview ratings of psychopathology, personality, and childhood trauma. Implications for future research in classification and treatment of psychopathology are discussed. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Serotonin transporter availability in physically aggressive personality disordered patients: associations with trait and state aggression, and response to fluoxetine.

RATIONALE: Characterizing the neuroanatomical basis of serotonergic abnormalities in severe, chronic, impulsive aggression will allow for rational treatment selection, development of novel therapeutics, and biomarkers to identify at-risk individuals. OBJECTIVES: The aim of this study is to identify associations between regional serotonin transporter (5-HTT) availability and trait and state aggression, as well as response to the anti-aggressive effects of fluoxetine. METHODS: We examined 5-HTT availability using positron emission tomography (PET) imaging with [11C]DASB in personality disordered patients with current physical intermittent explosive disorder (IED; n = 18), and healthy comparison participants (HC; n = 11), in the anterior cingulate cortex (ACC), amygdala (AMY), ventral striatum (VST), and midbrain (MID). After PET imaging, IED patients were treated with fluoxetine 20 mg daily (n = 9) or placebo (n = 6) for 12 weeks. Trait and state aggression, trait callousness, and childhood trauma were assessed. RESULTS: In IED patients, trait aggression was positively associated with [11C]DASB binding in the ACC and VST; covarying for trait callousness and childhood trauma enhanced these correlations. Baseline state aggression was positively correlated with ACC [11C]DASB in IED patients. Greater baseline VST [11C]DASB binding predicted greater decreases in state aggression with fluoxetine treatment. CONCLUSIONS: Consistent with prior reports, ACC 5-HTT is related to trait aggression, and adjusting for factors related to proactive (callousness) and reactive (childhood trauma) aggression subtypes further resolves this relationship. Novel findings of the study include a better understanding of the association between regional 5-HTT availability and state aggression, and the involvement of VST 5-HTT with trait aggression, and with the anti-aggressive effects of fluoxetine.

Borderline personality disorder.

Recent research findings have contributed to an improved understanding and treatment of borderline personality disorder. This disorder is characterised by severe functional impairments, a high risk of suicide, a negative effect on the course of depressive disorders, extensive use of treatment, and high costs to society. The course of this disorder is less stable than expected for personality disorders. The causes are not yet clear, but genetic factors and adverse life events seem to interact to lead to the disorder. Neurobiological research suggests that abnormalities in the frontolimbic networks are associated with many of the symptoms. Data for the effectiveness of pharmacotherapy vary and evidence is not yet robust. Specific forms of psychotherapy seem to be beneficial for at least some of the problems frequently reported in patients with borderline personality disorder. At present, there is no evidence to suggest that one specific form of psychotherapy is more effective than another. Further research is needed on the diagnosis, neurobiology, and treatment of borderline personality disorder.

Hyperreactivity and Impaired Habituation of Startle Amplitude During Unpleasant Pictures in Borderline but Not Schizotypal Personality Disorder: Quantifying Emotion Dysregulation.

BACKGROUND: Borderline personality disorder (BPD) is characterized by greater intensity of reactions to unpleasant emotional cues and a slower-than-normal return of these responses to baseline. Habituation is defined as decreased response to repeated stimulation. Affect-modulated startle (AMS), a translational psychophysiological approach, is mediated by the amygdala and used to study emotion processing in both humans and animals. This is the first study to examine the specificity of habituation anomalies in BPD during passive emotional and neutral picture processing. METHODS: A total of 90 participants were studied: patients with BPD (n = 35), patients with schizotypal personality disorder (n = 26; included as a psychopathological comparison group), and healthy control subjects (n = 29). Participants received rigorous clinical assessments, and patients were unmedicated. AMS was examined during a series of intermixed unpleasant, neutral, and pleasant pictures. RESULTS: Compared with the other groups, patients with BPD showed greater overall AMS during unpleasant pictures and prolonged habituation of startle amplitude during unpleasant pictures from early to later trials. The groups did not differ in AMS during neutral or pleasant pictures or self-reported picture valence. Among the patients with BPD, prolonged habituation to unpleasant pictures was associated with greater symptom severity and suicidal/self-harming behavior. CONCLUSIONS: These findings 1) indicate that abnormal processing of and habituation to unpleasant pictures is observed in BPD but not schizotypal personality disorder, suggesting that these deficits are not simply characteristics of personality disorders in general; 2) are consistent with studies showing deficient amygdala habituation to unpleasant pictures in BPD; and 3) have significant implications for clinical assessment and treatment of BPD, e.g., alternative therapies for BPD such as gradual exposure to unpleasant emotional stimuli or amygdala neurofeedback may aid habituation deficits.

