bluuebunny/crossref_metadata_2025 huggingface dataset:
PET may image the gates of awareness, not its center
Authors: Halgren Eric
Published: February 2010

PET detects changes in metabolism between task periods and is thus insensitive to areas that are activated during all or most of cognition. Depth-recorded, evokedpotentials indicate that many multimodal and limbic cortical areas may be activated during most cognitive tasks. Thus, PET may be insensitive to some core processes of awareness that are difficult to eliminate from the control periods.
Neuroimaging studies of language should connect with (psycho)linguistic theories
Authors: Poeppel David , Johnson Susan
Published: February 2010

PET studies in domains like vision and attention have been successful because the experiments are the product of highly articulated theories. In contrast, the results of PET studies investigating language processing are difficult to interpret. We suggest that this difficulty is due to the more tentative connection of these experiments with the insights of psycholinguistics and linguistic theory.
The meaning of baselines
Authors: Robinson David Lee
Published: February 2010

Images of mindsuperbly summarizes work on cognitive neuroscienee using PET scanning. Some of the data emphasized suggests that parietal cortex is involved in the disengagement of attention. We have discovered neurons in awake monkeys which could perform this function. Another point of emphasis is the concept of neutral cues. Although an appealing concept, it is extremely difficult to define what is actually neutral.
Computation, PET images, and attention
Authors: Tsotsos John K.
Published: February 2010

Posner & Raichle (1994) is a nice addition to the Scientific American Library and the average reader will both enjoy the book and learn a great deal. As an activeresearcher, however, I find the book disappointing in many respects. My two major disappointments are in the illusion of computation that is created throughout the volume and in the inadequate perspective of the presentation on visual attention.
Epistemology, two types of functionalism, and first-person authority
Authors: Goldman Alvin I.
Published: February 2010

My target article did not attribute a pervasive ontological significance to phenomenology, so it escapes Bogdan's “epistemological illusion.” Pust correctly pinpoints an ambiguity between contentinclusive and content-exclusive forms of folk functionalism. Contrary to Fodor, however, only the former is plausible, and hence my third argument against functionalism remains a threat. Van Brakel's charity approach to first-person authority cannot deal with authority vis-a-vis sensations, and it has some extremely odd consequences.
Do the calmodulin-stimulated adenylyl cyclases play a role in neuroplasticity?
Authors: Xia Zhengui , Choi Eui-Ju , Storm Daniel R. , Blazynski Christine
Published: February 2010

Evidence from invertebrate systems including Aplysia and Drosophila, as well as studies carried out with mammalian brain, suggests that Ca2+-sensitive adenylyl cyclases may be important for long-term synaptic changes and learning and memory. Furthermore, some forms of long-term potentiation (LTP) in the hippocampus elevate cyclic AMP (cAMP) signals, and activation of adenylyl cyclases and cAMP-dependent protein kinase may be required for late stages of LTP. We propose that long-term changes in neurons and at synapses may require synergism between the cAMP and Ca2+ signal transduction systems which regulates transcription and synthesis of specific proteins required for long-term synaptic changes. During LTP, protein kinase C is activated and intraccllular Ca2+ increases. We hypothesize that the calmodulin (CaM)-regulated adenylyl cyclases may be activated during LTP because of increases in intracellular Ca2+, release of free CaM from neuromodulin, activation by protein kinase C, release of neurotransmitters, or a combination of these events. Synergistic activation of CaM-sensitive adenylyl cyclases may produce a robust or prolonged cAMP signal required for transcriptional control. Furthermore, the coupling of the Ca2+ and cAMP systems may provide positive feedback regulation of Ca2+ channels by cAMP-dependent protein kinase
Correlation of phenotype with genotype in inherited retinal degeneration
Authors: Daiger Stephen P. , Sullivan Lori S. , Rodriguez Joseph A.
Published: February 2010

Diseases causing inherited retinal degeneration in humans, such as retinitis pigmentosa and macular dystrophy, are genetically heterogeneous and clinically diverse. More than 40 genes causing retinal degeneration have been mapped to specific chromosomal sites; of these, at least 10 have been cloned and characterized. Mutations in two proteins, rhodopsin and peripherin/RDS, account for approximately 35% of all cases of autosomal dominant retinitis pigmentosa and a lesser fraction of other retinal conditions. This target article reviews the genes and mutations causing retinal degeneration and proposes mechanisms whereby specific mutations lead to particular clinical consequences, that is, the relationship between genotype and phenotype. Retinitis pigmentosa and macular dystrophy are genetically heterogeneous diseases that cause retinal degeneration in humans and often result in severe visual impairment or blindness. Although many of the genes causing these diseases have not been identified, three photoreceptor-specific proteins have been implicated: rhodopsin, peripherin/RDS, and the P-subunit of rod phosphodiesterase. Mutations in the genes for these three proteins can cause either dominant retinitis pigmentosa, recessive retinitis pigmentosa, dominant congenital stationary night blindness, or dominant macular degeneration. Why this multiplicity of clinical phenotypes? Our target article summarizes the genetic and biochemical background to this question and proposes a number of possible explanations. Discussion focuses mainly on 73 distinct disease-causing mutations of rhodopsin. We feel that rhodopsin and other photoreceptor proteins can serve as model systems for unraveling the connection between genotype and phenotype, not only for inherited retinal diseases but for other degenerative disorders as well.
The structure of rhodopsin and mechanisms of visual adaptation
Authors: Crouch Rosalie K. , Corson D. Wesley
Published: February 2010

