ECVP2010 pictures

http://ecvp2010.epfl.ch/index.php?page=pics

De-motivator of the day:

Eight year olds get published:

 

http://gawker.com/5715860/eight+year+olds-publish-study-in-respected-science-journal

Infants and toddlers show enlarged visual sensitivity to nonaccidental compa...

 

 

Sent to you by Frouke via Google Reader:

 

 

Infants and toddlers show enlarged visual sensitivity to nonaccidental compared with metric shape changes. Greet Kayaert , Johan Wagemans

via i-Perception by Pion on 12/20/10

Some shape changes are more important for object perception than others. We used a habituation paradigm to measure visual sensitivity to a nonaccidental shape change—that is, the transformation of a trapezium into a triangle and vice versa—and a metric shape change—that is, changing the aspect ratio of the shapes. Our data show that an enhanced perceptual sensitivity to the nonaccidental change is already present in infancy and remains stable into toddlerhood. We have thus established an example of how early visual perception deviates from the null hypothesis of representing similarity as a function of physical overlap between shapes, and does so in agreement with more cognitive, categorical demands.

 

 

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The shading cue in context. Johan Wagemans, Andrea J van Doorn, Jan J Koende...

 

 

Sent to you by Frouke via Google Reader:

 

 

The shading cue in context. Johan Wagemans, Andrea J van Doorn, Jan J Koenderink

via i-Perception by Pion on 12/21/10

The shading cue is supposed to be a major factor in monocular stereopsis. However, the hypothesis is hardly corroborated by available data. For instance, the conventional stimulus used in perception research, which involves a circular disk with monotonic luminance gradient on a uniform surround, is theoretically 'explained' by any quadric surface, including spherical caps or cups (the conventional response categories), cylindrical ruts or ridges, and saddle surfaces. Whereas cylindrical ruts or ridges are reported when the outline is changed from circular to square, saddle surfaces are never reported. We introduce a method that allows us to differentiate between such possible responses. We report observations on a number of variations of the conventional stimulus, including variations of shape and quality of the boundary, and contexts that allow the observer to infer illumination direction. We find strong and expected influences of outline shape, but, perhaps surprisingly, we fail to find any influence of context, and only partial influence of outline quality. Moreover, we report appreciable differences within the generic population. We trace some of the idiosyncrasies (as compared to shape from shading algorithms) of the human observer to generic properties of the environment, in particular the fact that many objects are limited in size and elliptically convex over most of their boundaries.

 

 

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http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WBY-51JTYBV-1&_user=1394575&_coverDate=11%2F26%2F2010&_rdoc=13&_fmt=high&_orig=browse&_origin=browse&_zone=rslt_list_item&_srch=doc-info%28%23toc%236723%239999%23999999999%2399999%23FLA%23display%23Articles%29&_cdi=6723&_sort=d&_docanchor=&_ct=17&_acct=C000047079&_version=1&_urlVersion=0&_userid=1394575&md5=b75e7b854c3a1dff98adc629d19ee1e6&searchtype=a

ERP evidence of visualization at early stages of visual processing

Jonathan W. Pagea, Corresponding Author Contact Information, E-mail The
Corresponding Author, Paul Duhamelb and Michael A. Crognalec

a Department of Psychology, Minnesota State University, Mankato, MN, USA

b Department of Human Kinetics, Laurentian University, Sudbury, Ontario,
Canada

c Department of Psychology, University of Nevada, Reno, NV, USA
Accepted 1 November 2010.
Available online 26 November 2010.

Abstract

Recent neuroimaging research suggests that early visual processing
circuits are activated similarly during visualization and perception but
have not demonstrated that the cortical activity is similar in character.
We found functional equivalency in cortical activity by recording evoked
potentials while color and luminance patterns were viewed and while they
were visualized with the eyes closed. Cortical responses were found to be
different when imagining a color pattern vs. imagining a checkerboard
luminance pattern, but the same when imagining a color pattern (or
checkerboard pattern) vs. seeing the same pattern. This suggests that
early visual processing stages may play a dynamic role in internal image
generation, and further implies that visual imagery may modulate
perception.