Frontotemporal thalamic connectivity in schizophrenia and schizotypal personality disorder.

Schizotypal personality disorder (SPD) resembles schizophrenia, but with attenuated brain abnormalities and the absence of psychosis. The thalamus is integral for processing and transmitting information across cortical regions and widely implicated in the neurobiology of schizophrenia. Comparing thalamic connectivity in SPD and schizophrenia could reveal an intermediate schizophrenia-spectrum phenotype to elucidate neurobiological risk and protective factors in psychosis. We used rsfMRI to investigate functional connectivity between the mediodorsal nucleus (MDN) and pulvinar, and their connectivity with frontal and temporal cortical regions, respectively in 43 healthy controls (HCs), and individuals in the schizophrenia-spectrum including 45 psychotropic drug-free individuals with SPD, and 20 individuals with schizophrenia-related disorders [(schizophrenia (n = 10), schizoaffective disorder (n = 8), schizophreniform disorder (n = 1) and psychosis NOS (n = 1)]. Individuals with SPD had greater functional connectivity between the MDN and pulvinar compared to individuals with schizophrenia. Thalamo-frontal (i.e., between the MDN and rostral middle frontal cortex) connectivity was comparable in SPD and HCs; in SPD greater connectivity was associated with less symptom severity. Individuals with schizophrenia had less thalamo-frontal connectivity and thalamo-temporal (i.e., pulvinar to the transverse temporal cortex) connectivity compared with HCs. Thalamo-frontal functional connectivity may be comparable in SPD and HCs, but abnormal in schizophrenia, and that this may be protective against psychosis in SPD.

Cingulate and temporal lobe fractional anisotropy in schizotypal personality disorder.

BACKGROUND: Consistent with the clinical picture of milder symptomatology in schizotypal personality disorder (SPD) than schizophrenia, morphological studies indicate SPD abnormalities in temporal lobe regions but to a much lesser extent in prefrontal regions implicated in schizophrenia. Lower fractional anisotropy (FA), a measure of white-matter integrity within prefrontal, temporal, and cingulate regions has been reported in schizophrenia but has been little studied in SPD. AIMS: The study aim was to examine temporal and prefrontal white matter FA in 30 neuroleptic-naïve SPD patients and 35 matched healthy controls (HCs). We hypothesized that compared with HCs, SPD patients would exhibit lower FA in temporal lobe and anterior cingulum regions but relative sparing in prefrontal regions. METHOD: We acquired diffusion tensor imaging (DTI) in all participants and examined FA in the white matter underlying Brodmann areas (BAs) in dorsolateral prefrontal (BAs 44, 45, and 46), temporal lobe (BAs 22, 21, and 20), and cingulum (BAs 25, 24, 31, 23, and 29) regions with a series of analyses using multivariate analysis of variance. RESULTS: Compared with HCs, the SPD group had significantly lower FA in the left temporal lobe but not prefrontal regions. In the cingulum, FA was lower in the SPD group in the posterior regions (BAs 31 and 23), higher in the anterior (BA 25) regions and lower overall in the right but not the left cingulum. Among the SPD group, lower FA in the cingulum was associated with more severe negative symptoms (e.g., odd speech). CONCLUSIONS: Similar to schizophrenia, our results indicate cingulum-temporal lobe FA abnormalities in SPD and suggest that cingulum abnormalities are associated with negative symptoms.

Anomalous Amygdala Habituation to Unpleasant Stimuli Among Unmedicated Individuals With Borderline Personality Disorder and a History of Self-Harming Behavior.