Rapidly advancing studies on rhodopsin have focused on new strategies for crystallization of this integral membrane protein for x-ray analysis and on alternative methods for structural determination from nuclear magnetic resonance data. Functional studies of the interactions between the apoprotein and its chromophore have clarified the role of the chromophore in deactivation of opsin and in photoactivation of the pigment.
The key to rhodopsin function lies in the structure of its interface with transducin
Authors: Dratz Edward A.
Published: February 2010

Light activated rhodopsin functions by catalyzing the exchange of GTP for GDP on numerous copies of transducin. Peptide mapping has shown that at least six regions, three on rhodopsin and three on the transducin alpha subunit, are involved in the active interface between the two proteins. The most informative structural studies of rhodopsin should include focus on the transducin interaction.
Does calmodulin play a functional role in phototransduction?
Authors: Gray-Keller Mark P. , Detwiler Peter B.
Published: February 2010

Molday and Hsu review results from invitroexperiments, which indicate that Ca-bound calmodulin reduces the cGMP sensitivity of the cyclic nucleotide-gated channel of photoreceptor cells, and speculate about the role they might play in the recovery of the light response. We discuss results from invivoexperiments that argue against the participation of Ca-calmodulin in photorecovery.
Channel structure and divalent cation regulation of phototransduction
Authors: Hurwitz Richard L. , Srivastava Devesh , Hurwitz Mary Y.
Published: February 2010

The identification of additional subunits of the cGMP-gated cation channel suggests exciting questions about their regulatory roles and about structure/functional relationships. How do the different subunits interact? How is the complex assembled into the plasma membrane? Divalent cations have been implicated in the regulation of adaptation. One often overlooked cation is magnesium. Could this ion play a role in phototransduction?
Linking genotypes with phenotypes in human retinal degenerations: Implications for future research and treatment
Authors: Kaplan Michael W.
Published: February 2010

Although undoubtedly it will be incomplete by the time it is published, the target article by Daiger et al. organizes mutations in genes that produce retinal degenerations in humans into categories of clinically relevant phenotypes. Such classifications should help us understand the link between altered photoreceptor cell proteins and subsequent cell death, and they may yield insight into methods for preventing consequent blindness.
Crucial steps in photoreceptor adaptation: Regulation of phosphodiesterase and guanylate cyclase activities and Ca2+-buffering
Authors: Koch Karl-Wilhelm
Published: February 2010

This commentary discusses the balance of phosphodiesterase and guanylate cyclase activities in vertebrate photoreceptors at moderate light intensities. The rate of cGMP hydrolysis and synthesis seem to equal each other. Ca2+as regulator of both enzyme activities is also effectively buffered in photoreceptor cells by cytoplasmic buffer components.
Gene therapy, regulatory mechanisms, and protein function in vision
Authors: McGinnis James F.
Published: February 2010

Hereditary retinal degeneration due to mutations in visual genes may be amenable to therapeutic interventions that modulate, either positively or negatively, the amount of protein product. Some of the proteins involved in phototransduction are rapidly moved by a lightdependent mechanism between the inner segment and the outer segment in rod photoreceptor cells, and this phenomenon is important in phototransduction.
Modulation of the cGMP-gated channel by calcium
Authors: Sagoo Mandeep S. , Lagnado Leon
Published: February 2010

Calcium acting through calmodulin has been shown to regulate the affinity of cyclic nucleotide-gated channels expressed in cell lines. But is calmodulin the Ca-sensor that normally regulates these channels?
A novel protein family of neuronal modulators
Authors: Takamatsu Ken
Published: February 2010

A number of proteins homologous to recoverin have been identified in the brains of the several vertebrate species. The brainderived members originally contain four EF-hand domains, but NH2-terminal domain is aberrant. Many of these proteins inhibited light-induced rhodopsin phosphorylation at high [Ca2+], suggesting that the brain-derived members may act as a Ca2+-sensitive modulator of receptor phosphorylation, as recoverin does.
Cyclic nucleotides as regulators of light-adaptation in photoreceptors
Authors: Willardson Barry M. , Yoshida Tatsuro , Bitensky Mark W.
Published: February 2010

