California Licensed Psychologist #26429
Honors & Awards
Seed-grant Award, Stanford’s Center for Cognitive and Neurobiological Imaging (CNI) (2015)
Post Doctoral Fellowship, Stanford University, Clinical Fellowship in Pediatric Psychology (2012)
Doctor of Philosophy, Alliant International Universi (2011)
APA Internship, Children's Hospital Colorado, Child and Adolescent Psychology (2011)
Current Research and Scholarly Interests
Research interests include examining the neurodevelopmental aspects of interoception and its influence on emotion processing, empathy and mentalization/theory of mind disturbances across various child and adolescent psychiatric/neurogenetic disorders.
I also hope to translate these findings into new treatments and/ or compensatory strategies that specifically target interoceptive processing, emotional processing and improve interpersonal relationships in children and adolescents.
Neural Correlates of Self-Injurious Behavior in Prader-Willi Syndrome
HUMAN BRAIN MAPPING
2015; 36 (10): 4135-4143
Individuals with Prader-Willi syndrome (PWS), a genetic disorder caused by mutations to the q11-13 region on chromosome 15, commonly show severe skin-picking behaviors that can cause open wounds and sores on the body. To our knowledge, however, no studies have examined the potential neural mechanisms underlying these behaviors. Seventeen individuals with PWS, aged 6-25 years, who showed severe skin-picking behaviors, were recruited and scanned on a 3T scanner. We used functional magnetic resonance imaging (fMRI) while episodes of skin picking were recorded on an MRI-safe video camera. Three participants displayed skin picking continuously throughout the scan, three participants did not display skin picking, and the data for one participant evidenced significant B0 inhomogeneity that could not be corrected. The data for the remaining 10 participants (six male, four female) who displayed a sufficient number of picking and nonpicking episodes were subjected to fMRI analysis. Results showed that regions involved in interoceptive, motor, attention, and somatosensory processing were activated during episodes of skin-picking behavior compared with nonpicking episodes. Scores obtained on the Self-Injury Trauma scale were significantly negatively correlated with mean activation within the right insula and left precentral gyrus. These data indicate that itch and pain processes appear to underlie skin-picking behaviors in PWS, suggesting that interoceptive disturbance may contribute to the severity and maintenance of abnormal skin-picking behaviors in PWS. Implications for treatments are discussed. Hum Brain Mapp, 2015. © 2015 Wiley Periodicals, Inc.
View details for DOI 10.1002/hbm.22903
View details for Web of Science ID 000364219100031
View details for PubMedID 26173182
- Examining the neural correlates of emergent equivalence relations in fragile X syndrome PSYCHIATRY RESEARCH-NEUROIMAGING 2015; 233 (3): 373-379
- Posttraumatic Stress and Age Variation in Amygdala Volumes among Youth Exposed to Trauma Social Cognitive and Affective Neuroscience 2015
Interoceptive sensitivity deficits in women recovered from bulimia nervosa
2013; 14 (4): 488-492
Self-report studies suggest that patients with bulimia nervosa (BN) evidence difficulties with interoceptive awareness. Indeed, interoceptive deficits may persist after recovery of BN and may be a biological trait that predisposes symptom development in BN. However, no studies to date have directly assessed interoceptive sensitivity, or accuracy in detecting and perceiving internal body cues, in patients with or recovered from BN. Nine women who had recovered from BN and 10 healthy control women completed the Heart Beat Perception Task (HBPT) in which individuals were required to estimate the number of heartbeats between intervals of time. Accuracy scores were compared between groups. Significant differences were found between the groups on the HBPT ((F1,19) = 7.78, p = .013, Cohen's d = 1.16) when controlling for age. These results suggest that deficits in interoceptive sensitivity are present in individuals recovered from BN. Thus interoceptive deficits may be one factor that bridges the gap between brain dysfunction and symptom presentation in BN.
View details for DOI 10.1016/j.eatbeh.2013.08.002
View details for Web of Science ID 000327363100017
View details for PubMedID 24183142
Central coherence in adolescents with bulimia nervosa spectrum eating disorders
INTERNATIONAL JOURNAL OF EATING DISORDERS
2015; 48 (5): 487-493
Weak central coherence-a tendency to process details at the expense of the gestalt-has been observed among adults with bulimia nervosa (BN) and is a potential candidate endophenotype for eating disorders (EDs). However, as BN behaviors typically onset during adolescence it is important to assess central coherence in this younger age group to determine whether the findings in adults are likely a result of BN or present earlier in the evolution of the disorder. This study examines whether the detail-oriented and fragmented cognitive inefficiency observed among adults with BN is observable among adolescents with shorter illness duration, relative to healthy controls.The Rey-Osterrieth Complex Figure Test (RCFT) was administered to a total of 47 adolescents with DSM5 BN, 42 with purging disorder (PD), and 25 healthy controls (HC). Performance on this measure was compared across the three groups.Those with BN and PD demonstrated significantly worse accuracy scores compared to controls in the copy and delayed recall condition with a moderate effect size. These findings were exacerbated when symptoms of BN increased.Poorer accuracy scores reflect a fragmented and piecemeal strategy that interferes with visual-spatial integration in BN spectrum disorders. This cognitive inefficiency likely contributes to broad difficulties in executive functioning in this population especially in the context of worsening bulimic symptoms. The findings of this study support the hypothesis that poor global integration may constitute a cognitive endophenotype for BN.
