Travis Research Institute
Psychology Building 325
Fuller Theological Seminary
180 N. Oakland Ave.
Pasadena, CA 91101-1714
California Institute of Technology
International Research Consortium on the Corpus Callosum and Cerebral Connectivity (IRC5)
National Organization of Disorders of the Corpus Callosum The Brain Recovery Project
The Human Brain and Cognition Laboratory (HBCL) studies the cognitive and psychosocial impact of congenital and acquired disruption of connectivity and cerebral interactivity in disorders such as agenesis of the corpus callosum and hemispherectomy. The cognitive and social abilities that are studied in persons with these disorders include: general intelligence, basic academic skill, memory, language, executive functioning, visual-spatial processing, problem-solving, mental processing speed, personality, emotion, social inference, social problem-solving, creativity, and adaptive skills. Through comprehensive assessment of mental and social skills, our research is providing patients, families, and physicians with critical information about the consequences of hemispheric disconnection and hemispherectomy, which can inform efforts toward remediation and intervention.
AGENESIS OF THE CORPUS CALLOSUM
COGNITIVE AND PSYCHOSOCIAL DEFICITS
What is agenesis of the corpus callosum (ACC):
ACC involves congenital absence of all or part of the corpus callosum – the large connective pathway between the right and left hemispheres of the brain.
Neuropsychological Research on ACC:
Because the disorder can only be firmly diagnosed by neuroimaging, it has a short research history. Over the past 20+ years research by the members of the Human Brain and Cognition Lab have played a major role in understanding the consequences of this disorder for cognitive and social functioning.
How does ACC affect a person?
As a result of this large ongoing research project we have found that the basic syndrome involves (1) Reduced interhemispheric transfer of sensory-motor information; (2) Reduced cognitive processing speed; (3) Deficits in complex reasoning and novel problem-solving. We have also found that these core deficits are expressed as mild to moderate deficiencies across many domains of cognitive, behavioral, and social functioning.
PUBLICATIONS (WITH LINKS):
Brown, W.S., Panos, A. and Paul, L.K. (in press) “Impulsivity, Vigilance and Attention in Agenesis of the Corpus Callosum” Neuropsychology.
This study assessed inattention, impulsivity, and vigilance in individuals with AgCC using the Connor’s Continuous Performance Test, Second Edition (CPT II) in older adolescents and adults with complete agenesis of the corpus callosum (AgCC) and normal intelligence. Scores were significantly elevated in older adolescents with AgCC for errors of commission and detectability. Older adolescents were worse than adults for commissions and detectability. Also, males had significantly higher (worse) scores than females in Vigilance. These results suggest moderate levels of difficulties in sustained attention in AgCC, particularly in maintaining response inhibition and in vigilance, that are modulated by age and sex.
Paradiso, S., Brown, W.S., Porcerelli, J.H., Tranel, D., Adolphs, R., & Paul, L.K. (in press) “Integration Between Cerebral Hemispheres Contributes to Defense Mechanisms.” Frontiers Psychology.
Integration of information between left and right cerebral hemispheres has been hypothesized to be critical for the development of defense mechanisms.This study tested the role of information integration in the development of defenses. Individuals with agenesis of the corpus callosum (AgCC) and healthy volunteers were compared on defense mechanisms across increasing levels of developmental maturity (Denial, least mature; Projection, intermediate; Identification, most mature) based on response to the Thematic Apperception Test cards (TAT). Compared to controls, participants with AgCC showed significantly greater Denial and less Identification. This finding supports the hypothesis that functional integration across the hemispheres is important for the development of defenses.
Brown, W. S. & Paul, L. K. (2019). The neuropsychological syndrome of agenesis of the corpus callosum. Journal of the International Neuropsychological Society. 1-7. doi: https://doi.org/10.1017/S135561771800111X
This paper describes the core deficits in persons with ACC. The cores syndrome includes: (1) Reduced interhemispheric transfer of sensory-motor information; (2) Reduced cognitive processing speed; and (3) Deficits in complex reasoning and novel problem-solving. As a consequence of these core deficiencies, individuals with ACC have difficulty across various domains of cognitive, behavior, and social functioning.
Young, C.M., Folsom, R.C., Paul, L.K., Su, J., Mangum, R.W., & Brown, W.S. (2019). Awareness of consequences in agenesis of the corpus callosum: semantic analysis of responses. Neuropsychology.