Cyclic nucleotides can regulate the sensitivity of retinal rods to light through phosducin. The phosphorylation state of phosducin determines the amount of G available for activation by Rho*. Phosducin phosphorylation is regulated by cyclic nucleotides through their activation of cAMP-dependent protein kinase. The regulation of phosphodiesterase activity by the noncatalytic cGMP binding sites as well as Ca2+/calmodulin dependent regulation of cGMP binding to the cation channel are also discussed.
Future directions for rhodopsin structure and function studies
Authors: Hargrave Paul A.
Published: February 2010

NMR (nuclear magnetic resonance) may be useful for determining the structure of retinal and its environment in rhodopsin, but not for determining the complete protein structure. Aggregation and low yield of fragments of rhodopsin may make them difficult to study by NMR. A long-term multidisciplinary attack on rhodopsin structure is required.
Genetic and functional complexity of inherited retinal degeneration
Authors: Daiger Stephen P. , Sullivan Lori S. , Rodriguez Joseph A.
Published: February 2010

Recent findings emphasize the complexity, both genetic and functional, of the manifold genes and mutations causing inherited retinal degeneration in humans. Knowledge of the genetic bases of these diseases can contribute to design of rational therapy, as well as elucidating the function of each gene product in normal visual processes.
Sociopathy, evolution, and the brain
Authors: Barratt Ernest S. , Gardner Russell
Published: February 2010

We propose that Mealey's model is limited in its description of sociopathy because it does not provide an adequate role for the main organ mediating genes and behavior, namely, the brain. Further, on the basis of our research, we question the view of sociopaths as a homogeneous group.
Secondary sociopathy and opportunistic reproductive strategy
Authors: Belsky Jay
Published: February 2010

Mealey's analysis of secondary sociopathy has much in common with Belsky, Steinberg, and Draper's (1991) evolutionary theory of socialization. Both draw attention to the potential influence of early rearing in the promotion of a cold, detached, manipulative, and opportunistic style of relating to others and, in so doing, raise the question of whether secondary sociopathy represents a facultative reproductive strategy.
Putting cognition into sociopathy
Authors: Blair R. J. R. , Morton John
Published: February 2010

We make three suggestions with regard to Mealey's work. First, her lack of a cognitive analysis of the sociopath results in underspecified mappings between sociobiology and behavior. Second, the developmental literature indicates that Mealey's implicit assumption, that moral socialisation is achieved through punishment, is invalid. Third, we advance the use of causal modelling to map the developmental relationships between biology, cognition, and behaviour.
Sociopathy or hyper-masculinity?
Authors: Campbell Anne
Published: February 2010

Definitional slippage threatens to equate secondary sociopathy with mere criminality and leaves the status of noncriminal sociopaths ambiguous. Primary sociopathy appears to show more environmental contingency than would be implied by a strong genetic trait approach. A reinterpretation in terms of hypermasculinity and hypofemininity is compatible with the data.
Prisoner's Dilemma, Chicken, and mixedstrategy evolutionary equilibria
Authors: Colman Andrew M.
Published: February 2010

Mealey's interesting interpretation of sociopathy is based on an inappropriate two-person game model. A multiperson, compound game version of Chicken would be more suitable, because a population engaging in random pairwise interactions with that structure would evolve to an equilibrium in which a fixed proportion of strategic choices was exploitative, antisocial, and risky, as required by Mealey's interpretation.
Sociopathy and sociobiology: Biological units and behavioral units
Authors: Erickson Carl J.
Published: February 2010

Behavioral biologists have long sought to link behavioral units (e.g., aggression, depression, sociopathy) with biological units (e.g., genes, neurotransmitters, hormones, neuroanatomical loci). These units, originally contrived for descriptive purposes, often lead to misunderstandings when they are reified for purposes of causal analysis. This genetic and biochemical explanation for sociopathy reflects such problems.
The primary/secondary distinction of psychopathy: A clinical perspective
Authors: Gudjonsson Gisli H.
Published: February 2010

In this brief commentary the author concentrates on the treatment perspectives of Mealey's model. The main weakness of the model is that it does not provide a satisfactory theoretical connection between treatment and different types of target behavior. Even within the primary-secondary distinction, there are large individual differences that should not be overlooked in the planning of treatment.
Genes, hormones, and gender in sociopathy
Authors: Hoyenga Katharine
Published: February 2010

Although serotonin, testosterone, and genes contribute to sociopathy, the relationships are probably indirect and subject to modifiers (e.g., present only under certain conditions of rearing and temperament). Age at menarche may be a marker variable as well as a causal factor. Since the genders differ in all four areas, sex differences in sociopathy represent a very complex interaction of these factors.
An evaluation of Mealey's hypotheses based on psychopathy checklist: Identified groups
Authors: Kosson David S. , Newman Joseph P.
Published: February 2010

Although Mealey's account provides several interesting hypotheses, her integration across disparate samples renders the value of her explanation for psychopathy ambiguous. Recent evidence on Psychopathy Checklist-identified samples (Hare, 1991) suggests primary emotional and cognitive deficits inconsistent with her model. Whereas high-anxious psychopaths display interpersonal deficits consistent with Mealey's hypotheses, low-anxious psychopaths' deficits appear more sensitive to situational parameters than predicted.
Genetic issues in “the sociobiology of sociopathy”
Authors: Maxson Stephen C.
Published: February 2010