Self-harming behavior (SB) is one of the diagnostic criteria for borderline personality disorder (BPD). However, it is not exhibited by all individuals with BPD. Furthermore, studies examining the neural correlates of SB in BPD are lacking. Given research showing that BPD patients have difficulty habituating to affective stimuli, this study investigated whether anomalous amygdala activation is specific to BPD patients with SB. The authors used fMRI to compare amygdala activation in BPD patients with SB (n = 15) to BPD patients without SB (n = 18) and healthy controls (n = 32) during a task involving pleasant, neutral, and unpleasant pictures, presented twice. BPD patients with SB demonstrated greater amygdala activity during the second presentation of unpleasant pictures. Results highlight neurobiological differences in BPD patients with and without SB and suggest that anomalous amygdala habituation to unpleasant stimuli may be related to SB.

Alexithymia, Affective Lability, Impulsivity, and Childhood Adversity in Borderline Personality Disorder.

Long-standing theories of borderline personality disorder (BPD) suggest that symptoms develop at least in part from childhood adversity. Emotion dysregulation may meaningfully mediate these effects. The current study examined three factors related to emotion dysregulation-alexithymia, affective lability, and impulsivity-as potential mediators of the relation between childhood adversity and BPD diagnosis in 101 individuals with BPD and 95 healthy controls. Path analysis compared three distinct models informed by the literature. Results supported a complex mediation model wherein (a) alexithymia partially mediated the relation of childhood adversity to affective lability and impulsivity; (b) affective lability mediated the relation of childhood adversity to BPD diagnosis; and (c) affective lability and impulsivity mediated the relation of alexithymia to BPD diagnosis. Findings suggest that affective lability and alexithymia are key to understanding the relationship between childhood adversity and BPD. Interventions specifically targeting affective lability, impulsivity, and alexithymia may be particularly useful for this population.

Amphetamine-induced striatal dopamine release in schizotypal personality disorder.

RATIONALE: Previous research has suggested that schizotypal personality disorder (SPD), a condition that shares clinical and cognitive features with schizophrenia, may be associated with elevated striatal dopamine functioning; however, there are no published studies of dopamine release within subregions of the striatum in SPD. OBJECTIVES: To characterize dopamine release capacity in striatal subregions and its relation to clinical and cognitive features in SPD. METHODS: We used positron emission tomography with [11C]raclopride and an amphetamine challenge to measure dopamine D2-receptor availability (binding potential, BPND), and its percent change post-amphetamine (∆BPND) to index amphetamine-induced dopamine release, in subregions of the striatum in 16 SPD and 16 healthy control participants. SPD participants were evaluated with measures of schizotypal symptom severity and working memory. RESULTS: There were no significant group differences in BPND or ∆BPND in any striatal subregion or whole striatum. Among SPD participants, cognitive-perceptual symptoms were associated at trend level with ∆BPND in the ventral striatum, and disorganized symptoms were significantly negatively related to ∆BPND in several striatal subregions. CONCLUSIONS: In contrast to previous findings, SPD was not associated with elevated striatal dopamine release. However, in SPD, there was a moderate positive association between ventral striatal dopamine release and severity of cognitive-perceptual symptoms, and negative associations between striatal dopamine release and severity of disorganized symptoms. Future larger scale investigations that allow for the separate examination of subgroups of participants based on clinical presentation will be valuable in further elucidating striatal DA functioning in SPD.

Neural correlates of emotion processing in borderline personality disorder.

Emotional instability is a hallmark feature of borderline personality disorder (BPD), yet its biological underpinnings are poorly understood. We employed functional magnetic resonance imaging (fMRI) to compare patterns of regional brain activation in BPD patients and healthy volunteers as they process positive and negative social emotional stimuli. fMRI images were acquired while 19 BPD patients and 17 healthy controls (HC) viewed emotion-inducing pictures from the International Affective Pictures System set. Activation data were analyzed with SPM5 ANCOVA models to derive the effects of diagnosis and stimulus type. BPD patients demonstrated greater differences in activation than controls, when viewing negative pictures compared with rest, in the amygdala, fusiform gyrus, primary visual areas, superior temporal gyrus (STG), and premotor areas, while healthy controls showed greater differences than BPD patients in the insula, middle temporal gyrus and dorsolateral prefrontal cortex (BA46). When viewing positive pictures compared with rest, BPD patients showed greater differences in the STG, premotor cortex, and ventrolateral prefrontal cortex. These findings suggest that BPD patients show greater amygdala activity and heightened activity of visual processing regions relative to findings for HC subjects in the processing of negative social emotional pictures compared with rest. The patients activate neural networks in emotion processing that are phylogeneticall older and more reflexive than those activated by HC subjects.

