Distribution modeling of Rafflesia schadenbergiana and Rafflesia consueloea using multi criteria decision analysis-analytical hierarchy process in GIS

The identification of potential habitats of the largest and smallest flowering parasitic Rafflesia in the Philippines is a prerequisite in conservation of species and preservation of their habitats which have been being degraded due to anthropogenic activities and climate change. This research aimed at revealing the possible habitat suitability for Rafflesia schadenbergiana Göppert ex Hieron and Rafflesia consueloae Galindon, Ong Fernando throughout the Philippines using Geographic Information Systems (GIS). The selection criteria in this research were based on four parameters (elevation, annual rainfall, temperature, and land use / land classification) identified during the extensive literature review. The generated map shows that the optimal growth of the Rafflesia schadenbergiana can be observed with a temperature range of 20–22°C while Rafflesia consueloae can thrive within 24°C to 25°C. The importance of these criteria was evaluated using a pairwise comparison method and the final weight was computed for each criterion. Setting up of the values suiting the subject species was followed by weighted overlay analysis. The final output is the distribution and habitat suitability of the subject species.

The role of metamemory in autobiographical memory performance in dysphoric individuals

Autobiographical memory (AM) performance in individuals with depressive symptoms has repeatedly been shown to be overgeneral (OGM) in nature, and characterized by summaries of repeated events or long periods of time rather than a single event tied to a unique spatial and temporal context. The present body of work was designed to address the metamnemonic aspects of AM performance in dysphoric individuals, with the underlying motivation being that OGM may not be a unique phenomenon specific to depression or AM, and that it may reflect a more general pattern of memory impairment. The studies presented herein examine various aspects of metamemory and other memory processes that may offer a parsimonious account of OGM as poor event memory in general, rather than a specific standalone finding. In Study 1 several metamnemonic processes were investigated using a quantity-accuracy profile approach. Here, the results showed that performance between dysphoric and non-dysphoric participants was nearly indistinguishable on measures of calibration, resolution, grain-size setting, and criterion setting, suggesting that these aspects of metamemory are intact in dysphoria for immediately tested material. Study 2 examined whether it is possible to “create” OGMs by employing a delay manipulation for both autobiographical (3 day delay) and laboratory-based events (7 day delay). Indeed, the results from this study showed that the performance on both tasks declines for both groups, but that this effect was of a greater magnitude in the dysphoric group. Critically, no differences emerged for immediately tested information. Finally, Study 3 examined the role of working memory and memory search strategies in the recollection of autobiographically relevant information. The results from Study 3 showed that dysphoric individuals may engage in a less organized search strategy than non-dysphoric participants as exhibited by a tendency to switch set in the midst of thematically related information. Taken as a whole, these data indicate that OGM may be attributable to deficits in memory search strategies in conjunction with memories that may be more prone to decay and/or forgetting, suggesting that OGM may not be a depression-specific phenomenon, but rather the downstream deficit of degraded memory representation.

The role of metamemory in autobiographical memory performance in dysphoric individuals

Autobiographical memory (AM) performance in individuals with depressive symptoms has repeatedly been shown to be overgeneral (OGM) in nature, and characterized by summaries of repeated events or long periods of time rather than a single event tied to a unique spatial and temporal context. The present body of work was designed to address the metamnemonic aspects of AM performance in dysphoric individuals, with the underlying motivation being that OGM may not be a unique phenomenon specific to depression or AM, and that it may reflect a more general pattern of memory impairment. The studies presented herein examine various aspects of metamemory and other memory processes that may offer a parsimonious account of OGM as poor event memory in general, rather than a specific standalone finding. In Study 1 several metamnemonic processes were investigated using a quantity-accuracy profile approach. Here, the results showed that performance between dysphoric and non-dysphoric participants was nearly indistinguishable on measures of calibration, resolution, grain-size setting, and criterion setting, suggesting that these aspects of metamemory are intact in dysphoria for immediately tested material. Study 2 examined whether it is possible to “create” OGMs by employing a delay manipulation for both autobiographical (3 day delay) and laboratory-based events (7 day delay). Indeed, the results from this study showed that the performance on both tasks declines for both groups, but that this effect was of a greater magnitude in the dysphoric group. Critically, no differences emerged for immediately tested information. Finally, Study 3 examined the role of working memory and memory search strategies in the recollection of autobiographically relevant information. The results from Study 3 showed that dysphoric individuals may engage in a less organized search strategy than non-dysphoric participants as exhibited by a tendency to switch set in the midst of thematically related information. Taken as a whole, these data indicate that OGM may be attributable to deficits in memory search strategies in conjunction with memories that may be more prone to decay and/or forgetting, suggesting that OGM may not be a depression-specific phenomenon, but rather the downstream deficit of degraded memory representation.