A consideration of the genetics of sociopathy suggests the following. The author's Evolutionary Stable Strategy (ESS) types 2 to 4 are more likely than types 1 and 5 in crimes of violence, and there may not be an ESS for crimes of property or for sociopathy. Correlations between sociopathy and crimes of property are also more likely due to environmental than to genetic variants, and correlations between sociopathy and crimes of property are due more to environmental than genetic variants.
Pathways to sociopathy: Twin analyses offer direction
Authors: Segal Nancy L.
Published: February 2010

Understanding the bases of complex behavioral phenotypes, such as sociopathy, is assisted by an evolutionary approach, in addition to other theoretical perspectives. Unraveling genetic and environmental factors underlying variant forms of sociopathy remains a key challenge for behavioral science investigators. Twin research methods (e.g., longitudinal analyses; twins reared apart) offer informative means of assessing novel hypotheses relevant to sociopathic behaviors.
Is sociopathy a type or not? Will the “real” sociopathy please stand up?
Authors: Snyder James
Published: February 2010

The validity of the classification of “primary sociopaths” as a qualitatively distinct group in the general population is questioned. Cenetic variation in the experience and expression of emotions may play a role in the development of antisocial behavior. However, research clearly documents that socialization environments powerfully modify the expression of genetic biases in a manner that increases or decreases the risk for “sociopathy.”
The role of attachment in the development and prevention of sociopathy
Authors: Van IJzendoorn Marinus H.
Published: February 2010

Mealey's sociobiological model of sociopathy could profit from attachment theory, in particular, the theory and research on the basis of the Adult Attachment Interview (Main & Goldwyn 1985–1993). Findings of an adult attachment study in a forensic psychiatric setting are summarized. Three attachment-oriented strategies for families, schools, and forensic settings are proposed to help reduce or prevent secondary sociopathy and criminal recidivism.
Sociopathy within and between small groups
Authors: Wilson David Sloan
Published: February 2010

If sociopathy is a biological adaptation, it probably evolved in small social groups in which individuals lacked the social mobility required for a con-man strategy to work. On the other hand, conflicts between groups may have provided a large niche for sociopathy throughout human history.
Moral judgments by alleged sociopaths as a means for coping with problems of definition and identification in Mealey's model
Authors: Wolf Yuval
Published: February 2010

Problems of definition and identification in the integrated evolutionary model of sociopathy are suggested by Schoenfeld's (1974) criticism of the field of race differences in intelligence. Moral judgments by those labeled primary and secondary sociopaths may offer a way to validate the assumptions of the model.
Weight and mass as psychophysical attributes
Authors: Ross Helen E.
Published: February 2010

In terms of physics, mass is the fixed attribute of an object while weight varies with the accelerative force. Neither weight nor mass are simple sensory stimuli as both involve the integration of sensory and motor information with higher cognitive processes. Studies of apparent heaviness yield only vague information about sensorimotor mechanisms.
The Hebbian paradigm reintegrated: Local reverberations as internal representations
Authors: Amit Daniel J.
Published: February 2010

The neurophysiological evidence from the Miyashita group's experiments on monkeys as well as cognitive experience common to us all suggests that local neuronal spike rate distributions might persist in the absence of their eliciting stimulus. In Hebb's cell-assembly theory, learning dynamics stabilize such self-maintaining reverberations. Quasi-quantitive modeling of the experimental data on internal representations in association-cortex modules identifies the reverberations (delay spike activity) as the internal code (representation). This leads to cognitive and neurophysiological predictions, many following directly from the language used to describe the activity in the experimental delay period, others from the details of how the model captures the properties of the internal representations.
The Hebbian paradigm reintegrated: Local reverberations as internal representations
Authors: Freeman Walter J.
Published: February 2010

Recurrent excitation is experimentally well documented in cortical populations. It provides for intracortical excitatory biases that linearize negative feedback interactions and induce macroscopic state transitions during perception. The concept of the local neighborhood should be expanded to spatial patterns as the basis for perception, in which large areas of cortex are bound into cooperative behavior with near-silent columns as important as active columns revealed by unit recording.
Additional tests of Amit's attractor neural networks
Authors: Hoffman Ralph E.
Published: February 2010

Further tests of Amit's model are indicated. One strategy is to use the apparent coding sparseness of the model to make predictions about coding sparseness in Miyashita's network. A second approach is to use memory overload to induce false positive responses in modules and biological systems. In closing, the importance of temporal coding and timing requirements in developing biologically plausible attractor networks is mentioned.
Another ANN model for the Miyashita experiments
Authors: Morita Masahiko
Published: February 2010

