94 research outputs found
The Architect Who Lost the Ability to Imagine: The Cerebral Basis of Visual Imagery.
While the loss of mental imagery following brain lesions was first described more than a century ago, the key cerebral areas involved remain elusive. Here we report neuropsychological data from an architect (PL518) who lost his ability for visual imagery following a bilateral posterior cerebral artery (PCA) stroke. We compare his profile to three other patients with bilateral PCA stroke and another architect with a large PCA lesion confined to the right hemisphere. We also compare structural images of their lesions, aiming to delineate cerebral areas selectively lesioned in acquired aphantasia. When comparing the neuropsychological profile and structural magnetic resonance imaging (MRI) for the aphantasic architect PL518 to patients with either a comparable background (an architect) or bilateral PCA lesions, we find: (1) there is a large overlap of cognitive deficits between patients, with the very notable exception of aphantasia which only occurs in PL518, and (2) there is large overlap of the patients' lesions. The only areas of selective lesion in PL518 is a small patch in the left fusiform gyrus as well as part of the right lingual gyrus. We suggest that these areas, and perhaps in particular the region in the left fusiform gyrus, play an important role in the cerebral network involved in visual imagery
The Adaptability of Full Cast Crown in Preclinical Practice
A study was made to evaluate the adaptability of full cast crowns in preclinical practice of the fifth year students at Matsumoto Dental College in 1984. Gap space between the inner surface of the full cast crown and the surface of the abutment tooth was investigated with silicon material. The results were as follows: 1) The adaptability of crowns was better at the mesial surface than at the distal surface, and better at the lingual surface than at the buccal surface. 2) The adaptability of crowns was better at the axial walls, especialy in the middle, than in the cervical margin. 3) At the occulusal surface, the adaptability of crowns was worst
What do people with aphasia want to be able to say? A content analysis of words identified as personally relevant by people with aphasia
Background
Word finding is a common difficulty for people with aphasia. Targeting words that are relevant
to the individual could maximise the usefulness and impact of word finding therapy.
Aims
To provide insights into words that people with aphasia perceive to be personally relevant.
Methods and procedures
100 people with aphasia were each asked to identify 100 words that would be particularly
important for them to be able to say. Two speech and language therapist researchers conducted
a quantitative content analysis of the words selected. The words were coded into a
framework of topics and subtopics. The frequency with which different words and topics
were selected was then calculated.
Outcomes and results
100 participants representing 20 areas of the United Kingdom ranged in age from 23 to 85
years. Word finding difficulties ranged from mild to severe. The sample of 9999 words
selected for practice included 3095 different words in 27 topics. The majority of words
selected (79.4%) were from the topics ‘food and drink’ (30.6%), ‘nature and gardening’
(10.3%), ‘entertainment’ (9.4%), ‘places’ (7.3%), ‘people’ (6.7%), ‘house’ (6.5%), ‘clothes’
(5.2%) and ‘travel’ (3.5%). The 100 words types chosen with the greatest frequency were
identified. These account for 27 percent of the 9999 words chosen by the participants.
