Greg Brown

Testing a place-based theory for environmental evaluation: an Alaska case study

Abstract Norton and Hannon (Environmental Ethics, 19(3), (1997), 227) proposed a theory of environmental evaluation based on a commitment to place or ‘sense of place’ wherein the intensity of environmental valuation is discounted from the home perspective across both time and space – a form of geographic discounting. This theory leads to a series of specific, testable scientific hypotheses relating the physical distance of an object from the point of residence to the intensity of value-judgements. Using community-based survey data collected as part of the planning process in the Chugach National Forest in Alaska (USA), this paper examines the statistical and spatial relationships between ecosystem values and respondent-selected locations on the regional landscape. The findings indicate that ecosystem values are not uniformly distributed across the landscape (not completely spatially random) and that some spatial relationships exist between selected ecosystem values and point of residence (community). The policy implications of these findings for natural resource planning and management are discussed, highlighting the importance of community-based environmental analysis.

Public Participation GIS: A Method for Identifying Ecosystem Services

This study evaluated the use of an Internet-based public participation geographic information system (PPGIS) to identify ecosystem services in Grand County, Colorado. Specific research objectives were to examine the distribution of ecosystem services, identify the characteristics of participants in the study, explore potential relationships between ecosystem services and land use and land cover (LULC) classifications, and assess the methodological strengths and weakness of the PPGIS approach for identifying ecosystem services. Key findings include: (1) Cultural ecosystem service opportunities were easiest to identify while supporting and regulatory services most challenging, (2) participants were highly educated, knowledgeable about nature and science, and have a strong connection to the outdoors, (3) some LULC classifications were logically and spatially associated with ecosystem services, and (4) despite limitations, the PPGIS method demonstrates potential for identifying ecosystem services to augment expert judgment and to inform public or environmental policy decisions regarding land use trade-offs.

Neuropsychological and Information Processing Performance and Its Relationship to White Matter Changes Following Moderate and Severe Traumatic Brain Injury: A Preliminary Study

Reductions in information processing speed have frequently been reported following moderate and severe traumatic brain injuries (TBIs), consistent with the effects of diffuse white matter damage. Although the corpus callosum (CC) is a common site for diffuse damage following TBI, the effects of this damage on information processing speed have not been adequately examined. This study assessed a TBI group and a matched control group on tests of attention, memory, fluency, and set shifting ability, together with reaction time (RT) tasks requiring the inter- and intrahemispheric processing of visual and tactile information. The RT tasks were designed to target the cognitive functions that are likely to be affected by diffuse white matter damage, including damage to the CC. The TBI group demonstrated deficits in verbal and visual fluency and verbal memory. They were also slower on the visual and tactile RT tasks, were more affected by task complexity, and slower on RT tasks requiring the interhemispheric transfer of information. In fact, one of the interhemispheric tactile RT tasks proved to be the most discriminating of all the cognitive and RT measures. MRIs completed on a subset of TBI participants indicated that the mean CC measurements were 5% to 19% smaller than a normative control group, with the most atrophied areas being the isthmus and anterior midbody. Although white matter atrophy was moderately related to visual and tactile RT performance, and total hippocampal volume related to memory performance, CC area was not related to many of the tasks that were designed to tap interhemispheric processing. None of the standard cognitive tests correlated with outcome in the TBI group, but 1 of the tactile RT measures was significantly related to 2 measures of outcome.

An evaluation of internet versus paper-based methods for Public Participation Geographic Information Systems (PPGIS)

Public participation geographic information systems (PPGIS) are an increasingly important tool for collecting spatial information about the social attributes of place. The availability of Internet-based options for implementing PPGIS presents new opportunities for increased efficiency and new modes of access. Here we used a mixed-mode approach to evaluate paper versus Internet mapping methods for the same PPGIS survey in Wyoming. We compared participant characteristics, mapping participation, and the spatial distribution of mapped attributes between participants who responded to the paper versus Internet option. The response rate for those who completed the paper version of the survey was nearly 2.5 times the response rate of the Internet version. Paper participants also mapped significantly more places than did Internet participants (43 vs. 18). Internet participants tended to be younger, more likely to have a college degree, and had lived in the region for less time than paper participants. For all but one attribute there was no difference in the spatial distribution of places mapped between Internet and paper methods. Using a paper-based PPGIS survey resulted in a higher response rate, reduced participant bias, and greater mapping participation. However, survey mode did not influence the spatial distribution of the PPGIS data.

The U.S. forest service: Toward the new resource management paradigm?

Abstract The attitudes and values of U.S. Forest Service employees toward resource management issues are examined by applying general concepts and empirical observations found in the literature on social change and resource sociology. The concept of a resource management paradigm is developed and operationalized in a nationwide study of Forest Service employees. Its results suggest that the attitudes and values of one particular segment of Forest Service employees, the Association of Forest Service Employees for Environmental Ethics (AFSEEE), represent an alternative resource management paradigm that differs significantly from the dominant management paradigm held by the majority of Forest Service employees. The emergence of this extraorganizational group of Forest Service employees dedicated to agency reform is unprecedented in the history of federal land management agencies; their characteristics, both sociodemographic and attitudinal, are compared and contrasted with those of non‐AFSEEE Forest Service ...

