Biomedical subjects

Rhonda Douglas Brown

Publications and source records attributed to Rhonda Douglas Brown.

3 recordsLinked to original sources

PubMed2006

Neural correlates of memory development and learning: combining neuroimaging and behavioral measures to understand cognitive and developmental processes.

This special issue includes 4 articles addressing the general theme of neural correlates of memory development and learning. Taken together, the articles represent a broad range of development, including infants, children, adolescents, and adults as participants. Each line of research examines relations between brain activity and cognitive functions using both physiological measures, event-related potentials or functional magnetic resonance imaging, and behavioral measures of memory and learning. This introduction sets the stage by briefly reviewing historical trends in memory development research, discussing major issues associated with neuroimaging research, and providing an integrated perspective of some specific contributions of the investigations included in this special issue, arguing that combining neuroimaging and behavioral measures advances research on memory development and learning in terms of understanding cognitive and developmental processes. The article concludes with a brief discussion of potential future directions for this type of research.

Brain↗

PubMed2006

Making memories: a cross-sectional investigation of episodic memory encoding in childhood using FMRI.

In adults, the neural substrate associated with encoding memories connected to a specific time and place include the prefrontal cortex and medial temporal lobe (MTL). Using functional magnetic resonance imaging, this research studied the developmental trajectory of this frontal-MTL system by comparing 7- and 8-year-old children to those who were 10 or older in conditions that promoted episodic encoding. In 1 condition, participants generated verbs from nouns heard; in another, they listened to short stories for comprehension. Regions in which brain activation predicted subsequent recognition memory performance were identified. These included the left prefrontal cortex, but not MTL, in the verb generation condition for both age groups. In the story comprehension condition, activation in left posterior MTL predicted subsequent memory performance in both age groups, and activation in left anterior MTL (including the hippocampus proper) and left prefrontal cortex predicted subsequent memory only for the older children. These results illustrate both similarities and differences in how brain systems interact in development to mediate the formation of episodic memories.

Adolescent↗

PubMed2004

Empirical validation of the triple-code model of numerical processing for complex math operations using functional MRI and group Independent Component Analysis of the mental addition and subtraction of fractions.

The suitability of a previously hypothesized triple-code model of numerical processing, involving analog magnitude, auditory verbal, and visual Arabic codes of representation, was investigated for the complex mathematical task of the mental addition and subtraction of fractions. Functional magnetic resonance imaging (fMRI) data from 15 normal adult subjects were processed using exploratory group Independent Component Analysis (ICA). Separate task-related components were found with activation in bilateral inferior parietal, left perisylvian, and ventral occipitotemporal areas. These results support the hypothesized triple-code model corresponding to the activated regions found in the individual components and indicate that the triple-code model may be a suitable framework for analyzing the neuropsychological bases of the performance of complex mathematical tasks.

Adult↗