Discussion
Personally relevant vocabulary is unique to each individual and is likely to contain specific or
specialist words for which material needs to be individually prepared. However there is
some commonality in the words chosen by people with aphasia. This could inform pre-prepared materials for use in word finding therapy from which personally relevant words
could be selected for practice
Measurement theory and paleobiology
Measurement theory, a branch of applied mathematics, offers guiding principles for extracting meaning from empirical observations and is applicable to any science involving measurements. Measurement theory is highly relevant in paleobiology because statistical approaches assuming ratio-scaled variables are commonly used on data belonging to nominal and ordinal scale types. We provide an informal introduction to representational measurement theory and argue for its importance in robust scientific inquiry. Although measurement theory is widely applicable in paleobiology research, we use the study of disparity to illustrate measurement theoretical challenges in the quantitative study of the fossil record. Respecting the inherent properties of different measurements enables meaningful inferences about evolutionary and ecological processes from paleontological data
Altruism in a volatile world
This is the author accepted manuscript. The final version is available from Springer Nature via the DOI in this record.The evolution of altruism – costly self-sacrifice in the service of others – has puzzled biologists since
The Origin of Species. For half a century, attempts to understand altruism have been built on the insight
that altruists may help relatives to have extra offspring in order to spread shared genes . This theory –
known as inclusive fitness – is founded on a simple inequality termed ‘Hamilton’s rule’. However, explanations of altruism have typically ignored the stochasticity of natural environments, which will not
necessarily favour genotypes that produce the greatest average reproductive success. Moreover,
empirical data across many taxa reveal associations between altruism and environmental stochasticity, a pattern not predicted by standard interpretations of Hamilton’s rule. Here, we derive Hamilton’s rule
with explicit stochasticity, leading to novel predictions about the evolution of altruism. We show that of offspring produced by relatives. Consequently, costly altruism can evolve even if it has a net negative
effect on the average reproductive success of related recipients. The selective pressure on volatility
suppressing altruism is proportional to the coefficient of variation in population fitness, and is therefore diminished by its own success. Our results formalise the hitherto elusive link between bet-hedging and
altruism, and reveal missing fitness effects in the evolution of animal societies.PK was supported by the National Geographic Society (GEF-NE 145-15) and a
University of Bristol Research Studentship; ADH was supported by the Natural Environment Research
Council (NE/L011921/1); ANR was supported by a European Research Council Consolidator Grant
(award no. 682253); and SS was supported by the Natural Environment Research Council
(NE/M012913/2)
Investigating Unique Environmental Contributions to the Neural Representation of Written Words: A Monozygotic Twin Study
The visual word form area (VWFA) is a region of left inferior occipitotemporal cortex that is critically involved in visual word recognition. Previous studies have investigated whether and how experience shapes the functional characteristics of VWFA by comparing neural response magnitude in response to words and nonwords. Conflicting results have been obtained, however, perhaps because response magnitude can be influenced by other factors such as attention. In this study, we measured neural activity in monozygotic twins, using functional magnetic resonance imaging. This allowed us to quantify differences in unique environmental contributions to neural activation evoked by words, pseudowords, consonant strings, and false fonts in the VWFA and striate cortex. The results demonstrate significantly greater effects of unique environment in the word and pseudoword conditions compared to the consonant string and false font conditions both in VWFA and in left striate cortex. These findings provide direct evidence for environmental contributions to the neural architecture for reading, and suggest that learning phonology and/or orthographic patterns plays the biggest role in shaping that architecture
The hierarchy-of-hypotheses approach: A synthesis method for enhancing theory development in ecology and evolution
13 páginas.- 4 figuras.- referencias.- Supplemental material is available at BIOSCI online. https://doi.org/10.1093/biosci/biaa130In the current era of Big Data, existing synthesis tools such as formal meta-analyses are critical means to handle the deluge of information. However, there is a need for complementary tools that help to (a) organize evidence, (b) organize theory, and (c) closely connect evidence to theory. We present the hierarchy-of-hypotheses (HoH) approach to address these issues. In an HoH, hypotheses are conceptually and visually structured in a hierarchically nested way where the lower branches can be directly connected to empirical results. Used for organizing evidence, this tool allows researchers to conceptually connect empirical results derived through diverse approaches and to reveal under which circumstances hypotheses are applicable. Used for organizing theory, it allows researchers to uncover mechanistic components of hypotheses and previously neglected conceptual connections. In the present article, we offer guidance on how to build an HoH, provide examples from population and evolutionary biology and propose terminological clarifications.The workshops were funded by Volkswagen Foundation (Az 92,807 and 94,246). TH, CAA, ME, PG, ADS, and JMJ received funding from German Federal Ministry of Education and Research within the Collaborative Project “Bridging in Biodiversity Science” (grant no. 01LC1501A). ME additionally received funding from the Foundation of German Business, JMJ from the Deutsche Forschungsgemeinschaft (grants no. JE 288/9–1 and JE 288/9–2), and IB from German Federal Ministry of Education and Research (grant no. FKZ 01GP1710). CJL was supported by a grant from The Natural Sciences and Engineering Research Council of Canada and in-kind synthesis support from the US National Center for Ecological Analysis and Synthesis. LGA was supported by the Spanish Ministry of Science, Innovation, and Universities through project no. CGL2014–56,739-R, and RRB received funding from the Brazilian National Council for Scientific and Technological Development (process no. 152,289/2018–6)Peer reviewe
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