--
Suggested reading by Ervin

http://app.psychonomic-journals.org/content/72/6/1510.abstract

Voluntary attention increases perceived spatial frequency

1. Jared Abrams,
2. Antoine Barbot and
3. Marisa Carrasco

New York University, New York, New York

Abstract

Voluntary covert attention selects relevant sensory information for
prioritized processing. The behavioral and neural consequences of such
selection have been extensively documented, but its phenomenology has
received little empirical investigation. Involuntary attention increases
perceived spatial frequency (Gobell & Carrasco, 2005), but involuntary
attention can differ from voluntary attention in its effects on
performance in tasks mediated by spatial resolution (Yeshurun, Montagna, &
Carrasco, 2008). Therefore, we ask whether voluntary attention affects the
subjective appearance of spatial frequency—a fundamental dimension of
visual perception underlying spatial resolution. We used a demanding rapid
serial visual presentation task to direct voluntary attention and measured
perceived spatial frequency at the attended and unattended locations.
Attention increased the perceived spatial frequency of suprathreshold
stimuli and also improved performance on a concurrent orientation
discrimination task. In the control experiment, we ruled out response bias
as an alternative account by using a lengthened interstimulus interval,
which allows observers to disengage attention from the cued location. In
contrast to the main experiment, the observers showed neither increased
perceived spatial frequency nor improved orientation discrimination at the
attended location. Thus, this study establishes that voluntary attention
increases perceived spatial frequency. This phenomenological consequence
links behavioral and neurophysiological studies on the effects of
attention.

--
Suggested reading by Ervin

http://www.journalofvision.org/content/10/12/27.abstract

What are the units of storage in visual working memory?

1. Daryl Fougnie
2. Christopher L. Asplund
3. René Marois

Abstract

An influential theory suggests that integrated objects, rather than
individual features, are the fundamental units that limit our capacity to
temporarily store visual information (S. J. Luck & E. K. Vogel, 1997).
Using a paradigm that independently estimates the number and precision of
items stored in working memory (W. Zhang & S. J. Luck, 2008), here we show
that the storage of features is not cost-free. The precision and number of
objects held in working memory was estimated when observers had to
remember either the color, the orientation, or both the color and
orientation of simple objects. We found that while the quantity of stored
objects was largely unaffected by increasing the number of features, the
precision of these representations dramatically decreased. Moreover, this
selective deterioration in object precision depended on the multiple
features being contained within the same objects. Such fidelity costs were
even observed with change detection paradigms when those paradigms placed
demands on the precision of the stored visual representations. Taken
together, these findings not only demonstrate that the maintenance of
integrated features is costly; they also suggest that objects and features
affect visual working memory capacity differently.

--
Suggested reading by Ervin

Identification of everyday objects on the basis of Gaborized outline version...

 

 

Sent to you by Frouke via Google Reader:

 

 

Identification of everyday objects on the basis of Gaborized outline versions. Michaël Sassi, Kathleen Vancleef, Bart Machilsen, Sven Panis, Johan Wagemans

via i-Perception by Pion on 12/2/10

Using outlines derived from a widely used set of line drawings, we created stimuli geared towards the investigation of contour integration and texture segmentation using shapes of everyday objects. Each stimulus consisted of Gabor elements positioned and oriented curvilinearly along the outline of an object, embedded within a larger Gabor array of homogeneous density. We created six versions of the resulting Gaborized outline stimuli by varying the orientations of elements inside and outside the outline. Data from two experiments, in which participants attempted to identify the objects in the stimuli, provide norms for identifiability and name agreement, and show differences in identifiability between stimulus versions. While there was substantial variability between the individual objects in our stimulus set, further analyses suggest a number of stimulus properties which are generally predictive of identification performance. The stimuli and the accompanying normative data, both available on our website (http://www.gestaltrevision.be/sources/gaboroutlines), provide a useful tool to further investigate contour integration and texture segmentation in both normal and clinical populations, especially when top-down influences on these processes, such as the role of prior knowledge of familiar objects, are of main interest.

