Khalima Bolden | University of California, Davis (original) (raw)

Papers by Khalima Bolden

JAMA Psychiatry, Jan 4, 2023

NeuroImage: Clinical, 2021

Highlights • Attentional control measured in 22q youth and typically developing control group.• D... more Highlights • Attentional control measured in 22q youth and typically developing control group.• Differences in attentional control indexed by N2pc and PD event-related potentials.• 22q youth exhibited sustained focus on distractor cues and reduced suppression.• No relationships between attentional control and psychosis-proneness in 22q youth.

American Journal of Medical Genetics Part A, 2020

Behavioral components of chromosome 22q11.2 deletion syndrome (22q), caused by the most common hu... more Behavioral components of chromosome 22q11.2 deletion syndrome (22q), caused by the most common human microdeletion, include cognitive and adaptive functioning impairments, heightened anxiety, and an elevated risk of schizophrenia. We investigated how interactions between executive function and the largely overlooked factor of emotion regulation might relate to the incidence of symptoms of psychotic thinking in youth with 22q. We measured neural activity with event-related potentials (ERPs) in variants of an inhibitory function (Go/No-Go) experimental paradigm that

Schizophrenia Bulletin, 2020

Background Previous studies have shown that African Americans are more likely than Caucasians to ... more Background Previous studies have shown that African Americans are more likely than Caucasians to receive a diagnosis of schizophrenia. Once diagnosed, African Americans are slower to seek treatment, more likely to underutilize mental health services, tend to display lower rates of medication adherence, and respond more slowly to psychosocial interventions. This disparity in diagnoses is due to multiple factors. One notable issue is the under-diagnosis of mood symptoms in African Americans with psychosis. Specifically, studies have shown that African Americans are more likely than Caucasians to receive a non-affective psychosis diagnosis, even though the rates of current mood episodes between the Caucasians and African Americans are similar. This is seen more with regards to depressive symptoms than those of mania. These disparities in diagnosis may contribute to decreased treatment efficacy, erosion of trust in treatment providers, and increased attrition in African Americans. There...

Journal of Psychiatric Research, 2019

Bullying is an adverse childhood experience that is more common among youth with special needs an... more Bullying is an adverse childhood experience that is more common among youth with special needs and is associated with increased psychopathology throughout the lifespan. Individuals with chromosome 22q11.2 deletion syndrome (22q) represent one group of special needs youth who are at increased risk for bullying due to co-occurring genetically-mediated developmental, physical, and learning difficulties. Furthermore, individuals with 22q are at increased risk for developing psychotic disorders such as schizophrenia. However, there is a paucity of research exploring the impact of bullying on individuals with 22q and the possible impact this has on risk for psychosis in this population. To explore this relationship using existing research the goals of the review are: (i) to explore the nature of bullying among youth with special needs, and (ii) to discuss its potential role as a specific risk factor in the development of adverse outcomes, including psychosis symptoms. We reviewed the relationship between bullying and its short and long-term effects on the cognitive, social, and developmental functioning of typically developing individuals and those with special needs. We propose an interactive relationship between trauma, stress, and increased psychosis risk among youth with 22q with a history of bullying. The early childhood experience of trauma in the form of bullying promotes an altered developmental trajectory that may elevate the risk for maladaptive functioning and subsequent psychotic disorders, particularly in youth with genetic vulnerabilities. Therefore, we conclude the experience of bullying among individuals with 22q should be more closely examined.

License, which permits unrestricted use, distribution, and reproduction in any medium, provided t... more License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. This study investigated implicit socioemotional modulation of working memory (WM) in the context of symptom severity and functional status in individuals with psychosis (

