Research Interests:
Phonetics, Attention, Electroencephalography, Brain and Cognitive Development, Language, and 15 moreAdolescent, Memory, Brain, Humans, Change detection, Female, Male, Mismatch Negativity, Adult, Auditory Cortex, Auditory Sensory Memory, Native Speaker, Boundary Effect, Contingent Negative Variation, and Acoustic Stimulation
Research Interests:
Psychology, Psychophysiology, Auditory Perception, Magnetoencephalography, Attention, and 13 moreMedicine, Biological Sciences, Humans, Female, Male, Pitch Perception, Mismatch Negativity, Adult, Auditory Cortex, Functional Laterality, Acoustic Stimulation, Psychology and Cognitive Sciences, and Medical and Health Sciences
Research Interests:
Research Interests:
An increasing number of studies have addressed how adolescents’ social media use is associated with depressive symptoms. However, few studies have examined whether these links occur longitudinally across adolescence when examined at the... more
An increasing number of studies have addressed how adolescents’ social media use is associated with depressive symptoms. However, few studies have examined whether these links occur longitudinally across adolescence when examined at the individual level of development. This study investigated the within-person effects between active social media use and depressive symptoms using a five-wave longitudinal dataset gathered from 2891 Finnish adolescents (42.7% male, age range 13–19 years). Sensitivity analysis was conducted, adjusting for gender and family financial status. The results indicate that depressive symptoms predicted small increases in active social media use during both early and late adolescence, whereas no evidence of the reverse relationship was found. Yet, the associations were very small, statistically weak, and somewhat inconsistent over time. The results provide support for the growing notion that the previously reported direct links between social media use and depr...
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Research Interests:
Dual language experience has typically been shown to improve various executive control functions. We investigated with event-related brain potentials (ERPs) recorded from early (natively) bilingual speakers and control participants... more
Dual language experience has typically been shown to improve various executive control functions. We investigated with event-related brain potentials (ERPs) recorded from early (natively) bilingual speakers and control participants whether it also affects auditory selective attention. We delivered to our participants two tone streams, one to the left and one to the right ear. Both streams consisted of standard tones and two types of infrequent deviant tones which had either an enhanced duration or intensity. The participants were instructed to attend either to the right or left stream and to detect longer-duration deviants in the attended stream. The results showed that the early bilinguals did not outperform the controls in target detection accuracy or speed. However, the late portion of the attention-related ERP modulation (the negative difference, Nd) was larger over the left hemisphere in the early bilinguals than in the controls, suggesting that the maintenance of selective att...
Research Interests:
Research Interests:
Individuals with prolonged occupational stress often report difficulties in concentration. Work tasks often require the ability to switch back and forth between different contexts. Here, we studied the association between job burnout and... more
Individuals with prolonged occupational stress often report difficulties in concentration. Work tasks often require the ability to switch back and forth between different contexts. Here, we studied the association between job burnout and task switching by recording event-related potentials (ERPs) time-locked to stimulus onset during a task with simultaneous cue-target presentation and unpredictable switches in the task. Participants were currently working people with severe, mild, or no burnout symptoms. In all groups, task performance was substantially slower immediately after task switch than during task repetition. However, the error rates were higher in the severe burnout group than in the mild burnout and control groups. Electrophysiological data revealed an increased parietal P3 response for the switch trials relative to repetition trials. Notably, the response was smaller in amplitude in the severe burnout group than in the other groups. The results suggest that severe burnou...
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In the present article, the basic research using the mismatch negativity (MMN) and analogous results obtained by using the magnetoencephalography (MEG) and other brain-imaging technologies is reviewed. This response is elicited by any... more
In the present article, the basic research using the mismatch negativity (MMN) and analogous results obtained by using the magnetoencephalography (MEG) and other brain-imaging technologies is reviewed. This response is elicited by any discriminable change in auditory stimulation but recent studies extended the notion of the MMN even to higher-order cognitive processes such as those involving grammar and semantic meaning. Moreover, MMN data also show the presence of automatic intelligent processes such as stimulus anticipation at the level of auditory cortex. In addition, the MMN enables one to establish the brain processes underlying the initiation of attention switch to, conscious perception of, sound change in an unattended stimulus stream.
