WITHDRAWN: Anticonvulsant drugs for migraine prophylaxis.

July 2015: This review has been split and updated in a series of four new reviews (Linde 2013a; Linde 2013b; Linde 2013c; Linde 2013d). Readers are referred to those reviews for updated results. This review will not be updated.

Valproate (valproic acid or sodium valproate or a combination of the two) for the prophylaxis of episodic migraine in adults.

Background: Some antiepileptic drugs but not others are useful in clinical practice for the prophylaxis of migraine. This might be explained by the variety of actions of these drugs in the central nervous system. The present review is part of an update of a Cochrane review first published in 2004, and previously updated (conclusions not changed) in 2007.

Topiramate for the prophylaxis of episodic migraine in adults.

Background: Some antiepileptic drugs but not others are useful in clinical practice for the prophylaxis of migraine. This might be explained by the variety of actions of these drugs in the central nervous system. The present review is part of an update of a Cochrane review first published in 2004, and previously updated (conclusions not changed) in 2007.

Gabapentin or pregabalin for the prophylaxis of episodic migraine in adults.

Background: Some antiepileptic drugs but not others are useful in clinical practice for the prophylaxis of migraine. This might be explained by the variety of actions of these drugs in the central nervous system. The present review is part of an update of a Cochrane review first published in 2004, and previously updated (conclusions not changed) in 2007.

Antiepileptics other than gabapentin, pregabalin, topiramate, and valproate for the prophylaxis of episodic migraine in adults.

Background: Some antiepileptic drugs but not others are useful in clinical practice for the prophylaxis of migraine. This might be explained by the variety of actions of these drugs in the central nervous system. The present review is part of an update of a Cochrane review first published in 2004, and previously updated (conclusions not changed) in 2007.

Act first, think later: the presence and absence of inferential planning in problem solving.

Planning is fundamental to successful problem solving, yet individuals sometimes fail to plan even one step ahead when it lies within their competence to do so. In this article, we report two experiments in which we explored variants of a ball-weighing puzzle, a problem that has only two steps, yet nonetheless yields performance consistent with a failure to plan. The results fit a computational model in which a solver's attempts are determined by two heuristics: maximization of the apparent progress made toward the problem goal and minimization of the problem space in which attempts are sought.

Functional imaging studies in cannabis users.

Cannabis remains the most widely used illegal drug in the United States. This update examines the available literature on neuroimaging studies of the brains of cannabis users. The majority of studies examining the acute effects of delta-9-tetrahydrocannabinol (THC) administration used PET methods and concluded that administration of THC leads to increased activation in frontal and paralimbic regions and the cerebellum.

It looks easy! Heuristics for combinatorial optimization problems.

Human performance on instances of computationally intractable optimization problems, such as the travelling salesperson problem (TSP), can be excellent. We have proposed a boundary-following heuristic to account for this finding. We report three experiments with TSPs where the capacity to employ this heuristic was varied.

Premorbid childhood ocular alignment abnormalities and adult schizophrenia-spectrum disorder.

This study examined the relation between childhood ocular alignment deficits and adult psychiatric outcomes among children at high-risk for schizophrenia and controls. A sample of 265 Danish children was administered a standardized eye exam assessing strabismus and related ocular alignment deficits. All children whose mothers or fathers had a psychiatric diagnosis of schizophrenia comprised the first group (N=90).

Assessing cortical excitability in migraine: reliability of magnetic suppression of perceptual accuracy technique over time.

Objectives: To examine test-retest reliability of magnetic suppression of perceptual accuracy (MSPA) prior to its use as a marker of cortical excitability in a trial of migraine prophylactic agents.

Background: MSPA is a relatively novel avenue of research in headache, providing an opportunity to study cortical responsiveness objectively and noninvasively. However, little is known about the reliability of magnetic stimulation protocols such as MSPA in longitudinal research designs.

Cortical inhibition is reduced in chronic and episodic migraine and demonstrates a spectrum of illness.

Background: The pathophysiological relationship between episodic migraine and chronic migraine is not fully understood. We aimed to examine transcranial magnetic stimulation (TMS) indices of cortical excitability in patients with episodic migraine (EM) and probable chronic migraine (PCM), and matched controls.

Methods: Cortical excitability was assessed at baseline with two well-established methods: phosphene thresholds (PT) and magnetic suppression of perceptual accuracy (MSPA) profiles.

Development and positioning reliability of a TMS coil holder for headache research.

Objective: Accurate and reproducible coil positioning is important for headache research using transcranial magnetic stimulation protocols. We aimed to design a transcranial magnetic stimulation coil holder and demonstrate reliability of test-retest coil positioning.

Methods: A coil holder was developed and manufactured according to three principles of stability, durability, and three-dimensional positional accuracy.

Convex hull or crossing avoidance? Solution heuristics in the traveling salesperson problem.

Untrained adults appear to have access to cognitive processes that allow them to perform well in the Euclidean version of the traveling salesperson problem (E-TSP). They do so despite the famous computational intractability of the problem, which stems from its combinatorial complexity. A current hypothesis is the humans' good performance is based on following a strategy of connecting boundary points in order (the convex hull hypothesis).

What makes an insight problem? The roles of heuristics, goal conception, and solution recoding in knowledge-lean problems.

Four experiments investigated transformation problems with insight characteristics. In Experiment 1, performance on a version of the 6-coin problem that had a concrete and visualizable solution followed a hill-climbing heuristic. Experiment 2 demonstrated that the difficulty of a version of the problem that potentially required insight for solution stems from the same hill-climbing heuristic, which creates an implicit conceptual block.

The role of pictorial convention in haptic picture perception.

An investigation of tactile picture perception is reported. Blindfolded sighted subjects explored either 'line drawings' or 'textured' tactile pictures produced on Zytex swell paper. All pictures were 'two-dimensional', that is they depicted only one object face and so did not represent a third dimension.

A ticklish question: does magnetic stimulation of the primary motor cortex give rise to an 'efference copy'?

In order to make accurate predictions about the somatosensory consequences of our own movements, an 'efference copy' of motor output appears to be used (probably in the cerebellum) as a basis for anticipating and canceling incoming information about self-produced movement. One everyday phenomenon that results from these predictive processes is that of being unable to tickle oneself. We examined whether involuntary movements induced by magnetic stimulation of (a) the motor cortex and (b) the bicep muscle, both resulting in standard stimulation of the participant's bare foot, would be perceived as ticklish.

Dynamics and constraints in insight problem solving.

This article reports 2 experiments that investigated performance on a novel insight problem, the 8-coin problem. The authors hypothesized that participants would make certain initial moves (strategic moves) that seemed to make progress according to the problem instructions but that nonetheless would guarantee failure to solve the problem. Experiment 1 manipulated the starting state of the problem and showed that overall solution rates were lower when such strategic moves were available.