Are visual working memory and episodic memory distinct processes? Insight from stroke patients by lesion-symptom mapping

Working memory and episodic memory are two different processes, although the nature of their interrelationship is debated. As these processes are predominantly studied in isolation, it is unclear whether they crucially rely on different neural substrates. To obtain more insight in this, 81 adults with sub-acute ischemic stroke and 29 elderly controls were assessed on a visual working memory task, followed by a surprise subsequent memory test for the same stimuli. Multivariate, atlas- and track-based lesion-symptom mapping (LSM) analyses were performed to identify anatomical correlates of visual memory. Behavioral results gave moderate evidence for independence between discriminability in working memory and subsequent memory, and strong evidence for a correlation in response bias on the two tasks in stroke patients. LSM analyses suggested there might be independent regions associated with working memory and episodic memory. Lesions in the right arcuate fasciculus were more strongly associated with discriminability in working memory than in subsequent memory, while lesions in the frontal operculum in the right hemisphere were more strongly associated with criterion setting in subsequent memory. These findings support the view that some processes involved in working memory and episodic memory rely on separate mechanisms, while acknowledging that there might also be shared processes.

Are visual working memory and episodic memory distinct processes? Insight from stroke patients by lesion-symptom mapping.

Working memory and episodic memory are two different processes, although the nature of their interrelationship is debated. As these processes are predominantly studied in isolation, it is unclear whether they crucially rely on different neural substrates. To obtain more insight in this, eighty-one adults with sub-acute ischemic stroke and twenty-nine elderly controls were assessed on a visual working memory task, followed by a surprise subsequent memory test for the same stimuli. Multivariate, atlas- and track-based lesion-symptom mapping (LSM) analyses were performed to identify anatomical correlates of visual memory. Behavioral results gave moderate evidence for independence between discriminability in working memory and subsequent memory, and strong evidence for a correlation in response bias on the two tasks in stroke patients. LSM analyses suggested there might be independent regions associated with working memory and episodic memory. Lesions in the right arcuate fasciculus were more strongly associated with discriminability in working memory than in subsequent memory, while lesions in the frontal operculum in the right hemisphere were more strongly associated with criterion setting in subsequent memory. These findings support the view that some processes involved in working memory and episodic memory rely on separate mechanisms, while acknowledging that there might also be shared processes.

The Quest for Hemispheric Asymmetries Supporting and Predicting Executive Functioning

This narrative review addresses the neural bases of two executive functions: criterion setting, that is, the capacity to flexibly set up and select task rules and associations between stimuli, responses, and nonresponses, and monitoring, that is, the process of continuously evaluating whether task rules are being applied optimally. There is a documented tendency for criterion setting and monitoring to differentially recruit left and right lateral prefrontal regions and connected networks, respectively, above and beyond the specific task context. This model, known as the ROtman–Baycrest Battery to Investigate Attention model, initially sprung from extensive neuropsychological work leaded by Don Stuss. In subsequent years, multimodal lines of empirical investigation on both healthy individuals and individuals with brain damage, coming from functional neuroimaging, EEG, neurostimulation, individual difference approaches, and, again, neuropsychology, so to “complete the circle,” corroborated the functional mapping across the two hemispheres as predicted by the model. More recent electrophysiological evidence has further shown that hemispheric differences in intrinsic prefrontal dynamics are able to predict cognitive performance in tasks tapping these domain-general functions. These empirical contributions will be presented together with contrasting evidence, limits, and possible future directions to better fine-tune this model and extend its scope to new fields.

The role of decision criterion in the Deese–Roediger–McDermott (DRM) false recognition memory: False memory falls and rises as a function of restriction on criterion setting

How much of the Deese–Roediger–McDermott (DRM) false memory is attributable to decision criterion is so far a controversial issue. Previous studies typically used explicit warnings against accepting the critical lure to investigate this issue. The assumption is that if the false memory results from using a liberally biased criterion, it should be greatly reduced or eliminated by an explicit warning against accepting the critical lure. Results showed that warning was generally ineffective. We asked the question of whether subjects can substantially reduce false recognition without being warned when the test forces them to make a distinction between true and false memories. Using a two-alternative forced choice in which criterion plays a relatively smaller role, we showed that subjects could indeed greatly reduce the rate of false recognition. However, when the forced-choice restriction was removed from the two-item choice test, the rate of false recognition rebounded to that of the hit for studied list words, indicating the role of criterion in false recognition.