Research Interests:
Engineering, Perception, Brain Imaging, Electrophysiology, Auditory Perception, and 15 moreMagnetoencephalography, Attention, Evoked Potentials, Humans, Cerebral Cortex, Auditory Processing, Animals, Anticipation, Cognitive Process, Mismatch Negativity, Clinical Neurophysiology, Basic Research, Auditory Cortex, Pitch discrimination, and Medical and Health Sciences
Research Interests:
Research Interests:
We describe, for the first time, the use of high-resolution event-related brain potentials (hrERP) to identify the spatio-temporal characteristics of neural systems involved in phonological analysis. Subjects studied a visual... more
We describe, for the first time, the use of high-resolution event-related brain potentials (hrERP) to identify the spatio-temporal characteristics of neural systems involved in phonological analysis. Subjects studied a visual word/non-word that was followed by the brief presentation of a prime letter (e.g. House, M) with the instruction to anticipate the word/non-word formed by replacing the word's first letter with the prime letter. After the prime letter, an auditory target word/non-word was presented that either matched/mismatched expectations (e.g., Mouse/Barn). ERPs were recorded to the onset of the auditory targets and scalp topographical maps were derived for the phonological mismatch negativity (PMN). The PMN reflected phonological analysis and examination of the peak topography revealed that the response was characterized by a prominent frontal, right-asymmetrical distribution. Spatial de-blurring (using current source density maps) indicated that the PMN scalp topography resulted primarily from an active left anterior source. The current results provide the initial evidence for the localization of the intra-cranial generator(s) involved in phonological analysis.
Research Interests:
Cognitive Science, Phonology, Electrophysiology, Phonetics, Cognition, and 15 moreMagnetoencephalography, Electroencephalography, Language, Brain Mapping, Humans, Cerebral Cortex, Female, Male, High Resolution, Adult, Priming effect, Auditory evoked Potentials, Neurosciences, Acoustic Stimulation, and photic stimulation
ERPs to sequences of standard and deviant sinusoidal 100 msec tone pips, high-contrast sinusoidal gratings and to their simultaneously presented combinations were recorded. Mismatch negativity (MMN), an ERP component elicited by deviant... more
ERPs to sequences of standard and deviant sinusoidal 100 msec tone pips, high-contrast sinusoidal gratings and to their simultaneously presented combinations were recorded. Mismatch negativity (MMN), an ERP component elicited by deviant stimuli, was estimated for the different stimulus sequences in order to find out whether it reflects modality-specific processes or non-specific attentive phenomena. In addition to the auditory modality, we studied whether the mismatch response could be evoked by a deviant visual stimulus in a visual sequence or by a deviant stimulus in either modality. The results show that only auditory stimuli produced the mismatch response, suggesting that MMN is not a manifestation of a general attentional mechanism but is probably specific to the auditory modality.
Research Interests:
Deviant tones randomly embedded in a sequence of standard tones elicit an event-related potential (ERP) called the mismatch negativity (MMN), which reflects automatic stimulus-change detection in the human auditory system. When the tones... more
Deviant tones randomly embedded in a sequence of standard tones elicit an event-related potential (ERP) called the mismatch negativity (MMN), which reflects automatic stimulus-change detection in the human auditory system. When the tones are attended, deviant tones elicit also an N2b component that partly overlaps the MMN. Sequences of standard and deviant (probability 0.15) tones were presented to 13 healthy younger and 13 older subjects. Deviant stimuli were, in separate blocks, either occasional shorter duration or higher frequency tones. The interstimulus interval (ISI) was, in separate blocks, either 0.5 s or 1.5 s, and in the frequency-change condition also 4.5 s. Aging affected neither frequency nor duration of MMN with the 0.5 s ISI. This finding indicates that automatic stimulus discrimination per se is not impaired with normal aging. However, with a 4.5-s ISI the MMN/N2b-complex attenuated significantly more in the older than younger subjects. This suggests that the stimulus trace decays faster or that involuntary attention switching is less sensitive with aging.