The Miyashita experiments are very interesting and the results should be examined from a viewpoint of attractor dynamics. Amit's target article shows a path toward realistic modeling by artificial neural networks (ANN), but it is not necessarily the only one. I introduce another model that can explain a substantial part of the empirical observations and makes an interesting prediction. This model consists of such units that have nonmonotonic input-output characteristics with local inhibition neurons.
Local or transcortical assemblies? Some evidence from cognitive neuroscience
Authors: Pulvermüller Friedemann , Preissl Hubert
Published: February 2010

Amit defines cell assemblies aslocal cortical neuron populationswith strong internal connections. However, Hebb himself proposed that cell assemblies are distributed over different cortical areas (nonlocal ortranscortical assemblies). We review evidence from cognitive neuroscience and neuropsychology supporting the assumption that cell assemblies are transcortical.
How to decide whether a neural representation is a cognitive concept?
Authors: Raijmakers Maartje E. J. , Molenaar Peter C. M.
Published: February 2010

A distinction should be made between the formation of stimulus-driven associations and cognitive concepts. To test the learning mode of a neural network, we propose a simple and classic input-output test: the discrimination shift task. Feed-forward PDP models appear to form stimulus-driven associations. A Hopfield network should be extended to apply the test.
Reverberations of Hebbian thinking
Authors: Rauschecker Josef P.
Published: February 2010

Cortical reverberations may induce synaptic changes that underlie developmental plasticity as well as long-term memory. They may be especially important for the consolidation of synaptic changes. Reverberations in cortical networks should have particular significance during development, when large numbers of new representations are formed. This includes the formation of representations across different sensory modalities.
Association and computation with cell assemblies
Authors: der van Velde Frank
Published: February 2010

The cell assembly is an important concept for cognitive psychology. Cognitive processing will to a large extent depend on the relations that can exist between different assemblies. A potential relation between assemblies can already be seen in the occurrence of (classical) conditioning. However, the resulting associations between assemblies only produce behavioristic processing or so-called regular computation. Higher-level cognitive abilities most likely result from nonregular computation. I discuss the possibility of this form of computation in terms of cell assemblies.
Empirical and theoretical active memory: The proper context
Authors: Amit Daniel J.
Published: February 2010

The context of the target article is delimited again, underlining the intended locationof the argument in the bottomup hierarchy of brain study. The central message is that collective delay activity distributions (reverberations) in cortical modules extend the role of a spike (a potentialinformation carrier across long distances) to an active memory of structured, learned information that can be carried across long time intervals. Moreover, the population code of the reverberations makes them readable down the cortical processing stream. Most of the critical comments are then interpreted and addressed in relation to misreading of the proper context. The price for the limitation of the context (in cognitive, behavioral, and computational terms) is compared with the advantages of a clear, direct contact with experiment on the one hand and with a well controlled body of modeling and analysis on the other.
Consciousness, memory, and the hippocampal system: What kind of connections can we make?
Authors: Eichenbaum Howard , Cohen Neal J.
Published: February 2010

Gray's account is remarkable in its depth and scope but too little attention is paid to poor correspondences with the literature on hippocampal/subicular damage, the theta rhythm, and novelty detection. An alternative account, focusing on hippocampal involvement in organizing memories in a way that makes them accessible to conscious recollection but not in access to consciousness per se, avoids each of these limitations.
Context and consciousness
Authors: Ellard Colin G.
Published: February 2010

The commentary argues (1) that we cannot be sure that human consciousness has survival value and (2) that in order to understand the origins and, perhaps, the function of consciousness, we should examine the behavioural and neural precursors to consciousness in nonhumans. An example is given of research on the role of context in decisions regarding fleeing from probable predators in the Mongolian gerbil.
Consciousness is for other people
Authors: Frith Chris
Published: February 2010

Gray has expanded his account of schizophrenia to explain consciousness as well. His theory explains neither phenomenon adequately because he treats individual minds (and brains) in isolation. The primary function of consciousness is to permit high level interactions with other conscious beings. The key symptoms of schizophrenia reflect a failure of this mechanism.
Correlating mind and body
Authors: Lioyd-Jones T. J. , Donnelly N. , Weekes B.
Published: February 2010

Gray's integration of the different levels of description and explanation in his theory is problematic: (1) The introduction of consciousness into his theorising consists of the mind-brain identity assumption, which tells us nothing new. (2) There need not be correlations between levels of description. (3) Gray's account does not extend beyond “brute” correlation. Integration must be achieved in a principled, mutually constraining way.
Reticular-thalamic activation of the cortex generates conscious contents
Authors: Newman James
Published: February 2010

Gray hypothesizes that the contents of consciousness correspond to the outputs of a subicular (hippocampal/temporal lobe) comparator that compares the current state of the organism's perceptual world with a predicted state. I argue that Gray has identified a key contributing system to conscious awareness, but that his model is inadequate for explaining how conscious contents are generated in the brain. An alternative model is offered.
Communication and consciousness: A neural network conjecture
Authors: Schmajuk N. A. , Axelrad E.
Published: February 2010

