Publications by authors named "Christopher Cannistraci"

Dramatic advances in the management of congenital heart disease (CHD) have improved survival to adulthood from less than 10% in the 1960s to over 90% in the current era, such that adult CHD (ACHD) patients now outnumber their pediatric counterparts. ACHD patients demonstrate domain-specific neurocognitive deficits associated with reduced quality of life that include deficits in educational attainment and social interaction. Our hypothesis is that ACHD patients exhibit vascular brain injury and structural/physiological brain alterations that are predictive of specific neurocognitive deficits modified by behavioral and environmental enrichment proxies of cognitive reserve (e.

View Article and Find Full Text PDF

The purpose of this study was to determine associations among neurocognitive outcomes and white matter integrity in the inferior fronto-occipital fasciculus (IFOF), uncinate fasciculus (UF), and genu of the corpus callosum (gCC) in survivors of pediatric brain tumor and healthy controls (HCs). Eleven survivors (ages 8-16; >2 years post-treatment) and 14 HCs underwent MRI; diffusion tensor imaging tractography (DSI Studio) was used to assess white matter integrity. Participants completed neuropsychological assessment of overall cognitive ability, executive function, processing speed, divided attention, and memory.

View Article and Find Full Text PDF

Purpose: After treatment, pediatric brain tumor survivors (PBTS) face emotional and behavioral challenges, perhaps due to tumor or treatment-related changes in brain structures involved in emotion regulation, including those with fronto-limbic connections. We hypothesized that relative to healthy controls (HCs), PBTS would exhibit greater difficulties with behavior and emotional functioning, and display reduced mean fractional anisotropy (mFA) in white matter tracts with fronto-limbic connections including the cingulum bundle (CB), inferior fronto-occipital fasciculus (IFOF), and uncinate fasciculus (UF). We further predicted that mFA would account for variance in the relationship between group and emotional/behavioral outcome.

View Article and Find Full Text PDF

Introduction: Psychotic spectrum disorder (PSD) links the syndromes of bipolar disorder, psychotic depression, and schizophrenia, often viewed as unique disorders.

Aims: Application of the PSD concept to a single patient rather than across groups of patients and demonstration of a remarkable remission of schizophrenia phenotype with recovery of gray matter in specific brain regions.

Results: We report a woman who experienced discrete, nonoverlapping periods of each of the above syndromes, in the order noted, over a 30-year period, followed by abrupt ending of psychosis and full remission lasting at least 7 years.

View Article and Find Full Text PDF

Purpose: We undertook this pilot prospective cohort investigation to examine the feasibility of functional magnetic resonance imaging (fMRI) assessments in survivors of critical illness and to analyze potential associations between delirium and brain activation patterns observed during a working memory task (N-back) at hospital discharge and 3-month follow-up.

Materials And Methods: At hospital discharge and 3 months later, fMRI assessed subjects' functional activity during an N-back task. Multiple linear regression was used to examine associations between duration of delirium and brain activity, and elastic net regression was used to assess the relationship between brain activation patterns at 3 months and cognitive outcomes at 12 months.

View Article and Find Full Text PDF

Purpose: Pediatric brain tumors are the second most common cancer diagnosis in individuals under age 20 and research has documented significant neurocognitive, psychosocial, and emotional late effects. Associations among these deficits have not been adequately considered and the role of survivors' coping with stress in relation to deficits is unknown. Further, research has yet to examine neurobiological processes related to neurocognitive, psychosocial, and emotional difficulties in survivors through the use of functional neuroimaging.

View Article and Find Full Text PDF

Objective: Research on the long-term sequelae of treatment for pediatric brain tumors has identified significant neurocognitive deficits experienced by many survivors. Despite indications of deficits based on cognitive assessment, the identification of specific neurobiological mechanisms of these deficits using neuroimaging techniques has yet to be considered.

Method: This study used norm-referenced standardized assessment and functional MRI (fMRI) to examine attention and executive functioning deficits of survivors of pediatric brain tumors, as compared with healthy children.

View Article and Find Full Text PDF

A network of brain regions involving the ventral inferior frontal gyrus/anterior insula (vIFG/AI), presupplementary motor area (pre-SMA) and basal ganglia has been implicated in stopping impulsive, unwanted responses. However, whether this network plays an equal role in response inhibition under different sensorimotor contexts has not been tested systematically. Here, we conducted an fMRI experiment using the stop signal task, a sensorimotor task requiring occasional withholding of the planned response upon the presentation of a stop signal.

View Article and Find Full Text PDF

Objective: Delirium duration is predictive of long-term cognitive impairment in intensive care unit survivors. Hypothesizing that a neuroanatomical basis may exist for the relationship between delirium and long-term cognitive impairment, we conducted this exploratory investigation of the associations between delirium duration, brain volumes, and long-term cognitive impairment.

Design, Setting, And Patients: A prospective cohort of medical and surgical intensive care unit survivors with respiratory failure or shock.

View Article and Find Full Text PDF

Objective: Evidence is emerging that delirium duration is a predictor of long-term cognitive impairment in intensive care unit survivors. Relationships between 1) delirium duration and brain white matter integrity, and 2) white matter integrity and long-term cognitive impairment are poorly understood and could be explored using magnetic resonance imaging.

Design, Setting, Patients: A two-center, prospective cohort study incorporating delirium monitoring, neuroimaging, and cognitive testing in intensive care unit survivors.