 

 

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ERP evidence of visualization at early stages of visual processing

Feed: ScienceDirect Publication: Brain and Cognition
Posted on: dinsdag 30 november 2010 7:13
Author: ScienceDirect Publication: Brain and Cognition
Subject: ERP evidence of visualization at early stages of visual processing

 

Publication year: 2010 Source: Brain and Cognition, In Press, Corrected Proof, Available online 26 November 2010 Jonathan W., Page , Paul, Duhamel , Michael A., Crognale Recent neuroimaging research suggests that early visual processing circuits are activated similarly during visualization and perception but have not demonstrated that the cortical activity is similar in character. We found functional equivalency in cortical activity by recording evoked potentials while color and luminance patterns were viewed and while they were visualized with the eyes closed. Cortical responses were found to be different when imagining a color pattern vs. imagining a checkerboard luminance pattern, but the same when imagining a color pattern (or checkerboard pattern) vs. seeing the same pattern. This suggests that early visual processing stages may play a dynamic...

View article...

Suggested by Maarten

Integration of contour and surface information in shape detection

Sure everyone knows this work...

 

 

Sent to you by Frouke via Google Reader:

 

 

Integration of contour and surface information in shape detection

via ScienceDirect Publication: Vision Research on 11/17/10

Publication year: 2010
Source: Vision Research, In Press, Accepted Manuscript, Available online 17 November 2010
Bart, Machilsen , Johan, Wagemans
In studies of shape perception, the detection of contours and the segregation of regions enclosed by these contours have mostly been treated in isolation. However, contours and surfaces somehow need to be combined to create a stable perception of shape. In this study, we used a 2AFC task with arrays of oriented Gabor elements to determine whether and to what extent human observers integrate information from the contour and from the interior surface of a shape embedded in this array. The saliency of the shapes depended on the alignment of Gabors along the shape outline and on the isolinearity of...

 

 

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Some classics

Can be found at this website:

http://psychclassics.yorku.ca/topic.htm#gestalt

----
Krista Overvliet, PhD.
 
Laboratory of  Experimental Psychology
University of Leuven
Tiensestraat 102, bus 3711
Room 04.03
3000 Leuven
Belgium
 
phone: +3216326146
skype: kristaovervliet
krista.overvliet@gmail.com
krista.overvliet@psy.kuleuven.be
http://web.me.com/krista.overvliet

FW: Perceptual Organization Without Perception: The Subliminal Learning of Global Contour

 

 

Feed: Psychological Science RSS feed -- Preview Articles
Posted on: 23 November 2010 21:08
Author: Rosenthal, O., Humphreys, G. W.
Subject: Perceptual Organization Without Perception: The Subliminal Learning of Global Contour

 

A critical step in visual perceptual processing is integrating local visual elements into contours so that shapes can be derived from them. It is often assumed that contour integration may reflect hardwired coding of low-level visual features. In this study, we present novel evidence indicating that integration of local elements into contours can be learned subliminally, despite being irrelevant to the training task and despite the local properties of the display varying randomly during training. Learning occurred only when contours were consistently paired with task-relevant targets—echoing the findings of previous studies on subliminal learning of low-level features. Our data indicate that task-irrelevant, exposure-based learning extends beyond local low-level visual features and may play a critical role at multiple levels of visual perceptual organization.

View article...

"Rond tien uur doken we met een lawaaierige bende acht- tot dertienjarigen een aula van de Oude Valk in, benieuwd naar wat professor in de experimentele psychologie Johan Waegemans ons daar een uur lang zou vertellen over "kijken met je hersenen". Lang geleden dat wij een aula nog zo tot de nok vol hadden gezien. Lang geleden dat wij zoveel vlijt en ongeremdheid bijeen zagen..." http://www.veto.be/veto/veto3706/KIND.html

MEG Responses to the Perception of Global Structure within Glass Patterns

 

 

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MEG Responses to the Perception of Global Structure within Glass Patterns

via PLoS ONE Alerts: Neuroscience door Jennifer B. Swettenham et al. op 5-11-10

Background

The perception of global form requires integration of local visual cues across space and is the foundation for object recognition. Here we used magnetoencephalography (MEG) to study the location and time course of neuronal activity associated with the perception of global structure from local image features. To minimize neuronal activity to low-level stimulus properties, such as luminance and contrast, the local image features were held constant during all phases of the MEG recording. This allowed us to assess the relative importance of striate (V1) versus extrastriate cortex in global form perception.

