To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Corporate accountability actions brought under the Alien Tort Statute (ATS) tend to be grounded more in hope than in expectation. While an effective publicity tool for highlighting allegations of corporate irresponsibility and a successful approach for gaining favorable settlements in a few high-profile cases, U.S. courts have generally been reluctant to use the ATS to hold global corporations accountable for their actions outside the United States.
I had a role in making it possible to visualize the working of the human brain while it is engaged in thought. The development of neuroimaging has made it possible to connect the abstract mental operations or computations studied by cognitive psychology with the brain areas studied by neuroscience and helped to establish cognitive neuroscience as a field within psychology. Here, I tell the history of how my role in visualizing the human brain came about.
Vernon Mountcastle was one of the pioneers of modern brain research. His work with animals showed that the basic functional unit of the brain was the cortical column. In 1978, I read a paper of his describing attention cells in the posterior part of the parietal cortex of alert monkeys. He suggested that these attention cells might be critically involved in orienting attention toward visual events. A Tuesday night meeting of our research group was assigned to read these papers. Our group had shown that reaction time to respond to a target was enhanced when a cue directed attention to the target location. We interpreted this to mean that attention had been oriented covertly to the location of the target, without any overt change in eye position or behavior. I asked the students whether the reaction time improvements were the results of the attention cells observed by Mountcastle. I thought that if the covert shifts of attention in humans could be connected with the monkey work, it might contribute to linking cognitive psychology to brain mechanisms. I don't think there was much enthusiasm for this idea at the time. After all, the slogan in cognitive psychology was that it was about software, and what did that have to do with the parts of the brain in which cells were found in the monkey?
In 1979, I met Oscar Marin, an outstanding behavioral neurologist, at a meeting in New York City. He was about to move to Portland, Oregon, to set up a clinical and research effort at Good Samaritan Hospital, and he invited me to set up a neuropsychology laboratory in conjunction with the hospital.
A novel deposition process has been developed for manufacturing of high quality rare-earth doped glass films with complex composition. This process, Laser Reactive Deposition (LRDTM), comprises photothermal laser pyrolysis using an aerosol feedstock coupled with deposition of the resulting nanoparticle product onto Si substrates with our without an underlying glass film. This paper describes this novel process as well as the structure, properties and performance of the Erdoped, multicomponent silicate glass films produced to date with this process.
Nanoscale apertures that provide a fluidic path between two reservoirs can be used for numerous applications. These applications include patch-clamp type measurements, Coulter counting and molecular studies. For Coulter counting of nanometer-sized analytes, we have developed a process capable of reproducibly fabricating cylindrical apertures in a silicon-on-insulator substrate with diameters less than 30 nm. The fabrication process utilizes electron beam lithography for the lithographic definition of the apertures enabling accurate control of final device dimensions. Measurements of the conductance of the pores as a function of KCl concentration reveal the presence of a surface conduction mechanism that dominates the conductance of the nanopore and leads to a deviation of the concentration dependence of the conductance from the case of bulk solution. From current traces recorded, the passage of individual particles through the pore can be concluded.
The term plasticity is often confined to changes due to learning. We believe, however, that the rapid lability of human behavior as different mental contents receive attention represents an important form of plasticity. Recent research in temperament and cognitive neuroscience provides an account of the development of a specific neural system involved in attentional self-regulation. In this paper, we concentrate on a network involved in orienting. We describe what is currently known about this network and its development during the first years of life. This network interacts with other attentional networks that come to control orienting to remembered events as well as those currently present. Orienting reflects processes that are both deeply biological and also open to cultural influences through learning. Attention is influenced by the current emotional state and is also important in achieving control over the emotional state. We present evidence on how learning influences eye position between 4 and 18 months of life and indicate influences of orienting on important aspects of infant behavior. Like any biological system, problems can arise in these mechanisms. We speculate on how individual differences in distress proneness and orienting may relate to the development of psychopathology.
Two significant scientific contributions, brain images and gene sequences, are helping scientists and educators to understand individual differences in the acquisition of cognitive and emotional skills. Research on brain mechanisms of attention in children and adults shows three independent neuronal networks for alerting, orienting, and executive control in conflict resolution. The authors' attention network test evaluates the efficiency of each of these three systems and reveals clear individual differences, which relate to evaluations of children's ability to regulate their own behavior. Among factors affecting this capacity for regulation are two genes related to the neurotransmitter dopamine, which relate to both performance and activation of a node of the attention network in the anterior cingulate. From early childhood, effortful control of attention plays a role not only in learning but also in socialization and empathy. Understanding attention regulation and its relation to learning will clearly be informative to teachers and parents.