Relative to neurotypical (normal) individuals, persons with ACC scored significantly lower on the Awareness of Consequences Scale, a test of the ability to imagine the consequences of decisions. These results suggest that persons with ACC are deficient in the capacity to imagine the emotional and cognitive consequences to others of their own potential actions, particularly in the face of greater situational and social complexity.
Anderson, L.B., Paul, L.K. & Brown, W.S. (2017). Emotional intelligence in agenesis of the corpus callosum. Arch Clin Neuropsychol. May 1;32(3):267-279. doi:
The Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT) was used to clarify the nature of emotional intelligence in ACC. Persons with ACC exhibited greater disparities from norms on tests involving more complex cognitive processes related to emotions. These findings suggest that the corpus callosum is not necessary for experiencing and thinking about basic emotions, but may be necessary for more complex and second-order cognitive processing regarding emotions, particularly in the context of social interactions.
Paul, L.K., Erickson, R.L., Hartman, J.A. & Brown, W.S. (2016). Learning and memory in individuals with agenesis of the corpus callosum. Neuropsychologia, 86, 183-192. doi: 10.1016/j.neuropsychologia.2016.04.013.
Wechsler Memory Scale was used to test verbal and visual memory in persons with
ACC. Immediate and delayed recall of words and faces were moderately deficient in
ACC. These findings suggest that the corpus callosum facilitates more efficient
learning and recall for both verbal and visual information.
Rehmel, J.L., Brown, W.S., & Paul, L.K. (2016). Proverb comprehension in individuals with agenesis of the corpus callosum. Brain Lang. 160, 21-29. http://dx.doi.org/10.1016/j.bandl.2016.07.001.
Understanding of proverbs in persons with ACC was tested using 2 tests of proverb
interpretation. Persons with ACC performed significantly below neurotypical
(normal) individuals on free-response proverb interpretation but were somewhat
less deficient when given multiple-choice options. The results of this study show that
proverb comprehension is diminished in individuals with ACC.
ADULT COGNITIVE AND PSYCHOSOCIAL DEFICITS FROM
What is hemispherectomy?
Hemispherectomy involves surgical removal of an entire cerebral hemisphere of the brain. This procedure is typically done in children as a last-resort treatment for intractable seizures. “Hemispherectomy” is a term representing a broad category of surgical procedures by disconnecting the cerebral hemispheres.
What are the long-term outcomes of Hemispherectomy?
Despite the fact that this surgical procedure has been used as a treatment for epilepsy in children since the 1980s, there is very little published research on the long-term impact of this treatment on the neuropsychological functioning of these children when they reach adulthood. Thus, there is little information on the long-term outcome of hemispherectomy when seizures are reasonably well controlled by the surgery.
Neuropsychological Research on Hemispherectomy:
For the past several years the HBCL has been studying the long-term neuropsychological and psychosocial functioning of adults who had childhood hemispherectomy. While these studies are still underway, it is clear that what is being discovered will help inform patients, families, and physicians about the outcome of the treatment. There are also important general scientific questions about brain function and intelligence to be investigated by comparing the outcomes of ACC and hemispherectomy.
Krista J. Cowan, Lynn K. Paul, Warren S.Brown “Emotional Functioning in Adults following Childhood Right and Left Hemispherectomy” International Neuropsychological Society, Denver, February, 2020.
Judy J. Su, Mark Graves, Lynn K. Paul, Warren S. Brown. “Using Semantic Similarity to Analyze Strategy Formation in Individuals with Agenesis of the Corpus Callosum.” International Neuropsychological Society, Denver, February, 2020.
Katelyn Mukai, Lynn K. Paul, & Warren S. Brown, “Objective Performance and Self-Report of Executive Functioning Following Childhood Hemispherectomy.” International Neuropsychological Society, Denver, February, 2020.
Krista J. Cowan, Cory E. Kowalski, Kristina Moncrieffe, Amanda Panos, Lynn Paul, & Warren S. Brown, “Emotional Functioning Following Childhood Hemispherectomy.” Meeting of the American Psychological Society, Washington D.C., May 2019.
Mitchell Spezzaferri, Cory E. Kowalski, Kristina Moncrieffe, Amanda Panos, Lynn Paul, & Warren S. Brown, “Social Cognition in Individuals with Hemispherectomy.” Meeting of the American Psychological Society, Washington D.C., May 2019.