Methodology/Principal Findings

Stimuli were horizontal, rotational and radial Glass patterns. Glass patterns without coherent structure were viewed during the baseline period to ensure neuronal responses reflected perception of structure and not changes in local image features. The spatial distribution of task-related changes in source power was mapped using Synthetic Aperture Magnetometry (SAM), and the time course of activity within areas of maximal power change was determined by calculating time-frequency plots using a Hilbert transform. For six out of eight observers, passive viewing of global structure was associated with a reduction in 10–20 Hz cortical oscillatory power within extrastriate occipital cortex. The location of greatest power change was the same for each pattern type, being close to or within visual area V3a. No peaks of activity were observed in area V1. Time-frequency analyses indicated that neural activity was least for horizontal patterns.

Conclusions

We conclude: (i) visual area V3a is involved in the analysis of global form; (ii) the neural signature for perception of structure, as assessed using MEG, is a reduction in 10–20 Hz oscillatory power; (iii) different neural processes may underlie the perception of horizontal as opposed to radial or rotational structure; and (iv) area V1 is not strongly activated by global form in Glass patterns.

 

 

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Neuroscience meets magic

Neuroscience TV

 

 

Sent to you by Frouke via Google Reader:

 

 

Neuroscience meets magic

via Scientific American on 10/28/10

Brain scientists Stephen Macknik and Susana Martinez-Conde explain the science behind the mental manipulations of gentleman thief Apollo Robbins.

 

 

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• Subscribe to Scientific American using Google Reader
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Perceptual Learning in Vision Research

Review on perceptual learning

 

 

Feed: ScienceDirect Publication: Vision Research
Posted on: dinsdag 26 oktober 2010 6:07
Author: ScienceDirect Publication: Vision Research
Subject: Perceptual Learning in Vision Research

 

Publication year: 2010 Source: Vision Research, In Press, Accepted Manuscript, Available online 23 October 2010 Dov, Sagi Reports published in Vision Research during the late years of the 20th century described surprising effects of long-term sensitivity improvement with some basic visual tasks as a result of training. These improvements, found in adult human observers, were highly specific to simple visual features, such as location in the visual field, spatial-frequency, local and global orientation, and in some cases even the eye of origin. The results were interpreted as arising from the plasticity of sensory brain regions that display those features of specificity within their constituting neuronal subpopulations. A new view of the visual cortex has emerged, according to...

View article...

Suggested by Maarten

fhermens@yahoo.com has sent you a New Scientist story.

Your friend thought you should see this article on newscientist.com today.

Moving illusions: Now you see it, now you don't
http://www.newscientist.com/article/dn19611

Some articles may require a login, available free to all subscribers to New Scientist magazine.

You can subscribe at http://www.newscientist.com/subscribe.

Their message:
The fading seems to work too with moving random dots. Is the conclusion that these dots are grouped?

NewScientist.com is the world's leading online science and technology news service, with a global network of award-winning journalists. Visit www.newscientist.com now for constantly updated and authoritative reporting that's both fast and fascinating.

Detection of Convexity and Concavity in Context

Feed: ScienceDirect Publication: Journal of Experimental Psychology: Human Perception and Performance
Posted on: zaterdag 23 oktober 2010 7:23
Author: ScienceDirect Publication: Journal of Experimental Psychology: Human Perception and Performance
Subject: Detection of Convexity and Concavity in Context

 

Publication year: 2008 Source: Journal of Experimental Psychology: Human Perception and Performance, Volume 34, Issue 4, August 2008, Pages 775-789 Marco, Bertamini Sensitivity to shape changes was measured, in particular detection of convexity and concavity changes. The available data are contradictory. The author used a change detection task and simple polygons to systematically manipulate convexity/concavity. Performance was high for detecting a change of sign (a new concave vertex along a convex contour or a new convex vertex along a concave contour). Other things being equal, there was no evidence of an advantage for detecting a new concavity compared with a new convexity, for detecting a change of angle to a concave vertex compared with a convex vertex, for detecting a change within...

View article...