Two major developments have greatly altered the prospects for making a connection between common networks of the human brain and theories of how people differ. First, with the development of neuroimaging, we could glimpse inside the human brain as people think (Posner & Raichle, 1994). When combined with electrical or magnetic recording from outside the skull, it was possible to see in real time the circuits involved in computing aspects of a task.
The three chapters that follow this introduction all deal with aspects of visual perception related to the processing of scenes and the recognition of objects. There was a time when it was clear that higher order visual perception meant processing that took place in brain areas beyond the primary visual cortex. The primary visual cortex was thought to perform simple computations, each covering a small separate part of the visual world (receptive field) and hard wired in the sense that little could be done by learning or attention to modify them. This view stressed hierarchical processing among visual areas, particularly those from primary visual cortex V1 to the anterior temporal areas. Evidence for the hierarchical view is thoroughly summarized in the chapter by Kastner, De Weerd, and Ungerleider. However, all the three chapters deal in rather different ways with qualification to the hierarchical view of visual areas driven passively from the bottom up, based upon the influence of context, attention, and task demands.
In his chapter, Charles Gilbert describes the research work of his group, which has changed the view of how the primary visual cortex works. The older view gave rise to the hope that studies of primary visual cortex might provide the basic immutable building blocks from which it might be possible to launch an analysis of the remaining functions grouped under the title of higher perception.
Michael I. Posner, Professor Emeritus Psychology Department University of Oregon Eugene, Oregon 97403-1227,
Jin Fan, Department of Psychiatry Icahn Medical Institute 1425 Madison Avenue, Room 20-82 Mount Sinai School of Medicine One Gustave L. Levy Place, Box 1228 New York, NY 10029
Attention is relatively easy to define subjectively as in the classical definition of William James (1890) who said: “Everyone knows what attention is. It is the taking possession of the mind in clear and vivid form of one out of what seem several simultaneous objects or trains of thought.”
However, this subjective definition does not provide hints that might lead to an understanding of attentional development or pathologies. The theme of our chapter is that it is now possible to view attention much more concretely as an organ system. We follow the Webster dictionary definition of an organ system: “An organ system may be defined as differentiated structures in animals and plants made up of various cell and tissues and adapted for the performance of some specific function and grouped with other structures into a system.”
We believe that viewing attention as an organ system aids in answering many perplexing issues raised in cognitive psychology, psychiatry, and neurology. Neuroimaging studies have systemically shown that a wide variety of cognitive tasks can be seen as activating a distributed set of neural areas, each of which can be identified with specific mental operations (Posner & Raichle, 1994, 1998). Perhaps the areas of activation have been more consistent for the study of attention than for any other cognitive system. We can view attention as involving specialized networks to carry out functions such as achieving and maintaining the alert state, orienting to sensory events, and controlling thoughts and feelings.
We examined the influence of a common allelic variation in the dopamine receptor D4 (DRD4) gene and caregiver quality on temperament in early childhood. Children 18–21 months of age were genotyped for the DRD4 48 base pair tandem repeat polymorphism, which has been implicated in the development of attention, sensation seeking, and attention-deficit/hyperactivity disorder. The children also interacted with their caregiver for 10 min in a laboratory setting, and these videotaped interactions were coded for parenting quality using an observational rating procedure. The presence of the DRD4 7-repeat allele was associated with differences in the influence of parenting on a measure of temperamental sensation seeking constructed from caregiver reports on children's activity level, impulsivity, and high-intensity pleasure. Children with the 7-repeat allele were influenced by parenting quality, with lower quality parenting associated with higher levels of sensation seeking; children without the 7-repeat allele were uninfluenced by parenting quality. Differences between alleles were not related to the child's self-regulation as assessed by the effortful control measure. Previous studies have indicated that the 7-repeat allele is under positive selective pressure, and our results are consistent with the hypothesis that the DRD4 7-repeat allele increased children's sensitivity to environmental factors such as parenting. This study shows that genes influence the relation between parenting and temperament in ways that are important to normal development and psychopathology.