View Article and Find Full Text PDF

The serotonergic neurotoxin, 3,4-methylenedioxymethamphetamine (MDMA/Ecstasy), is a highly popular recreational drug. Human recreational MDMA users have neurocognitive and neuropsychiatric impairments, and human neuroimaging data are consistent with animal reports of serotonin neurotoxicity. However, functional neuroimaging studies have not found consistent effects of MDMA on brain neurophysiology in human users.

View Article and Find Full Text PDF

Objective: Heightened amygdala reactivity to aversive stimuli in major depression is regarded as a core feature of the underlying physiology but individual differences in amygdala response may also arise secondary to persistent changes in limbic function during early neurodevelopment relative to stressors such as childhood trauma. We sought to determine whether heightened amygdala response is a core feature of depression or a general risk factor for psychopathology secondary to early life stress.

Method: Twenty unipolar depressed patients with and without a history of significant early life trauma and 16 healthy comparison subjects underwent functional MRI in a cross-sectional study comparing neural response to sad and neutral faces.

View Article and Find Full Text PDF

Background: Number processing deficits are frequently seen in children exposed to alcohol in utero.

Methods: Functional magnetic resonance imaging was used to examine the neural correlates of number processing in 15 right-handed, 8- to 12-year-old children diagnosed with fetal alcohol syndrome (FAS) or partial FAS (PFAS) and 18 right-handed, age- and gender-matched controls from the Cape Coloured (mixed ancestry) community in Cape Town, South Africa, using Proximity Judgment and Exact Addition tasks.

Results: Control children activated the expected fronto-parietal network during both tasks, including the anterior horizontal intraparietal sulcus (HIPS), left posterior HIPS, left precentral sulcus, and posterior medial frontal cortex.

View Article and Find Full Text PDF

Williams syndrome is a genetic neurodevelopmental disorder with a distinctive phenotype, including cognitive-linguistic features, nonsocial anxiety, and a strong attraction to music. we preformed functional MRI studies examining brain responses to musical and other types of stimuli in young adults with Williams syndrome and typically developing controls. In Study 1, the Williams syndrome group exhibited unforeseen activations of the visual cortex to musical stimuli, and it was this novel finding that became the focus of two subsequent studies.

View Article and Find Full Text PDF

By contrast to the adult literature, in which a consistent parietofrontal network for number processing has been identified, the data from studies of number processing in children have been less consistent, probably due to differences in study design and control conditions. Number processing was examined using functional magnetic resonance imaging in 18 right-handed children (8-12 years) from the Cape Coloured community in Cape Town, South Africa, using Proximity Judgment and Exact Addition (EA) tasks. The findings were consistent with the hypothesis that, as in adults, the anterior horizontal intraparietal sulcus (HIPS) plays a major role in the representation and manipulation of quantity in children.

View Article and Find Full Text PDF

Background: Research on the physical and psychological late effects of treatment of childhood cancer has led to the identification of significant long-term neurocognitive deficits experienced by some survivors, particularly in the areas of memory and executive functioning. Despite indications of deficits based on cognitive assessment, the identification of specific mechanisms of neurocognitive deficits using neuroimaging techniques has yet to be adequately considered.

Procedure: This study used functional neuroimaging techniques to examine working memory and executive functioning deficits of survivors of childhood acute lymphocytic leukemia (ALL), as compared to age- and gender-matched healthy controls.

View Article and Find Full Text PDF

Most studies investigating mental numerical processing involve adult participants and little is known about the functioning of these systems in children. The current study used functional magnetic resonance imaging (fMRI) to investigate the neural correlates of numeracy and the influence of age on these correlates with a group of adults and a group of third graders who had average to above average mathematical ability. Participants performed simple and complex versions of exact and approximate calculation tasks while in the magnet.

View Article and Find Full Text PDF

We used functional magnetic resonance imaging (fMRI) to explore the patterns of brain activation associated with different levels of performance in exact and approximate calculation tasks in well-defined cohorts of children with mathematical calculation difficulties (MD) and typically developing controls. Both groups of children activated the same network of brain regions; however, children in the MD group had significantly increased activation in parietal, frontal, and cingulate cortices during both calculation tasks. A majority of the differences occurred in anatomical brain regions associated with cognitive resources such as executive functioning and working memory that are known to support higher level arithmetic skill but are not specific to mathematical processing.

View Article and Find Full Text PDF

Different methods of assessing human brain function possess specific advantages and disadvantages compared to others, but it is believed that combining different approaches will provide greater information than can be obtained from each alone. For example, functional magnetic resonance imaging (fMRI) has good spatial resolution but poor temporal resolution, whereas the converse is true for electrophysiological recordings (event-related potentials or ERPs). In this review of recent work, we highlight a novel approach to combining these modalities in a manner designed to increase information on the origins and locations of the generators of specific ERPs and the relationship between fMRI and ERP signals.

View Article and Find Full Text PDF

Quantitative characterization of multiple sclerosis (MS) lesion load is of considerable interest to clinical follow-up studies. Based on fuzzy clustering of multiparameter magnetic resonance images, we have developed a computer-assisted system for volumetric quantification of brain tissue. Tests on patient data show that the system is very efficient, and volumetric measurements characterized are highly reproducible.

View Article and Find Full Text PDF

Recent brain imaging and lesion studies provide converging evidence for amygdala involvement in judgments of fear and trust based on facial expression [Adolphs et al., Nature 393 (1998) 470; Adolphs et al., Neuropsychologia 37 (1999) 1111; Breiter et al.

View Article and Find Full Text PDF