Suggested by Maarten

50 ideas to change science: Neuroscience

 

 

Sent to you by Frouke via Google Reader:

 

 

50 ideas to change science: Neuroscience

via New Scientist - Online News on 10/14/10

Thanks to better brain imaging and biological insights, we're closing in on the neurons of consciousness and the subtleties of our mental machinery

 

 

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Reversed Tilt Effect for Dichoptic Stimulation in Vertical Meridian

 

 

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Reversed Tilt Effect for Dichoptic Stimulation in Vertical Meridian

via ScienceDirect Publication: Vision Research op 11-10-10

Publication year: 2010
Source: Vision Research, In Press, Accepted Manuscript, Available online 10 October 2010
Gerald, Westheimer
The orientation of a test line appears shifted away from that of contextual contours. This repulsion in the orientation domain manifests itself in, for example, the tilt aftereffect, the simultaneous orientation contrast, and the Zöllner illusion. Attractive rather than repulsive interaction has been reported for collinear inducing configurations at small inducing angles. Here it is shown that the tilt induced in a monocular vertical foveal test line by a single centered inducing line is repulsive when both are in the same eye, but becomes attractive for dichoptic stimulation. This occurs for only a narrow range of test-line/inducing-line separations and varies...

 

 

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The exploitation of Gestalt principles by magicians

http://www.perceptionweb.com/abstract.cgi?id=p6766

I have the PDF on my computer, so just send me an email if you're interested.

----
Krista Overvliet, PhD.
 
Laboratory of  Experimental Psychology
University of Leuven
Tiensestraat 102, bus 3711
Room 04.03
3000 Leuven
Belgium
 
phone: +3216326146
skype: kristaovervliet
krista.overvliet@gmail.com
krista.overvliet@psy.kuleuven.be
http://web.me.com/krista.overvliet

Retina is structured to process an excess of darkness in natural scenes

Feed: Proceedings of the National Academy of Sciences current issue
Posted on: dinsdag 5 oktober 2010 18:48
Author: Ratliff, C. P., Borghuis, B. G., Kao, Y.-H., Sterling, P., Balasubramanian, V.
Subject: Retina is structured to process an excess of darkness in natural scenes [Neuroscience]

 

Retinal ganglion cells that respond selectively to a dark spot on a brighter background (OFF cells) have smaller dendritic fields than their ON counterparts and are more numerous. OFF cells also branch more densely, and thus collect more synapses per visual angle. That the retina devotes more resources to processing dark contrasts predicts that natural images contain more dark information. We confirm this across a range of spatial scales and trace the origin of this phenomenon to the statistical structure of natural scenes. We show that the optimal mosaics for encoding natural images are also asymmetric, with OFF elements smaller and more numerous, matching retinal structure. Finally, the concentration of synapses within a dendritic field matches the information content, suggesting a simple principle to connect a concrete fact of neuroanatomy with the abstract concept of information: equal synapses for equal bits.

View article...

Suggested by Maarten

Orientation selectivity of motion-boundary responses in human visual cortex.

http://www.ncbi.nlm.nih.gov/pubmed/20861432?dopt=Abstract

-----------------------------------------------------------------------
Naoki Kogo, PhD
Laboratory of Experimental Psychology
Department of Psychology, University of Leuven, Belgium
-----------------------------------------------------------------------

Intrinsic biophysical diversity decorrelates neuronal firing while increasing information content

http://www.nature.com/neuro/journal/v13/n10/full/nn.2630.html
http://www.nature.com/neuro/journal/v13/n10/full/nn1010-1158.html#/ref5

-----------------------------------------------------------------------
Naoki Kogo, PhD
Laboratory of Experimental Psychology
Department of Psychology, University of Leuven, Belgium
-----------------------------------------------------------------------

FW: Contributions of Ideal Observer Theory to Vision Research

 

 

Feed: ScienceDirect Publication: Vision Research
Posted on: 04 October 2010 06:31
Author: ScienceDirect Publication: Vision Research
Subject: Contributions of Ideal Observer Theory to Vision Research

 

Publication year: 2010 Source: Vision Research, In Press, Accepted Manuscript, Available online 2 October 2010 Wilson S., Geisler An ideal observer is a hypothetical device that performs optimally in a perceptual task given the available information. The theory of ideal observers has proven to be a powerful and useful tool in vision research, which has been applied to a wide range of problems. Here I first summarize the basic concepts and logic of ideal observer analysis and then briefly describe applications in a number of different areas, including pattern detection, discrimination and estimation, perceptual grouping, shape, depth and motion perception and visual attention, with an emphasis on recent applications. Given recent advances in mathematical statistics, in computational power,...