The communicative aspects of the contents of consciousness are analyzed in the framework of a neural network model of animal communication. We discuss some issues raised by Gray, such as the control of the contents of consciousness, the adaptive value of consciousness, conscious and unconscious behaviors, and the nature of a model's consciousness.
Consciousness beyond the comparator
Authors: Shames Victor A. , Hubbard Timothy L.
Published: February 2010

Gray's comparator model fails to provide an adequate explanation of consciousness for two reasons. First, it is based on a narrow definition of consciousness that excludes basic phenomenology and active functions of consciousness. Second, match/mismatch decisions can be made without producing an experience of consciousness. The model thus violates the sufficiency criterion.
Consciousness does not seem to be linked to a single neural mechanism
Authors: Umiltà Carlo , Zorzi Marco
Published: February 2010

On the basis of neuropsychological evidence, it is clear that attention should be given a role in any model (or conjecture) of consciousness. What is known about the many instances of dissociation between explicit and implicit knowledge after brain damage suggests that conscious experience might not be linked to a restricted area of the brain. Even if it were true that there is a single brain area devoted to consciousness, the subicular area would seem to be an unlikely possibility.
Consciousness and its (dis)contents
Authors: Gray Jeffrey A.
Published: February 2010

The first claim in the target article was that there is as yet no transparent, causal account of the relations between consciousness and brain-and-behaviour. That claim remains firm. The second claim was that the contents of consciousness consist, psychologically, of the outputs of a comparator system; the third consisted of a description of the brain mechanisms proposed to instantiate the comparator. In order to defend these claims against criticism, it has been necessary to clarify the distinction between consciousness-as-such and the contents of consciousness, to widen the description of the neural machinery instantiating the comparator system, and to clarify the relationship between the contents of consciousness in the here-and-now and episodic memory.
The lambda model is only one piece in the motor control puzzle
Authors: Dean Jeffrey
Published: February 2010

The lambda model provides a physiologically grounded terminology for describing muscle function and emphasizes the important influence of environmental and reflex-mediated effects on final states. However, lambda itself is only a convenient point on the length-tension curve; its importance should not be overemphasized. Ascribing movement to changes in a lambda-based frame of reference is generally valid, but it leaves unanswered a number of questions concerning mechanisms.
Natural unconstrained movements obey rules different from constrained elementary movements
Authors: Desmurget Michel , Rossetti Yves , Prablanc Claude
Published: February 2010

The concept of a conservative control strategy minimizing the number of degrees of freedom used is criticised with reference to 3-D simple reaching and grasping experiments. The vector error in a redundant system would not be the prime controlled variable, but rather the posture for reaching, as exemplified by nearly straight displacements in joint space as opposed to curved ones in task space.
The lambda model and a hemispheric motor model of intentional hand movements
Authors: Fidelman Uri
Published: February 2010

The lambda model of Feldman & Levin for intentional hand movement is compared with a hemispheric motor model (IIMM). Both models imply similar conclusions independently. This increases the validity of both models.
Is λ an appropriate control variable for locomotion?
Authors: Hamm Thomas M. , Han Zong-Sheng
Published: February 2010

The lambda model predicts that the command received by each motor nucleus during locomotion is specific for the joint at which its muscle acts and is independent of external conditions. However, investigation of the commands received by motor nuclei during fictive locomotion and of the sensitivity of these commands to feedback from the limb during locomotion indicates that neither condition is satisfied.
The unobservability of central commands: Why testing hypotheses is so difficult
Authors: Hodgson Antony
Published: February 2010

The experiments Feldman and Levin suggest do not definitively test their proposed solution to the problem of selecting muscle activations. Their test of the movement directions that elicit EMG activity can be interpreted without regard to the form of the central commands, and their fast elbow flexion test is based on a forward computation that obscures the insensitivity of the predicted trajectory to the details of the putative commands.
Can the λ model benefit from understanding human adaptation in weightlessness(and vice versa)?
Authors: McDonald P. Vernon
Published: February 2010

Parameters of the lambda model seem tightly linked to certain characteristics of human performance influenced by weightlessness. This commentary suggests that there is a valuable opportunity to probe the lambda model using the changed environment experienced during space flight. The likely benefits are a better model and a better understanding ofthe consequences of weightlessness for human performance.
Let us accept a “controlled trade-off” model of motor control
Authors: Partridge Lloyd D.
Published: February 2010

The trade-off between force and length of muscle as adjusted by neural signals is a critical fact in the dynamics of motor control. Whether we call it “length-tension effect,” “feedback-like,” “invariant condition,” or “spring-like” is unimportant. We must not let semantics or details of representation obscure the basic physics of effects introduced by this trade-off in muscle.
Position is everything?
Authors: Pribram Karl H.
Published: February 2010

Neurophysiological evidence consonant with F&L's lambda model is reviewed and results of additional experiments are presented. The evidence shows that there are neurons in the motor cortex that respond to selective band widths of passive sinusoidal movements; the additional data show how, with movement, directionally sensitive population vectors can be shown to emerge from the data.
Can the λ model be used to interpret the activity of single neurons?
Authors: Scott Stephen H.
Published: February 2010