Schizophrenia Bulletin, 2017

investigated differences in volumetry between manual delineation and automated segmentations deri... more investigated differences in volumetry between manual delineation and automated segmentations derived by FreeSurfer, FSL, and MAGeT in a sample of first-episode psychosis (FEP) patients and controls. Methods: The basal ganglia and thalamus of 30 subjects (15 FEP, 15 controls) were manually defined and compared to automated methods by extracting: (1) percent volume differences between manual volumes and those derived by MAGeT/FreeSurfer/FSL, (2) between-method correlations, and (3) Bland-Altman plots to illustrate potential biases. Volume and shape differences of the basal ganglia and thalamus were also examined in a larger sample of 135 FEP patients and 88 controls across automated techniques. Results: All automated methods overestimated volumes compared to manual segmentations, with the least pronounced differences produced with MAGeT. The least between-method variability was noted for the striatum, whereas marked differences between manual labels and MAGeT compared to FreeSurfer and FSL emerged for the pallidum and thalamus. Correlations between manual segmentation and automated methods were strongest for MAGeT (range: 0.51-0.92; P < .01, corrected), whereas FreeSurfer and FSL showed moderate to strong Pearson correlations (range: 0.44-0.86; P < .05, corrected), with the exception of FreeSurfer pallidal (r = 0.31, P = .10) and FSL thalamic segmentations (r = 0.37, P = .051). Bland-Altman plots highlighted a tendency for greater volumetric differences between manual labels and automated methods at the lower end of the distribution (ie, smaller structures), which was most prominent for bilateral thalamus across automated pipelines, and left pallidum for FSL. The striatum and pallidum were significantly larger in FEP patients compared to controls bilaterally, irrespective of method. MAGeT was more sensitive to shape-based group differences, and uncovered widespread surface expansions in the striatum and pallidum bilaterally in FEP patients compared to controls, and contractions in bilateral thalamus (FDR corrected). By contrast, FSL only detected differences in the right ventral striatum (FEP > control, corrected) and one cluster of the left thalamus (Control > FEP, corrected). Conclusion: The current study provides a detailed analysis of how manual segmentations of the basal ganglia and thalamus compare against 3 automated segmentation pipelines, namely MAGeT, FreeSurfer, and FSL, in the clinical investigation of changes in subcortical structures in FEP. Results obtained with automated pipelines should be rigorously checked by a trained eye, and consistent quality control procedures are strongly encouraged when using automated segmentation methods.

Journal of Clinical and Experimental Neuropsychology, 2014

Apathy is a relatively common psychiatric syndrome in HIV infection, but little is known about it... more Apathy is a relatively common psychiatric syndrome in HIV infection, but little is known about its neural correlates. In the present study, we examined the associations between apathy and diffusion tensor imaging (DTI) indices in key frontal white matter regions in the thalamocorticostriatal circuit, which has been implicated in the expression of apathy. Nineteen participants with HIV infection and 19 demographically comparable seronegative comparison subjects completed the Apathy subscale of the Frontal Systems Behavioral Scale as a part of a comprehensive neuropsychiatric research evaluation. When compared to the seronegative participants, the HIV+ group had significantly more frontal white matter abnormalities. Within HIV+ persons, and as predicted, higher ratings of apathy were associated with greater white matter alterations in the anterior corona radiata, genu, and orbital medial prefrontal cortex. The associations between white matter alterations and apathy were independent of depression and were stronger among participants with lower current cluster of differentiation 4 (CD4) counts. All told, these findings indicate that apathy is independently associated with white matter abnormalities in anterior, medial brain regions in persons infected with HIV, particularly in the setting of lower current immune functioning, which may have implications for antiretroviral therapy.

Early Intervention in Psychiatry, 2019

Duration of untreated psychosis, or the time between onset of psychosis symptoms and accurate dia... more Duration of untreated psychosis, or the time between onset of psychosis symptoms and accurate diagnosis and treatment, is a significant predictor of both initial treatment response and long‐term outcomes. As such, efforts to improve rapid identification are key. Because early signs of psychosis commonly emerge in adolescence, schools have the potential to play an important role in the identification of psychosis‐spectrum disorders.

Journal of Clinical Medicine

Psychosis is conceptualized in a neurodevelopmental vulnerability-stress framework, and childhood... more Psychosis is conceptualized in a neurodevelopmental vulnerability-stress framework, and childhood trauma is one environmental factor that can lead to psychotic symptoms and the development of psychotic disorders. Higher rates of trauma are associated with higher psychosis risk and greater symptom frequency and severity, resulting in increased hospitalization rates and demand on outpatient primary care and mental health services. Despite an estimated 70% of individuals in the early stages of psychosis reporting a history of experiencing traumatic events, trauma effects (post-traumatic anxiety or depressive symptoms) are often overlooked in psychosis treatment and current interventions typically do not target commonly comorbid post-traumatic stress symptoms. We presented a protocol for Trauma-Integrated Cognitive Behavioral Therapy for Psychosis (TI-CBTp), an approach to treating post-traumatic stress symptoms in the context of early psychosis care. We provided a brief summary of TI-C...