Childhood trauma and basal cortisol in people with personality disorders.

This study examined the influence of various forms of childhood abuse on basal cortisol levels in a sample of adults with Axis II personality disorders. Participants included 63 adults (n = 19 women) who provided basal plasma cortisol samples and completed the Childhood Trauma Questionnaire. Linear regression analyses that included all 5 subscales (ie, sexual abuse, physical abuse, emotional abuse, physical neglect and emotional neglect) demonstrated that physical abuse was related to lower cortisol levels (beta = -.43, P = .007), consistent with prior literature. In contrast, physical neglect was associated with higher cortisol (beta = .36, P = .02), after controlling for other forms of abuse. Results are consistent with the view that childhood trauma has long-lasting neurobiological effects and suggest that different forms of trauma may have distinct biological effects.

Neuroimaging predictors of response to cognitive remediation and social skills training: A pilot study in veterans with schizophrenia.

Neuroimaging may predict response to cognitive remediation therapy and social skills training (CRT + SST) in schizophrenia. Identifying biological predictors of response is crucial for treatment decision making given not all patients respond to such interventions. Nineteen veterans with schizophrenia enrolled in an 8-week trial of CRT + SST. Ten participants completed diffusion tensor imaging (DTI) at baseline. Baseline fractional anisotropy (FA) in the superior longitudinal fasciculus (SLF) and overall average FA predicted improvements in visual-spatial working memory, and social cognition, respectively. Neuroimaging may be useful in identifying therapeutic targets in schizophrenia.

Guanfacine Augmentation of a Combined Intervention of Computerized Cognitive Remediation Therapy and Social Skills Training for Schizotypal Personality Disorder.

OBJECTIVE: Impaired cognition is a hallmark of schizophrenia spectrum disorders, including schizotypal personality disorder, and it is the best predictor of functional outcome. Cognitive remediation therapy has demonstrated efficacy for improving cognition, augmenting other rehabilitation efforts in schizophrenia, and effecting gains in real-world functioning. Pharmacological augmentation of cognitive remediation has been attempted, but the effects of augmentation on combined therapies, such as cognitive remediation and social skills training, have not been studied. METHODS: Twenty-eight participants with schizotypal personality disorder enrolled in an 8-week, randomized, double-blind, placebo-controlled trial of guanfacine plus cognitive remediation and social skills training (15 guanfacine, 13 placebo). Cognition was assessed with the MATRICS (Measurement and Treatment Research to Improve Cognition in Schizophrenia) Consensus Cognitive Battery (MCCB), social cognition with the Movie for the Assessment of Social Cognition (MASC), and functional capacity with the University of California San Diego Performance-Based Skills Assessment (UPSA). RESULTS: A statistically significant pre- versus posttreatment effect was observed for MCCB speed of processing, verbal learning, and visual learning and UPSA total score. A significant time-by-medication (guanfacine, placebo) interaction was observed for MCCB reasoning and problem solving and UPSA total score; the time-by-treatment interaction approached significance for MASC hypomentalizing errors. CONCLUSIONS: Both guanfacine and cognitive remediation plus social skills training were well tolerated, with no side effects or dropouts. Participants treated with cognitive remediation, social skills training, and guanfacine demonstrated statistically significant improvements in reasoning and problem solving, as well as in functional capacity and possibly social cognition, compared with those treated with cognitive remediation, social skills training, and placebo. Cognitive remediation plus social skills training may be an appropriate intervention for individuals with schizotypal personality disorder, and guanfacine appears to be a promising pharmaceutical augmentation to this psychosocial intervention.

Short communication: Diffusion tensor anisotropy in the cingulate in borderline and schizotypal personality disorder.