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Attentional facilitation throughout human visual cortex lingers in retinotopic coordinates after eye movements.

http://www.ncbi.nlm.nih.gov/pubmed/20685992

-----------------------------------------------------------------------
Naoki Kogo, PhD
Laboratory of Experimental Psychology
Department of Psychology, University of Leuven, Belgium
-----------------------------------------------------------------------

The role of top-down task context in learning to perceive objects.

http://www.ncbi.nlm.nih.gov/pubmed/20660269

-----------------------------------------------------------------------
Naoki Kogo, PhD
Laboratory of Experimental Psychology
Department of Psychology, University of Leuven, Belgium
-----------------------------------------------------------------------

The prefrontal cortex modulates category selectivity in human extrastriate cortex.

http://www.ncbi.nlm.nih.gov/pubmed/20586702

-----------------------------------------------------------------------
Naoki Kogo, PhD
Laboratory of Experimental Psychology
Department of Psychology, University of Leuven, Belgium
-----------------------------------------------------------------------

Prefrontal Cortex Tunes Category Selectivity in Visual Association Cortex.

http://www.ncbi.nlm.nih.gov/pubmed/20681751

-----------------------------------------------------------------------
Naoki Kogo, PhD
Laboratory of Experimental Psychology
Department of Psychology, University of Leuven, Belgium
-----------------------------------------------------------------------

Neural tuning for face wholes and parts in human fusiform gyrus revealed by FMRI adaptation.

http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&TermToSearch=20505126

-----------------------------------------------------------------------
Naoki Kogo, PhD
Laboratory of Experimental Psychology
Department of Psychology, University of Leuven, Belgium
-----------------------------------------------------------------------

Relationships between the threshold and slope of psychometric and neurometric functions during perceptual learning: implications for neuronal pooling.

http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&TermToSearch=19864439

-----------------------------------------------------------------------
Naoki Kogo, PhD
Laboratory of Experimental Psychology
Department of Psychology, University of Leuven, Belgium
-----------------------------------------------------------------------

Mechanisms of pattern decorrelation by recurrent neuronal circuits.

http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&TermToSearch=20581841
population code, decorrelation

-----------------------------------------------------------------------
Naoki Kogo, PhD
Laboratory of Experimental Psychology
Department of Psychology, University of Leuven, Belgium
-----------------------------------------------------------------------

How reliable is the pattern adaptation technique? A modeling study.

http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&TermToSearch=19553490
frequency adaptation

-----------------------------------------------------------------------
Naoki Kogo, PhD
Laboratory of Experimental Psychology
Department of Psychology, University of Leuven, Belgium
-----------------------------------------------------------------------

FW: Decoupling object detection and categorization.

 

 

Feed: Journal of Experimental Psychology: Human Perception and Performance - Vol 36, Iss 5
Posted on: 23 August 2010 02:00
Author: Mack, Michael L.; Palmeri, Thomas J.
Subject: Decoupling object detection and categorization.

 

We investigated whether there exists a behavioral dependency between object detection and categorization. Previous work (Grill-Spector & Kanwisher, 2005) suggests that object detection and basic-level categorization may be the very same perceptual mechanism: As objects are parsed from the background they are categorized at the basic level. In the current study, we decouple object detection from categorization by manipulating the between-category contrast of the categorization decision. With a superordinate-level contrast with people as one of the target categories (e.g., cars vs. people), which replicates Grill-Spector and Kanwisher, we found that success at object detection depended on success at basic-level categorization and vice versa. But with a basic-level contrast (e.g., cars vs. boats) or superordinate-level contrast without people as a target category (e.g., dog vs. boat), success at object detection did not depend on success at basic-level categorization. Successful object detection could occur without successful basic-level categorization. Object detection and basic-level categorization do not seem to occur within the same early stage of visual processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)

View article...