Investigating the generators of the scalp recorded visuo-verbal P300 using cortically constrained source localization

Considerable ambiguity exists about the generators of the scalp recorded P300, despite a vast body of research employing a diverse range of methodologies. Previous investigations employing source localization techniques have been limited largely to equivalent current dipole models, with most studies identifying medial temporal and/or hippocampal sources, but providing little information about the contribution of other cortical regions to the generation of the scalp recorded P3. Event‐related potentials (ERPs) were recorded from 5 subjects using a 124‐channel sensor array during the performance of a visuo‐verbal Oddball task. Cortically constrained, MRI‐guided boundary element modeling was used to identify the cortical generators of this target P3 in individual subjects. Cortical generators of the P3 were localized principally to the intraparietal sulcus (IPS) and surrounding superior parietal lobes (SPL) bilaterally in all subjects, though with some variability across subjects. Two subjects also showed activity in the lingual/inferior occipital gyrus and mid‐fusiform gyrus. A group cortical surface was calculated by non‐linear warping of each subjects segmented cortex followed by averaging and creation of a group mesh. Source activity identified across the group reflected the individual subject activations in the IPS and SPL bilaterally and in the lingual/inferior occipital gyrus primarily on the left. Activation of IPS and SPL is interpreted to reflect the role of this region in working memory and related attention processes and visuo‐motor integration. The activity in left lingual/inferior occipital gyrus is taken to reflect activation of regions associated with modality‐specific analysis of visual word forms. Hum. Brain Mapping 18:53–77, 2002.

The average pathlength map: A diffusion MRI tractography-derived index for studying brain pathology

Magnetic resonance diffusion tractography provides a powerful tool for the assessment of white matter architecture in vivo. Quantitative tractography metrics, such as streamline length, have successfully been used in the study of brain pathology. To date, these studies have relied on a priori knowledge of which tracts are affected by injury or pathology and manual delineation of regions of interest (ROIs) for use as waypoints in tractography. This limits the analyses to specific tracts under investigation and relies on the accurate and consistent placement of ROIs. We present a fully automated technique for the voxel-wise analysis of streamline length within the entire brain, the Average Pathlength Map (APM). We highlight the precision and reproducibility of voxel-wise average streamline length over time, and assess normal variability of pathlength values in a cohort of 43 healthy participants. Additionally, we demonstrate the utility of this approach by performing voxel-wise comparison between pathlength values obtained from a patient with a severe traumatic brain injury (TBI, Glasgow Coma Scale Score=7) and those from control participants. Our analysis shows that voxel-wise average pathlength values are comparable to fractional anisotropy (FA) in terms of reproducibility and variability. For the TBI patient, we observed a significant reduction in streamline pathlength in the genu of the corpus callosum and its projections into the frontal lobe. This study demonstrates that the average pathlength map can be used for voxel-based analysis of a quantitative tractography metric within the whole brain, removing both the dependence on a priori knowledge of affected pathways and time-consuming manual delineation of ROIs.

An automated strategy for the delineation and parcellation of commissural pathways suitable for clinical populations utilising high angular resolution diffusion imaging tractography

There is a growing interest in understanding alterations to the interhemispheric transfer of information as a result of brain injury and neurological disease. To facilitate research, we have developed a fully automated method for the accurate extraction of commissural pathways (corpus callosum (CC) and anterior commissure (AC)) and functional parcellation of the CC using a high angular resolution diffusion imaging (HARDI) based probabilistic tractography approach that is applicable to clinical populations. The CC was divided into 33 functional divisions based on its connections to cortical parcellations derived from individual structural images in 8 healthy participants. Probabilistic CC population maps acquired at two different b-values (1000 s mm(-2) and 3000 s mm(-2)) are presented. Topography of the CC was consistent with histology reports. We show that HARDI data acquired at a higher b-value reveals more callosal-temporal connections than low b-value data. With respect to intra-subject precision, data acquired using a higher b-value show superior reproducibility of the delineated CC area on the midsagittal plane (MSP), as well as the total number of callosal streamlines and the number of clustered callosal streamlines. The AC was delineated in all 8 participants using high b-value HARDI tractography. Cortical projections of the AC were analysed and are in agreement with known anatomy. We conclude that, while data acquired at a lower b-value may be used, this is associated with a loss in quality, both in the delineation of commissural pathways and, potentially, the reproducibility of results over time.

Measuring Change in Place Values for Environmental and Natural Resource Planning Using Public Participation GIS (PPGIS): Results and Challenges for Longitudinal Research

Landscape values are a type of place value and are identified and mapped using public participation GIS (PPGIS). PPGIS engages nonexperts to identify important spatial information for environmental or natural resource planning. In 1998, we used PPGIS to identify landscape values for the Chugach National Forest (Alaska) plan revision process. In 2012, we conducted a longitudinal study of the same national forest using Internet PPGIS to identify changes in landscape values. The empirical results indicate stability in landscape values both in importance and spatial distribution. However, the use of different PPGIS methods (paper map vs. Internet) in the longitudinal study also introduced challenges in interpreting and explaining the spatial results. We discuss trade-offs in conducting longitudinal PPGIS research using mixed methods. PPGIS appears well suited for public lands planning, and national forest planning in particular, but barriers to use, such as regulatory approval, remain formidable.

A place-based approach to conservation management using public participation GIS (PPGIS)

The New Zealand Department of Conservation (DOC) is an early adopter of a place-based approach to implementing regional Conservation Management Strategies (CMS). As a new approach, there are few signposts for guidance. The present DOC process relies on a top-down, deductive approach using expert judgement by agency staff. In this study, we examine an alternative approach that uses inductive, public participation GIS (PPGIS) methods to delineate places of significant conservation value. We compare and evaluate the agencys deductive approach with places identified as significant using PPGIS. We discuss the results and present a proposed hierarchy of places framework for use in future place-based conservation management.