Drug and Alcohol Dependence, 2014

American Journal of Psychiatry

Addictive behaviors, 2013

Attention-Deficit/Hyperactivity Disorder (ADHD) is widely regarded as a common comorbidity of met... more Attention-Deficit/Hyperactivity Disorder (ADHD) is widely regarded as a common comorbidity of methamphetamine (MA) dependence, but the frequency, persistence, and real-world impact of ADHD among MA users are not known. Four hundred individuals with MA use disorders within 18months of evaluation and 355 non-MA using comparison subjects completed a comprehensive neuropsychiatric research battery, including self-report measures of everyday functioning. In logistic regression models adjusting for potential confounds, lifetime diagnoses of ADHD as determined by a structured clinical interview were significantly more prevalent among the MA participants (21%) versus comparison subjects (6%), particularly the hyperactive and combined subtypes. MA use was also associated with an increased persistence of combined subtype of ADHD into adulthood. Among the MA users, lifetime ADHD diagnoses were uniquely associated with greater concurrent risk of declines in instrumental activities of daily livi...

Schizophrenia Research, 2012

Schizophrenia Research and Treatment, 2014

This study investigated implicit socioemotional modulation of working memory (WM) in the context ... more This study investigated implicit socioemotional modulation of working memory (WM) in the context of symptom severity and functional status in individuals with psychosis ( = 21). A delayed match-to-sample task was modified wherein task-irrelevant facial distracters were presented early and briefly during the rehearsal of pseudoword memoranda that varied incrementally in load size (1, 2, or 3 syllables). Facial distracters displayed happy, sad, or emotionally neutral expressions. Implicit socioemotional modulation of WM was indexed by subtracting task accuracy on nonfacial geometrical distraction trials from facial distraction trials. Results indicated that the amount of implicit socioemotional modulation of high WM load accuracy was significantly associated with negative symptoms ( = 0.63, < 0.01), role functioning ( = −0.50, < 0.05), social functioning ( = −0.55, < 0.01), and global assessment of functioning ( = −0.53, < 0.05). Specifically, greater attentional distraction of high WM load was associated with less severe symptoms and functional impairment. This study demonstrates the importance of the WMsocioemotional interface in influencing clinical and psychosocial functional status in psychosis.

Journal of Substance Use, 2015

Longitudinal cohort studies of HIV and substance use disorders play an important role in understa... more Longitudinal cohort studies of HIV and substance use disorders play an important role in understanding these conditions, but high rates of attrition can threaten their integrity and generalizability. This study aimed to identify factors associated with attrition in a 5-year observational cohort study of 469 individuals with and without HIV infection and methamphetamine (MA) dependence. Rates of attrition in our four study groups were approximately 24% in HIV-MA-, 15% in HIV+MA-, 56% in HIV-MA+, and 47% in HIV+MA+ individuals. Predictors of attrition in the overall cohort included history of MA, alcohol, and other substance dependence, learning impairment, reduced cognitive reserve, and independence in activities of daily living (all ps < .05), but varied somewhat by clinical group. Of particular note, enrollment in a neuroimaging substudy was associated with significantly boosted rates of retention in the MA groups. Results from this investigation highlight the complexity of the clinical factors that influence retention in cohort studies of HIV-infected MA users and might guide the development and implementation of targeted retention efforts.

Psychological Assessment, 2013

As parametric cognitive models become more commonly used to measure individual differences, the c... more As parametric cognitive models become more commonly used to measure individual differences, the construct validity of the interpretation of individual model parameters needs to be well established. The validity of the interpretation of 2 parameters of a formal model of the Continuous Recognition Memory Test (CRMT) was investigated in 2 experiments. The 1st study found that manipulating the percentage of trials on the CRMT for which degraded pseudowords were presented altered the model&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s stimulus encoding parameter but not the working memory displacement parameter. The 2nd experiment showed that manipulating the number of syllables forming a pseudoword altered the model&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s working memory displacement parameter for each syllable added to the pseudoword. Findings from both experiments supported the construct representation of the model parameters, supporting the construct validity of the model&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s use to interpret CRMT performance. Combining parametric models with the manipulation of factors that theory predicts are related to model parameters provides an approach to construct validation that bridges experimental and individual difference methods of studying human…

Journal of the Neurological Sciences, 2013

Journal of Intellectual Disability Research, 2011