[MATLAB] My first use of sendmail

The official Matlab blog featured a short article recently on a function that could be of use to some people: ‘sendmail’. If you set it up correctly, Matlab can send out e-mails to keep you updated on its progress while you’re away from your work computer, or automatically e-mail you the data as soon as a subject finishes an experiment.

 

http://blogs.mathworks.com/loren/2010/09/16/my-first-use-of-sendmail/?s_cid=fb_wall_loren_sendmail

 

 

For instance, to send from your kuleuven e-mail, you could use something like this.

 

address = 'yourname@gmail.com';                         % The e-mail address to which to send

subject = 'Matlab progress report';                     % The e-mail subject

message = 'Matlab finished creating your stimuli';      % The body of the message

attachname = 'stimuli.mat';                             % An attachment

mail = 'yourname@psy.kuleuven.be';                      % The e-mail address from which to send

username = 'u0000000';                                  % Your u-number

password = 'mypassword';                                % Your password

 

% Settings for kuleuven e-mail sending

setpref('Internet','E_mail',mail);

setpref('Internet','SMTP_Server','smtps.kuleuven.be');

setpref('Internet','SMTP_Username',username);

setpref('Internet','SMTP_Password',password);

 

props = java.lang.System.getProperties;

props.setProperty('mail.smtp.auth','true');

props.setProperty('mail.smtp.socketFactory.class', 'javax.net.ssl.SSLSocketFactory');

props.setProperty('mail.smtp.socketFactory.port','443');

 

% Sendmail example without attachment

sendmail(address,subject,message)

 

% Sendmail example with attachment

sendmail(address,subject,message,'stimuli.mat')

 

 

Beware though, having your KUL password saved in a plain text m-file can be a security risk. You could try to use a less sensitive e-mail account if this bothers you, or be more inventive in how you enter the password into the program (e.g., load it from a .mat file, make up or download a simple encryption routine,…).

 

Greetings,

Maarten

Fwd: Signal detection theory, uncertainty, and Poisson-like population codes

------- Forwarded message -------
From: "ScienceDirect Publication: Vision Research" <>
To:
Cc:
Subject: Signal detection theory, uncertainty, and Poisson-like population codes
Date: Wed, 08 Sep 2010 06:23:41 +0200

Publication year: 2010
Source: Vision Research, In Press, Accepted Manuscript, Available online 7 September 2010

Wei Ji, Ma

The juxtaposition of established signal detection theory models of perception and more recent claims about the encoding of uncertainty in perception is a rich source of confusion. Are the latter simply a rehash of the former? Here, we make an attempt to distinguish precisely between optimal and probabilistic computation. In optimal computation, the observer minimizes the expected cost under a posterior probability distribution. In probabilistic computation, the observer uses higher moments of the likelihood function of the stimulus on a trial-by-trial basis. Computation can be optimal without being probabilistic, and vice versa. Most signal detection theory models describe optimal computation....

---

Article:

• http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=IRSSCONTENT&_method=citationSearch&_piikey=S004269891000430X&_version=1&md5=ab8f30671b3d09ce997d455f3c117f3c

--

Suggested reading by Kathleen

Neural bases of the non-conscious perception of emotional signals

Could be relevant for those interested in the influence of emotion on visual perception processes.

 

 

Feed: Nature Reviews Neuroscience - Issue - nature.com science feeds
Posted on: donderdag 2 september 2010 2:00
Author: Marco Tamietto
Subject: Neural bases of the non-conscious perception of emotional signals

 

Neural bases of the non-conscious perception of emotional signals Nature Reviews Neuroscience 11, 697 (2010). doi:10.1038/nrn2889 Authors: Marco Tamietto & Beatrice de Gelder Many emotional stimuli are processed without being consciously perceived. Recent evidence indicates that subcortical structures have a substantial role in this processing. These structures are part of a phylogenetically ancient pathway that has specific functional properties and that interacts with cortical processes. There is now

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Suggested by Maarten

Situating visual search

A review/opinion on visual search tasks and the organization of the visual brain

 

