Search results for "Lobe"

2021

Abstract Pantomime has a long tradition in clinical neuropsychology of apraxia. It has been much more used by researchers and clinicians to assess tool-use disorders than real tool use. Nevertheless, it remains incompletely understood and has given rise to controversies, such as the involvement of the left inferior parietal lobe or the nature of the underlying cognitive processes. The present article offers a comprehensive framework, with the aim of specifying the neural and cognitive bases of pantomime. To do so, we conducted a series of meta-analyses of brain-lesion, neuroimaging, and behavioral studies about pantomime and other related tasks (i.e., real tool use, imitation of meaningless…

Technition: When Tools Come Out of the Closet

2020

People are ambivalently enthusiastic and anxious about how far technology can go. Therefore, understanding the neurocognitive bases of the human technical mind should be a major topic of the cognitive sciences. Surprisingly, however, scientists are not interested in this topic or address it only marginally in other mainstream domains (e.g., motor control, action observation, social cognition). In fact, this lack of interest may hinder our understanding of the necessary neurocognitive skills underlying our appetence for transforming our physical environment. Here, we develop the thesis that our technical mind originates in perhaps uniquely human neurocognitive skills, namely, technical-reas…

Single neuron binding properties and the magical number 7

2008

When we observe a scene, we can almost instantly recognize a familiar object or can quickly distinguish among objects differing by apparently minor details. Individual neurons in the medial temporal lobe of humans have been shown to be crucial for the recognition process, and they are selectively activated by different views of known individuals or objects. However, how single neurons could implement such a sparse and explicit code is unknown and almost impossible to investigate experimentally. Hippocampal CA1 pyramidal neurons could be instrumental in this process. Here, in an extensive series of simulations with realistic morphologies and active properties, we demonstrate how n radial (ob…

Spatial-temporal interactions in the human brain

2009

The review summarises current evidence on the cognitive mechanisms for the integration of spatial and temporal representations and of common brain structures to process the where and when of stimuli. Psychophysical experiments document the presence of spatially localised distortions of sub-second time intervals and suggest that visual events are timed by neural mechanisms that are spatially selective. On the other hand, experiments with supra-second intervals suggest that time could be represented on a mental time-line ordered from left-to-right, similar to what is reported for other ordered quantities, such as numbers. Neuroimaging and neuropsychological findings point towards the posterio…

Modulation of excitatory and inhibitory circuits for visual awareness in the human right parietal cortex.

2005

The balance of specific patterns of excitation and inhibition in critical regions of both hemispheres could be relevant in orienting attention over the extrapersonal space. In the present study a group of normal subjects had to detect small rectangular stimuli presented briefly on a computer screen in three different conditions: unilateral presentation either to left or right visual periphery or bilateral simultaneous presentation. Paired transcranial magnetic stimulation (TMS), was applied over the right parietal cortex 150 ms after the presentation of the visual stimuli with different inter-stimulus intervals (ISIs: 1, 3,5 and 10 ms). When paired TMS was applied 150 ms, but not 100 ms, af…

Muslim Atmospheres as Neighbourhoods of Religious Diasporic Microspheres

2016

In many countries around the globe, Muslims not only form a statistical religious minority, but also are mainly regarded as a homogeneous group by the average citizen, the press and politicians. Concepts of Muslim diaspora seem to frequently reinforce this idea, implying that Muslims are building a global community endangering supposedly peaceful cohabitation within nation-states. In contrast, this article, based on a case study in Argentina, shows that diasporic communities can be fruitfully conceptualised as socio-cultural orders with a special ‘atmosphere’, which is formed by the emotional connections between group members and their surroundings, which transcend borders of nation-states.…

Cross-national cultural values and nascent entrepreneurship

2016

This article, differentiating between factual and normative values, investigates the links between national culture and entrepreneurial activity in 24 countries based on 154 observations. We test hypotheses on the relationship between national culture—measured by Global Leadership and Organizational Behavior Effectiveness (GLOBE)—and nascent entrepreneurship as represented by Global Entrepreneurship Monitor (GEM). Both the GEM and the GLOBE databases are robust in terms of forming empirical connections between factual and normative culture and entrepreneurship at the country level. Using these two separate databases to examine our hypotheses enables us to avoid the methodological biases th…

Budd-Chiari Syndrome: Spectrum of Imaging Findings

2007

OBJECTIVE: The objective of our study was to illustrate the imaging findings of Budd-Chiari syndrome, including CT, MRI, sonographic, and angiographic findings. CONCLUSION: The key imaging findings in Budd-Chiari syndrome are occlusion of the hepatic veins, inferior vena cava, or both; caudate lobe enlargement; inhomogeneous liver enhancement; and the presence of intrahepatic collateral vessels and hypervascular nodules. Awareness of these findings is important for early diagnosis and appropriate treatment.

On the tail ofErrivaspisand the condition of the caudal fin in heterostracans

2009

Articulated caudal fins of heterostracans are preserved in very rare cases. Their morphology and internal structure are completely unknown for the majority of species. One of the few preserved caudal fins belongs to the Early Devonian pteraspidid Errivaspis waynensis from the Welsh Borderland, UK. There are two different reconstructions of the tail: (1) strongly asymmetric, with a considerably longer ventral lobe, and a rather concave posterior margin (e.g. White 1935); and (2) almost symmetrical with an only slightly longer ventral lobe and a small notch in the posterior margin (e.g. Blieck 1984). A new reconstruction of the Errivaspis caudal fin, based on a detailed study of White's speci…

Extensive migration of young neurons into the infant human frontal lobe

2016

Building the human brain As the brain develops, neurons migrate from zones of proliferation to their final locations, where they begin to build circuits. Paredes et al. have discovered that shortly after birth, a group of neurons that proliferates near the ventricles migrates in chains alongside circulatory vessels into the frontal lobes (see the Perspective by McKenzie and Fishell). Young neurons that migrate postnatally into the anterior cingulate cortex then develop features of inhibitory interneurons. The number of migratory cells decreases over the first 7 months of life, and by 2 years of age, migratory cells are not evident. Any damage during migration, such as hypoxia, may affect th…