Whereas the λ model provides a useful technique to describe complex movements, the focus on control variables in this model limits its potential for interpreting the activity and function of many cells in motor areas of the CNS.
Levers to generate movement
Authors: Windhorst U.
Published: February 2010

The following questions are discussed: (1) Who determines the nature of “control variables”? (2) Is the “positional monopoly” healthy? (3) Does a descending command alter reflex threshold alone without eoncomitantly altering stiffness? (4) How does the CNS deal with history-dependent effects? (5) Should we abandon the idea that the CNS controls classical Newtonian variables such as muscle length?
How far should we extend the equilibrium point (lambda) hypothesis?
Authors: Winters Jack M.
Published: February 2010

A key feature of the lambda model is the hypothesis of a local spring-like muscle-reflex system defined by a central control variable that has units of position. This is intriguing, especially for a study of postural stability in large-scale systems, but it has limited direct application to skilled everyday movements. If movement is considered as a goal-directed, neuro-optimization problem, however, theavailabilityof lambda-like peripheral models (vs. conventional musculoskeletal models) deserves exploration.
The λ model for motor control: More than meets the eye
Authors: Levin Mindy F. , Feldman Anatol G.
Published: February 2010

Understanding of the λ model has greatly increased in recent years as evidenced by most of the commentaries. Some commentators underscored the potential of the model to integrate aspects of different sensorimotor systems in the production of movement. Other commentators focused on not-yet-fully-developed parts of the model. A few persisted in misunderstanding some of its basic concepts, and on these grounds they reject it. In responding to commentaries we continue to elaborate on some fundamental points of the model, especially control variables, the idea of movement production by shifting the positional frame of reference and the hypothesis of biomechanical correspondence in motor control. We also continue to develop our ideas on the intrinsic generation of the frame of reference associated with external space and utilized for the control of arm movement and locomotion. The dynamic principles underlying the model are discussed in light of the dynamical systems approach.
Consciousness and timing
Authors: Salter David
Published: February 2010

This commentary addresses three distinctions: the relationship of conscious to unconscious processes, whether these processes are single or multiple, and the distinction between vehicle and content. Also considered are questions of the relationship between multiple drafts to consciousness, the oneness of phenomenal perception as an illusion, the role of consciousness in the redrafting process, and finally the update frequency for attentional revision.
Cognitive algebra versus representativeness heuristic
Authors: Anderson Norman H.
Published: February 2010

Cognitive algebra strongly disproved the representativeness heuristic almost before it was published; and therewith it also disproved the base rate fallacy. Cognitive algebra provides a theoretical foundation for judgment-decision theory through its joint solution to the two fundamental problems – true measurement of subjective values, and cognitive rules for integration of multiple determinants.
The purpose of experiments: Ecological validity versus comparing hypotheses
Authors: Dawes Robyn M.
Published: February 2010

As illustrated by research Koehler himself cites (Dawes et al. 1993), the purpose of experiments is to choose between contrasting explanations of past observations – rather than to seek statistical generalizations about the prevalence of effects. True external validity results not from sampling various problems that are representative of “real world” decision making, but from reproducing an effect in the laboratory with minimal contamination (including from real world factors).
Base rates, experience, and the big picture
Authors: Edgell Stephen E. , Roe Robert M. , Dodd Clayton H.
Published: February 2010

The important question is how people process probabilistic information, not whether they process it in accordance with a normative model that we never should have expected them to be capable of following. Experience is not the cure, as widely thought, to problems with utilizing base rate information.
Base rates, stereotypes, and judgmental accuracy
Authors: Funder David C.
Published: February 2010

The base rate literature has an opposite twin in the social psychological literature on stereotypes, which concludes that people use their preexisting beliefs about probabilistic category attributes too much, rather than not enough. This ironic discrepancy arises because beliefs about category attributes enhance accuracy when the beliefs are accurate and diminish accuracy when they are not. To determine the accuracy of base rate/stereotype beliefs requires research that addresses specific content.
Why do frequency formats improve Bayesian reasoning? Cognitive algorithms work on information, which needs representation
Authors: Gigerenzer Gerd
Published: February 2010

In contrast to traditional research on base-rate neglect, an ecologically-oriented research program would analyze the correspondence between cognitive algorithms and the nature of information in the environment. Bayesian computations turn out to be simpler when information is represented in frequency formats as opposed to the probability formats used in previous research. Frequency formats often enable even uninstructed subjects to perform Bayesian reasoning.
The base rate controversy: Is the glass half-full or half-empty?
Authors: Keren Gideon , Thijs Lambert J.
Published: February 2010

Setting the two hypotheses of complete neglect and full use of base rates against each other is inappropriate. The proper question concerns the degree to which base rates are used (or neglected), and under what conditions. We outline alternative approaches and recommend regression analysis. Koehler's conclusion that we have been oversold on the base rate fallacy seems to be premature.
First things first: What is a base rate?
Authors: McCauley Clark
Published: February 2010