 

Feed: ScienceDirect Publication: Vision Research
Posted on: vrijdag 17 september 2010 6:31
Author: ScienceDirect Publication: Vision Research
Subject: Situating visual search

 

Publication year: 2010 Source: Vision Research, In Press, Accepted Manuscript, Available online 15 September 2010 Ken, Nakayama , Paolo, Martini Visual search attracted great interest because its ease under certain circumstances seemed to provide a way to understand how properties of early visual cortical areas could explain complex perception without resorting to higher order psychological or neurophysiological mechanisms. Furthermore, there was the hope that properties of visual search itself might even reveal new cortical features or dimensions. The shortcomings of this perspective suggest that we abandon fixed canonical elementary particles of vision as well as a corresponding simple-to-complex cognitive architecture for vision. Instead recent research has suggested a different organization of the visual brain with putative high level processing occurring...

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Suggested by Maarten

Nieuwe verkeersremmer: 3D-illusie van spelend meisje

 

 

http://www.standaard.be/artikel/detail.aspx?artikelid=DMF20100909_032

Research on horribly cute kittens is kind of horrible looking

A history lesson, probably not suitable for cat lovers...

 

 

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Research on horribly cute kittens is kind of horrible looking

via Boing Boing door Maggie Koerth-Baker op 3-9-10

"In order to study the way that experience can influence the brain, there has been a great deal of research done on the visual cortex of the kitten."

Oh, this is going to end badly, isn't it?

This short documentary from the 1970s explains, in depth, some research that I mentioned earlier this year in a BoingBoing article on fetal senses. Long story short: Kittens are born blind and do a lot of their sight-linked brain development in the first few weeks after birth. Because of this, they make a handy model for studying how the brains of human fetuses form neural connections and how our sense of sight develops in the womb. It's important research that has helped medical science better understand how to care for premature human babies, besides adding valuable details to our understanding of the brain, in general.

Unfortunately, because kittens are adorable, said very important research looks almost comically evil when filmed. Seriously, this video is one "Thittens" joke away from working as a segment of Look Around You.

So, thanks, blorgggg (Thorgggg?), for sending this video in via Submitterator. I'm sure the Moderators will be thanking you (and me) as well. I do ask that, as we get into the inevitable discussion on animal research, you remember that the scientists involved did not raise kittens in completely dark rooms for sociopathic shits and giggles, but because they thought the potential benefits of the research outweighed the (mostly temporary) damage done to the kittens' visual abilities. You may disagree with that calculation—and you're welcome to do so. In fact, I think that complex discussion about ends and means in specific studies is valuable. And interesting. Far more so (on both counts) than simply labeling anyone who uses animals for research as a for-kicks abuser of fluffy baby kitties.

 

 

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How neuroscience will change our view on consciousness

Victor Lamme on consciousness.

 

 

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How neuroscience will change our view on consciousness

via : Articles recently published in by Lamme, Victor A. F. on 9/3/10

 

 

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Reading between the Lines: How We See Hidden Objects

About amodal completion.

 

 

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Reading between the Lines: How We See Hidden Objects

via Scientific American on 8/30/10

Imagine that you are looking at a dog that is standing behind a picket fence. You do not see several slices of dog; you see a single dog that is partially hidden by a series of opaque vertical slats. The brain's ability to join these pieces into a perceptual whole demonstrates a fascinating process known as amodal completion.

It is clear why such a tendency would have evolved. Animals must be able to spot a mate, predator or prey through dense foliage. The retinal image may contain only fragments, but the brain's visual system links them, reconstructing the object so the animal can recognize what it sees. The process seems effortless to us, but it has turned out to be one of those things that is horrendously difficult to program computers to do. Nor is it clear how neurons in the brain's visual pathways manage the trick.

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Neuron - Brain - Dog - Biology - Animal

 

 

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Gestalt Principles Applied in Design

From today's Delicious hotlist.

 

 

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Gestalt Principles Applied in Design

via Delicious hotlist by ani625 on 8/17/10

 Bookmark this on Delicious - Saved by ani625 to design gestalt webdesign psychology principles ui theory article blog reference - More about this bookmark

 

 

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