CiteULike: butterchicken's library [8 articles]

Latency of locating lights and sounds

WE Simpson — 2008-05-05T02:36:37-00:00

Journal of Experimental Psychology, Vol. 93, No. 1. (April 1972), pp. 169-175.

Tested the hypothesis that auditory localization processes are more complex than visual localization processes in 3 experiments with 58 undergraduates. Stimulus azimuth and auditory intensity were varied as was response mode key pressing or verbalization ("right," "left"). RT for localization was compared against simple RT control data. Analyses of mean RT and variability of RT support the hypothesis. Giving S foreknowledge of the modality of a stimulus affected simple and localization RTs equally, indicating that stimulus uncertainty did not affect localization per se. (PsycINFO Database Record (c) 2006 APA, all rights reserved)

Cognitive load selectively interferes with utilitarian moral judgment

Joshua Greene — 2008-05-05T02:35:19-00:00

Cognition, Vol. 107, No. 3. (June 2008), pp. 1144-1154.

Traditional theories of moral development emphasize the role of controlled cognition in mature moral judgment, while a more recent trend emphasizes intuitive and emotional processes. Here we test a dual-process theory synthesizing these perspectives. More specifically, our theory associates utilitarian moral judgment (approving of harmful actions that maximize good consequences) with controlled cognitive processes and associates non-utilitarian moral judgment with automatic emotional responses. Consistent with this theory, we find that a cognitive load manipulation selectively interferes with utilitarian judgment. This interference effect provides direct evidence for the influence of controlled cognitive processes in moral judgment, and utilitarian moral judgment more specifically.

Discontinuity in the enumeration of sequentially presented auditory and visual stimuli.

Valérie Camos — 2007-12-13T13:46:02-00:00

Cognition (7 December 2007)

The seeking of discontinuity in enumeration was recently renewed because Cowan [Cowan, N. (2001). The magical number 4 in short-term memory: A reconsideration of mental storage capacity. Behavioral and Brain Sciences, 24, 87-185; Cowan, N. (2005). Working memory capacity. Hove: Psychology Press] suggested that it allows evaluating the limit of the focus of attention, currently estimated at four items. A strong argument in favour of a general constraint of the cognitive system is that similar discontinuities should be observed in modalities different from the classic simultaneous presentation of visual objects. Recently, data were provided on tactile stimuli, but the authors diverged in their conclusion about the existence of such discontinuity [Gallace, A., Tan, H. Z., & Spence, C. (2006). Numerosity judgments for tactile stimuli distributed over the body surface. Perception, 35(2), 247-266; Riggs, K. J., Ferrand, L., Lancelin, D., Fryziel, L., Dumur, G., & Simpson, A. (2006). Subitizing in tactile perception. Psychological Science, 17(4), 271-272]. Following a similar rationale, our study aimed at evaluating discontinuity in the enumeration of auditory and visual stimuli presented sequentially. The clear and similar discontinuity observed in error rates, response times and given responses for both modalities favours the general capacity limit view, but also questions the size of this capacity, because the discontinuity occurred here at size 2. However, the masking of stimuli in sensory memory could not be entirely discarded.

Implementation of a galvanically isolated low-noise power supply board for multi-channel headstage preamplifiers

Attila Tóth — 2008-05-05T02:33:46-00:00

Journal of Neuroscience Methods, Vol. 171, No. 1. (15 June 2008), pp. 13-18.

Custom made multi-channel headstage preamplifiers are traditionally powered by battery. By the use of an isolated unregulated DC/DC converter integrated circuit (DCP010512B from Texas Instruments Inc., TX, USA), here we describe the implementation of a galvanically isolated low-noise power supply board for multi-channel headstage preamplifiers. The implemented galvanically isolated power supply board provides the same quality noise free recording as the battery power supply. The non-isolated part of the power supply board is powered by standard 230 V AC/6 V DC wall mount adapter or USB cable. The described galvanically isolated power supply board can replace the batteries in preamplifier power supplies without any deterioration of the quality of recordings.

Artificial dural sealant that allows multiple penetrations of implantable brain probes

Nathan Jackson — 2008-05-02T09:35:28-00:00

Journal of Neuroscience Methods, Vol. 171, No. 1. (15 June 2008), pp. 147-152.

This study reports extensive characterization of the silicone gel (3-4680, Dow Corning, Midland, MI), for potential use as an artificial dural sealant in long-term electrophysiological experiments in neurophysiology. Dural sealants are important to preserve the integrity of the intracranial space after a craniotomy and in prolonging the lifetime and functionality of implanted brain probes. In this study, we report results of our tests on a commercially available silicone gel with unique properties that make it an ideal dural substitute. The substitute is transparent, elastic, easy to apply, and has re-sealing capabilities, which makes it desirable for applications where multiple penetrations by the brain probe is desirable over an extended period of time. Cytotoxicity tests (for up to 10 days) with fibroblasts and in vivo tests (for 12 weeks) show that the gel is non-toxic and does not produce any significant neuronal degeneration when applied to the rodent cortex even after 12 weeks. In vivo humidity testing showed no sign of CSF leakage for up to 6 weeks. The gel also allows silicon microprobes to penetrate with forces less than 0.5 mN, and a 200-[mu]m diameter stainless steel microprobe with a blunt tip to penetrate with a force less than 2.5 mN. The force dependency on the velocity of penetration and thickness of the gel was also quantified and empirically modeled. The above results demonstrate that the silicone gel (3-4680) can be a viable dural substitute in long-term electrophysiology of the brain.

Does the chimpanzee have a theory of mind? 30 years later

Josep Call — 2008-05-03T20:33:29-00:00

Trends in Cognitive Sciences, Vol. 12, No. 5. (May 2008), pp. 187-192.

On the 30th anniversary of Premack and Woodruff's seminal paper asking whether chimpanzees have a theory of mind, we review recent evidence that suggests in many respects they do, whereas in other respects they might not. Specifically, there is solid evidence from several different experimental paradigms that chimpanzees understand the goals and intentions of others, as well as the perception and knowledge of others. Nevertheless, despite several seemingly valid attempts, there is currently no evidence that chimpanzees understand false beliefs. Our conclusion for the moment is, thus, that chimpanzees understand others in terms of a perception-goal psychology, as opposed to a full-fledged, human-like belief-desire psychology.

Neuron -- Schoppik et al.

2008-05-05T00:53:34-00:00

Cognitive control, hierarchy, and the rostro-caudal organization of the frontal lobes

David Badre — 2008-05-05T00:52:17-00:00

Trends in Cognitive Sciences, Vol. 12, No. 5. (May 2008), pp. 193-200.

Cognitive control supports flexible behavior by selecting actions that are consistent with our goals and appropriate for our environment. The prefrontal cortex (PFC) has an established role in cognitive control, and research on the functional organization of PFC promises to contribute to our understanding of the architecture of control. A recently popular hypothesis is that the rostro-caudal axis of PFC supports a control hierarchy whereby posterior-to-anterior PFC mediates progressively abstract, higher-order control. This review discusses evidence for a rostro-caudal gradient of function in PFC and the theories proposed to account for these results, including domain generality in working memory, relational complexity, the temporal organization of behavior and abstract representational hierarchy. Distinctions among these frameworks are considered as a basis for future research.