Kenneth Hugdahl

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Humans engaged in monotonous tasks are susceptible to occasional errors that may lead to serious consequences, but little is known about brain activity patterns preceding errors. Using functional MRI and applying independent component analysis followed by deconvolution of hemodynamic responses, we studied error preceding brain activity on a trial-by-trial(More)
The brain acts as an integrated information processing system, which methods in cognitive neuroscience have so far depicted in a fragmented fashion. Here, we propose a simple and robust way to integrate functional MRI (fMRI) with single trial event-related potentials (ERP) to provide a more complete spatiotemporal characterization of evoked responses in the(More)
The present study was concerned with the effects of directional attention on the right-ear-advantage (REA) in dichotic listening. It was suggested that if selective attention contributes to the REA during a non-forced, free recall condition, then comparing the unattended left and right ear scores when attention is forced to the right and the left ear,(More)
The main purpose of the present study was to: 1) to investigate differences between males and females in brain activation when performing a mental rotation task, 2) investigate hemisphere differences in brain activation during mental rotation. Brain activation was measured with functional magnetic resonance imaging (fMRI). Image acquisition was performed(More)
CONTEXT Limbic structures are implicated in the genesis of attention-deficit/hyperactivity disorder (ADHD) by the presence of mood and cognitive disturbances in affected individuals and by elevated rates of mood disorders in family members of probands with ADHD. OBJECTIVE To study the morphology of the hippocampus and amygdala in children with ADHD. (More)
Dichotic listening means that two different stimuli are presented at the same time, one in each ear. This technique is frequently used in experimental and clinical studies as a measure of hemispheric specialization. The primary aim of the present study was to record regional changes in the distribution of cerebral blood flow (CBF) with the 15O-PET technique(More)
Following the theoretical framework of coordinate and categorical principals for visuo-spatial processing, originally formulated by [Kosslyn, S. M. (1987). Seeing and imagining in the cerebral hemispheres: AQ computational approach. Psychological Review, 94, 148-175], we present data from an fMRI study on mental rotation, using the classic [Shepard, R. N.,(More)
The aim of this study was to establish the rate of progression from mild cognitive impairment (MCI) to dementia in patients with Parkinson's disease (PD). PD patients without dementia were recruited in 1997 from an ongoing prospective epidemiological study. The assessment included neurological and psychiatric examinations, a clinical interview based on the(More)
To investigate the hypothesis of a right hemispheric superiority in negative emotional processing, event-related potentials (ERPs) were recorded from 17 sites (Fz, Cz, Pz, F3/4, F7/8, C3/4, T7/8, P3/4, P7/8, O1/2) in a visual half-field paradigm. While maintaining fixation, right-handed women viewed pictures of patients with dermatological diseases before(More)
In this article we present a theoretical approach to cognitive control and attention modulation, as well as review studies related to such a view, using an auditory task based on dichotic presentations of simple consonant-vowel syllables. The reviewed work comes out of joint research efforts by the 'Attention-node' at the 'Nordic Center of Excellence in(More)