View details for DOI 10.1002/eat.22340
View details for Web of Science ID 000356684500006
- Second-Generation Antipsychotic Drugs in Anorexia Nervosa: A Meta-Analysis of Randomized Controlled Trials PSYCHOTHERAPY AND PSYCHOSOMATICS 2015; 84 (2): 110-116
Altered insula activation during pain anticipation in individuals recovered from anorexia nervosa: Evidence of interoceptive dysregulation
INTERNATIONAL JOURNAL OF EATING DISORDERS
2013; 46 (1): 23-33
Recent evidence raises the possibility that symptoms of anorexia nervosa (AN) could be related to impaired interoception. Pain is an interoceptive process with well-characterized neuroanatomical pathways that may overlap to a large degree with neural systems that may be dysregulated in individuals with AN, such as the insula.Functional magnetic resonance imaging (fMRI) was used to assess neural substrates of pain anticipation and processing in 10 healthy control women (CW) and 12 individuals recovered from AN (REC AN) in order to avoid the confounding effects of malnutrition. Painful heat stimuli were applied while different colors signaled the intensity of the upcoming stimuli.REC AN compared with CW showed greater activation within right anterior insula (rAI), dorsolateral prefrontal cortex (dlPFC) and cingulate during pain anticipation, and greater activation within dlPFC and decreased activation within posterior insula during painful stimulation. Greater anticipatory rAI activation correlated positively with alexithymic feelings in REC AN participants.REC AN showed a mismatch between anticipation and objective responses, suggesting altered integration and, possibly, disconnection between reported and actual interoceptive state. Alexithymia assessment provided additional evidence of an altered ability to accurately perceive bodily signals in women recovered from AN.
View details for DOI 10.1002/eat.22045
View details for Web of Science ID 000312300000004
View details for PubMedID 22836447
Double-Blind Placebo-Controlled Trial of Quetiapine in Anorexia Nervosa
EUROPEAN EATING DISORDERS REVIEW
2012; 20 (4): 331-334
Our objective is to determine whether quetiapine was superior to placebo in increasing weight or reducing core symptoms of anorexia nervosa as assessed by the Yale-Brown-Cornell Eating Disorder Scale and the Eating Disorder Inventory-2.Participants were randomised to 8 weeks of quetiapine or placebo.There are 21 participants who signed informed consent, 15 were randomised, 14 returned for at least one visit after receiving drug and 10 completed the study. There were no differences between drug and placebo in questionnaire scores, weight or measures of anxiety or depression.There was no difference between quetiapine and placebo on weight gain or core symptoms. Small effect sizes suggest that a higher number of participants would not increase significant differences between groups.
View details for DOI 10.1002/erv.2169
View details for Web of Science ID 000305507100012
View details for PubMedID 22535517
Differential Weight Restoration on Olanzapine versus Fluoxetine in Identical Twins with Anorexia Nervosa
INTERNATIONAL JOURNAL OF EATING DISORDERS
2012; 45 (2): 294-297
No studies have compared the response to selective serotonin reuptake inhibitors and atypical antipsychotics in anorexia nervosa. This case study examines such a comparison.This report describes a case of 12-year-old identical twins with anorexia nervosa, one of whom was treated with olanzapine and the other with fluoxetine, while undergoing family therapy.Twin A treated with fluoxetine went from 75 to 84.4% ideal body weight, while Twin B treated with olanzapine went from 72 to 99.9% ideal body weight over the course of 9 months.This case supports the need for adequately powered, controlled clinical trials to test the efficacy of olanzapine in adolescents presenting with anorexia nervosa.
View details for DOI 10.1002/eat.20917
View details for Web of Science ID 000301228500018
View details for PubMedID 21344468
- Is Anorexia Nervosa an Eating Disorder? How Neurobiology Can Help Understand Puzzling Behaviors A Collaborative Approach to Eating Disorders: Routledge 2011