The fallacy beneath the base rate fallacy is that we know what a base rate is. We talk as if base rates and individuating information were two different kinds of information. From a Bayesian perspective, however, the only difference between base rate and individuating information is – which comes first.
The implicit use of base rates in experiential and ecologically valid tasks
Authors: Spellman Barbara A.
Published: February 2010

When base rates are learned and used in an experiential manner subjects show better base rate use, perhaps because the implicit learning system is engaged. A causal framework in which base rates are relevant might also be necessary. Humans might thus perform better on more ecologically valid tasks, which are likely to contain those three components.
“Normal” is not the issue: It is “effective” goal attainment that counts
Authors: Carr J. H. , Shepherd R. B.
Published: February 2010

Adaptive motor patterns that emerge after a neuromusculoskeletal lesion reflect not only the primary lesion, but also the dynamic characteristics of the musculoskeletal linkage and environment in which the action is performed. Although these patterns may be optimal, they may also be ineffective as goal-directed actions; effectiveness may only be regained if training addresses primary deficits and ensures practice without gross biomechanical adaptations.
Anticipatory postural mechanisms: Some evidence and methodological implications
Authors: Kasai Tatsuya
Published: February 2010

To understand the basic priorities of the central nervous system in human motor control, neurophysiological parameters are important. Certain H-reflex methods related to anticipatory postural control are particularly useful and may have therapeutic implications.
What are “normal movements” inanypopulation?
Authors: Masters R. S. W. , Polman R. C. J.
Published: February 2010

It is the contention of Latash & Anson (L&A) that in atypical populations, such as those with cognitive, central neurological, or peripheral disorders, the central nervous system (CNS) is capable of producing more effective, though often less “normal,” movement patterns ifleft to its own devices. It is the aim of this commentary to extend their argument to other populations by pointing out the many parallels with development of movement patterns in sport.
How functional are atypical motor patterns?
Authors: Scholz John P.
Published: February 2010

Latash & Anson are commended for pointing out that investigators of atypical motor performance have too often failed to recognize the adaptive nature of many atypical movement characteristics. However, the authors' assumption that atypical motor patterns can be considered “normal” and, by implication, that it is futile to attempt to teach different patterns to patients that may be more functional, is criticized.
Generic mechanisms of coordination in special populations
Authors: Treffner Paul J. , Kelso J. A. Scott
Published: February 2010

We show that left-handers can be considered as a “special” population. We indicate that the asymmetries in performance exhibited by left-handers are due to a basic asymmetry in the underlying coordination dynamics that constrains bimanual coordination. In contrast to the claims of Latash & Anson, we argue that considerable knowledge has been gained regarding the essential equations of motion that govern biological coordination.
Language and its role in understanding intentional relations: Research tool or mechanism of development?
Authors: Budwig Nancy , Bamberg Michael
Published: February 2010

In our commentary we elaborate on Barresi & Moore's use of language as a tool. In particular, we highlight the importance of cognitive linguistic research with its emphasis on the relation between morpnosyntax and intentional schemes. We also speculate about how language itself might play a role in children's integration of first and third person knowledge.
An ambiguity
Authors: Church Jennifer
Published: February 2010

The difference between first and third person information may be thought of as a difference in either informationalcontentor informationalmodality. Each option faces some problems. I try to sort out some of these issues and raise a question about the explanatory force of the notion of a schema.
Rhesus monkeys are radical behaviorists
Authors: Gallup Gordon G.
Published: February 2010

The data reviewed in Barresi & Moore's treatment of social understanding is recast in terms of a model of social intelligence that was advanced some time ago (Gallup 1982). When it comes to their analysis of the behavior of other individuals, most primates (and humans younger than 18 months of age) appear to function as radical behaviorists, whereas chimpanzees and older infants show evidence of becoming primitive cognitive psychologists.
First person representations need a methodology based on simulation or theory
Authors: Gordon Robert M.
Published: February 2010

Although their thesis is generally sound, Barresi & Moore give insufficient attention to the need for a methodology, whether simulation based or theory-based, for choosing among alternative possible matches of first person and third person information. This choice must be sensitive to contextual information, including past behavior. Moreover, apart from simulation or theory, first person information would not help predict future behavior.
Understanding that looking causes knowing
Authors: Olson David R. , Homer Bruce
Published: February 2010

Barresi & Moore provide an impressive account of how the coordination of first and third person information about the self and other could produce an account of intentional relations. They are less explicit as to how the child comes to understand the basic epistemic relation between experience and knowledge, that is, how informational access causes belief. We suggest one route.
Social relations and understanding the intentional self
Authors: Oosterwegel Annerieke
Published: February 2010

Although Barresi & Moore could have grounded their framework more explicitly in existing models, they offer a provocative testbed for the assumptions of symbolic interactionism and further thinking about self-regulation, especially in autistics.