Despite considerable phenomentological differences between borderline personality disorder (BPD) and schizotypal personality disorder (SPD), research increasingly provides evidence that some BPD symptoms overlap with SPD symptoms (e.g., disturbed cognitions). We examined the cingulate, a brain region implicated in the pathophysiology of both disorders, to determine similarities/differences between the groups, and similarities/differences from healthy controls (HC's). 3T structural and diffusion tensor magnetic resonance imaging scans were acquired in BPD (n = 27), SPD (n = 32), HC's (n = 34). Results revealed that BPD patients exhibited significantly lower FA in posterior cingulate white matter compared to HC's (p = 0.04), but SPD patients did not.

Comparison of self-report and clinician-rated schizotypal traits in schizotypal personality disorder and community controls.

Given the common use of self-report questionnaires to assess schizotypy in personality pathology and schizophrenia research, it is important to determine the concordance between self-report and clinician ratings. 250 individuals with schizotypal personality disorder (SPD) and 116 community controls (CTR) were assessed on schizotypal traits using a clinical interview, the Structured Interview for DSM-IV Personality disorders (SIDP), and a self-report questionnaire, the Schizotypal Personality Questionnaire (SPQ). Ordinal logistic regressions examined concordance between self-reported and clinician-rated scores in CTR and SPD separately. Analyses of variance examined how the SPQ performed on differentiating between CTR with low schizotypy, CTR with high schizotypy, and SPD. For both CTR and SPD, higher SPQ subscale scores were significantly associated with higher clinician ratings on the respective SIDP items for the Ideas of Reference, Magical Thinking, Unusual Perceptual Experience, Suspiciousness, and Social Anxiety items, but not the Odd Speech or Limited Affect items. Higher SPQ subscale scores for Odd Behavior and Lack of Close Friends were significantly associated with the clinician-rated SIDP item scores in CTR but not SPD. CTR with low schizotypy scored lower on all SPQ subscales than CTR with high schizotypy, who did not differ from SPD. Self-report ratings are concordant with clinician ratings for positive schizotypal traits, whereas certain disorganization and interpersonal traits are not, particularly for individuals with SPD. The SPQ can differentiate between high and low schizotypy controls, but not between high schizotypy controls and individuals with SPD. Assessment of schizotypal traits should include both self-report questionnaires and clinician ratings.

Frontal-striatal-thalamic mediodorsal nucleus dysfunction in schizophrenia-spectrum patients during sensorimotor gating.

Prepulse inhibition (PPI) refers to a reduction in the amplitude of the startle eyeblink reflex to a strong sensory stimulus, the pulse, when it is preceded shortly by a weak stimulus, the prepulse. PPI is a measure of sensorimotor gating which serves to prevent the interruption of early attentional processing and it is impaired in schizophrenia-spectrum patients. In healthy individuals, PPI is more robust when attending to than ignoring a prepulse. Animal and human work demonstrates that frontal-striatal-thalamic (FST) circuitry modulates PPI. This study used functional magnetic resonance imaging (fMRI) to investigate FST circuitry during an attention-to-prepulse paradigm in 26 unmedicated schizophrenia-spectrum patients (13 schizotypal personality disorder (SPD), 13 schizophrenia) and 13 healthy controls. During 3T-fMRI acquisition and separately measured psychophysiological assessment of PPI, participants heard an intermixed series of high- and low-pitched tones serving as prepulses to an acoustic-startle stimulus. Event-related BOLD response amplitude curves in FST regions traced on co-registered anatomical MRI were examined. Controls showed greater activation during attended than ignored PPI conditions in all FST regions-dorsolateral prefrontal cortex (Brodmann areas 46, 9), striatum (caudate, putamen), and the thalamic mediodorsal nucleus. In contrast, schizophrenia patients failed to show differential BOLD responses in FST circuitry during attended and ignored prepulses, whereas SPD patients showed greater-than-normal activation during ignored prepulses. Among the three diagnostic groups, lower left caudate BOLD activation during the attended PPI condition was associated with more deficient sensorimotor gating as measured by PPI. Schizophrenia-spectrum patients exhibit inefficient utilization of FST circuitry during attentional modulation of PPI. Schizophrenia patients have reduced recruitment of FST circuitry during task-relevant stimuli, whereas SPD patients allocate excessive resources during task-irrelevant stimuli. Dysfunctional FST activation, particularly in the caudate may underlie PPI abnormalities in schizophrenia-spectrum patients.