Faculty and Principal investigator
Professor of Psychology and Director of Travis Research Institute
BA, POINT LOMA NAZARENE UNIVERSITY
MA, PHD, UNIVERSITY OF SOUTHERN CALIFORNIA
POSTDOCTORAL SCHOLAR, UCLA BRAIN RESEARCH INSTITUTE
Nathan LeFebre. Nate is pursuing a Ph.D. in Clinical Psychology with a neuropsychology track. His research interests include hemispheric differences in social and emotional processing, as well as performance and symptom validity assessment.
Edita Shahnazarian. Edita is pursuing a Ph.D. in Clinical Psychology with a neuropsychology track. Her research interests include the functional impacts of agenesis of the corpus callosum on individuals. She has spent over a year working on several research projects at the University of California, Irvine.
Katie Mukai. Katie is pursuing the Ph.D. in Clinical Psychology, in the neuropsychology track. Her current research is focused on exploring executive function outcomes, particularly cognitive flexibility, in adults who have undergone childhood hemispherectomy to treat intractable seizures. Though not currently conducting research in these areas, she is interested in research regarding posttraumatic growth, adult attachment, interpersonal neurobiology, personality and learning styles, and cognitive recovery following traumatic brain injury.
Krista Cowan, M.A. Krista is pursuing the Ph.D. in Clinical Psychology at Fuller, in the neuropsychology track. Her current research focuses on understanding emotional intelligence and emotional functioning in adults who underwent childhood hemispherectomy due to intractable seizures.
Ashley Vaillancourt, M.A. Ashley is a Ph.D. Candidate in Clinical Psychology. Ashley has been actively researching the psychosocial outcomes of agenesis of the corpus callosum and utilizes these findings as a moderator at the biennial National Organization of Disorders of the Corpus Callosum conference.
Doori Jeong, M.A. Doori is a Ph.D. Candidate in Clinical Psychology, in the Neuropsychology track. Doori has over five years of experience working in the cognitive neuroscience and pathology research lab. She has worked in a rehabilitation hospital and in neuropsychology assessment in private practice. She considers it a privilege to help people better understand themselves in order to maximize their strengths and potentials.
Mitchell Spezzaferri, M.A. Mitchell is pursuing a Ph.D. in Clinical Psychology with a neuropsychology track. He is interested in researching the ways social-cognitive information and emotions are processed in the brain, particularly among individuals who underwent hemispherectomy. He is also investigating moral emotions and moral decision-making strategies.
Matthew Wallace. Matt is pursuing a Psy.D. in Clinical Psychology with a neuropsychology track. Matt's interest within this field involves research on epilepsy, epilepsy surgery, and the impacts of trauma to the brain as a result of epilepsy. His focus is on improving the lives of those who have been impacted by epilepsy.
Matthew Hoard. Matt is pursuing a Ph.D. in Clinical Psychology with a neuropsychology track. His research interests include the functional impacts of agenesis of the corpus callosum on individuals.
Enya Valentin, M.A. Enya is pursuing a Ph.D. in Clinical Psychology with a neuropsychology track. Enya has three years of prior research experience is in applied cognition.
Jasmine Seo Yeong Park. Jasmine is pursuing a Ph.D. in Clinical Psychology with a neuropsychology track. Her current research explores emotion regulation and cognitive reappraisal in adults with agenesis of the corpus callosum.
Paul Figueroa, M.A.
Cory Kowalski. Cory received a Ph.D. in Clinical Psychology. Her research aimed at a better understanding of executive functioning deficits following childhood hemispherectomy.
Kristina Moncrieffe Kristina received a Psy.D. in Clinical Psychology. Her research involved analyzing patterns of intellectual and academic deficits and strengths in adult individuals with hemispherectomies.
Judy Su. Judy received her Ph.D. in Clinical Psychology, in the Neuropsychology track. Her research included the functional impacts of agenesis of the corpus callosum on individuals.
An international consortium of researchers investigating disorders of the corpus callosum, as well as questions more generally related to interconnectivity in the cerebral cortex of humans and animals. Drs. Brown and Paul were founding board members.
An organization focused on understanding and improving the outcomes of hemispherectomy and the surgical treatments of epilepsy. Dr. Monika Jones of this organization has been directly involved in initiating and supporting the research of the HBCL on the outcomes of hemispherectomy.
The primary lab of Dr. Lynn Paul and location for conduction of a part of the research on ACC and hemispherectomy, particularly work involving functional MRI.
The mission of this organization is to support individuals with ACC and their families. Members of the HBCL are significantly involved in the biannual meetings of NODCC. Drs. Brown and Paul were founding board members.