Our lab studies the neural bases of reading and language. We use "brainwave" technologies (EEG and ERP) to study how the brain responds during various cognitive and linguistic manipulations, such as comprehending language that is familiar (e.g., well-known words) versus language that is new or recently learned (e.g., very rare words or new grammatical constructions). Anatomical source modeling is used to estimate the locations of brainwave generators, in order to create spatiotemporal models of neural activity. Our studies include children (ages 8–14), as well younger and older adults.
Work at the BIRC laboratory encompasses collaborative work of Bruce Crosson, PhD, Joe Nocera, PhD, and Keith McGregor, PhD. The focus of our laboratory is in understanding the neural substrates of cognition and motor control and how to mitigate changes in these functions related to aging, disease, and injury. The main tools currently used to study brain function in the BIRC laboratory are functional MRI and transcranial magnetic stimulation. The research group at the BIRC laboratory also has the tools and expertise to measure aerobic fitness. Recent and current studies include: (1) use of a cognitive-behavioral intervention to remap language functions during aphasia therapy; (2) aging-related changes in the neural substrates of word finding and in mobility and their response to exercise; (3) aging-related changes in motor control and their response to exercise; (4) neural and cognitive substrates of word-finding impairment in Alzheimer’s disease and amnestic mild cognitive impairment; (5) whether increased right frontal activity helps or hinders word retrieval in older persons; and (6) whether aging-related cognitive and behavioral changes share common neural substrates. Most of this work takes place in the Center for Visual and Neurocognitive Rehabilitation (CVNR) at the Atlanta VA Medical Center, and work of the BIRC laboratory overlaps with the Neuroimaging Core of the CVNR, where young investigators are trained to do neuroimaging.
Our labs share the goal of investigating cognitive and emotional functions in humans using several methodologies including functional neuroimaging, psychophysiology, experimental cognitive tasks, and traditional clinical neuropsychological assessment measures. We have interests in learning more about the biological, psychological and social-environmental processes underlying developmental disorders and acquired neurological conditions across the lifespan. Therefore we are committed to clinical research in the field of developmental neuropsychology. Our goals are to advance our understanding of brain-behavior relationships, and to further the development of empirically validated classification criteria, reliable and valid assessment measures and effective intervention strategies for these clinical populations. The majority of our projects are collaborative efforts.
The following projects are ongoing in our labs:
For more information, please see our individual faculty web pages.
This laboratory studies behavioral changes that occur in response to exposure to psychological stress. We hope to delineate brain mechanisms that underlie these changes and to suggest ways in which maladaptive changes might be blocked or reversed. We use multiple levels of analysis from behavioral to molecular in order to answer these questions. The laboratory uses computerized behavioral analysis systems (Noldus Observer and Ethovision), stereotaxic surgery and intracranial microinjections, as well as immunohistochemistry, in situ hybridization, and viral vector gene transfer.
Our laboratory is interested in understanding the neural substrates of social behavior, in particular mechanisms underlying sexual attraction and individual recognition. We are also seek to define how, at a neural systems level, sex differences in sexual attraction are encoded. We use chemical or "pheromonal" communication in the golden hamster as our model for understanding these social recognition processes. The laboratory uses state-of-the-art electrophysiological techniques to record single neuron and ensemble activity in animals while they investigate social odors. In addition, behavioral, lesion, immunocytochemical and central injection methods are also used as a means of understanding the function of limbic area structures (amygdala, hypothalamus, hippocampus) in the regulation of adaptive social recognition.
The Laboratory of Neuroendocrinology and Behavior investigates the neural mechanisms that regulate circadian rhythms as well as the neural circuits that control social behaviors. The laboratory is well equipped with facilities that allow studies that range from the level of gene expression to behavior.
Research in my laboratory is in the area of neuroethology, the study of the neural basis of natural behavior. We focus on the neural and endocrine systems underlying animal communication and the role of communication signals in aggressive interactions and reproductive behavior. Using amphibians and reptiles as model systems, we use a multidisciplinary approach to investigating how communication signals, behavioral responses, and hormonal state are monitored and controlled by neural systems, and how in turn these neural systems are modified by social experience and the hormonal changes such experience triggers. Research projects in the lab often employ combinations of neuroanatomical, neuroendocrinological, neurophysiological, or behavioral techniques to gain a more complete understanding of the neural mechanisms underlying social behavior and its evolution.
This laboratory has state-of-the-art equipment for measuring hormones related to energy balance and reproductive status and for in vitro measurement of fat-cell metabolism and related metabolic events. It also has a high-pressure liquid chromatography system for measurement of neurotransmitters, microscopy and histology equipment for measurement of immunocytochemical peptide staining in the brain, a computer-controlled system for measuring 24h locomotor activity and oxygen consumption, and a system that permits either systemic or central infusions of hormones, peptides or pharmacological agents in freely-moving animals. Equipment for standard molecular biology assays also is present. We also specialize in the use of viral trans-synaptic tract tracers for defining complete circuits within an animal. Finally, a complete neurohistology facility within the lab exists for fluorescence, dark field, standard light microscopy, as well as equipment for in situ hybridization of gene expression for neuropeptides of interest. Thus, the levels of analysis include dddd\\behavioral,systems physiology, cell physiology and anatomy, neuroanatomy and molecular biology.
This laboratory combines a variety of neuropharmacological methods, including systemic and intracranial drug infusions, in vivo microdialysis, permanent and reversible lesions, and immunocytochemistry to investigate the brain systems and neurochemical processes that contribute to memory and memory dysfunction. The laboratory has a well-equipped surgical suite, which includes as a system capable of delivering anesthesia to four stereotaxes simultaneously, as well a mobile anesthesia system. There are also several apparatuses to assess learning, memory, and anxiety and a computerized behavioral analysis system (Ethovision). The lab is also equipped to perform in vivo microdialysis procedures during behavioral tests of learning and memory. A microplate reader is available to measure a variety of substances present in blood and brain samples and the laboratory is also outfitted with histological and immunocytochemical equipment to allow for visualization of brain tissue.
The SCLSL is a component of the Language Research Center, and provides facilities and apparatus for the study of cognitive processes across primate species. Humans, rhesus monkeys, and chimpanzees (with and without language training) can be tested on computerized versions of many standard assessment tasks from cognitive neuroscience. Apparatus for transcranial magnetic stimulation (TMS) and transcranial doppler sonography are also available for investigating functional cerebral asymmetries and other aspects of localization of cognitive function. Eye trackers / pupillometers (ISCAN, Inc.) are also available both on campus and at the SCLSL to allow investigators to relate variations these psychophysiological measures to cognitive performance.