Research Interests:
Electrophysiology, Auditory Perception, Cognition, Aging, Adolescent, and 15 moreInformation Processing, Evoked Potentials, Humans, Change detection, Auditory Processing, Female, Male, Clinical Sciences, Mismatch Negativity, Aged, Middle Aged, Adult, Age effect, Acoustic Stimulation, and human auditory system
Research Interests:
Physically deviant auditory stimuli occurring among frequent ("standard") stimuli (e.g., tones or phonetic stimuli) elicit the mismatch negativity (MMN) of the auditory event-related potential (ERP). The MMN is... more
Physically deviant auditory stimuli occurring among frequent ("standard") stimuli (e.g., tones or phonetic stimuli) elicit the mismatch negativity (MMN) of the auditory event-related potential (ERP). The MMN is presumably generated by a mismatch process between the sensory input from a deviant stimulus and a neural sensory-memory trace representing the physical features of the standard stimulus. This process, as well as sensory analysis of auditory input and its encoding into the memory trace, appear to be automatic since the MMN is elicited even by changes in unattended auditory stimuli. Therefore the MMN indirectly provides a unique, objective measure of the central representation of a sound. This opens new possibilities for basic research as well as clinical and other applications.
Research Interests:
Event-related potentials (ERPs) were recorded in subjects receiving tones (left ear 300 Hz, right ear 6000 Hz) at a rapid rate and trying to detect occasional higher-pitched stimuli in a designated ear. ERPs to attended stimuli showed... more
Event-related potentials (ERPs) were recorded in subjects receiving tones (left ear 300 Hz, right ear 6000 Hz) at a rapid rate and trying to detect occasional higher-pitched stimuli in a designated ear. ERPs to attended stimuli showed enhanced negative amplitudes whose topographical distribution differed from that of the exogeneous N1 component. Moreover, the latter was considerably larger for low than high tones, whereas the attention effect had similar amplitudes for the two tones. Consequently, the attention effect, even when perfectly coinciding in time with N1, does not seem to be caused by modulation of the exogeneous N1 but rather by a separate process activated by attention. This suggests that attention does not modulate initial stimulus representations in audition.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Abstract Event-related potentials (ERPs) to a change in the locus of origin of a repetitive sound were studied in early blind human subjects. It was found that the N2b component of the ERP was posteriorly distributed on the scalp to that... more
Abstract Event-related potentials (ERPs) to a change in the locus of origin of a repetitive sound were studied in early blind human subjects. It was found that the N2b component of the ERP was posteriorly distributed on the scalp to that in the sighted control subjects. This ...
Research Interests:
Research Interests:
Regional cerebral blood flow (rCBF) was measured with positron emission tomography (PET) while subjects were selectively listening to continuous speech delivered to one ear and ignoring concurrent speech delivered to the opposite ear, as... more
Regional cerebral blood flow (rCBF) was measured with positron emission tomography (PET) while subjects were selectively listening to continuous speech delivered to one ear and ignoring concurrent speech delivered to the opposite ear, as well as concurrent text or letter strings running on a screen. rCBF patterns associated with selective listening either to the left-ear or right-ear speech message were compared with each other and with rCBF patterns in two visual-attention conditions in which the subjects ignored both speech messages and either read the text or discriminated the meaningless letter strings moving on the screen. Attention to either speech message was associated with enhanced activity in the superior temporal cortex of the language-dominant left hemisphere, as well as in the superior and middle temporal cortex of the right hemisphere suggesting enhanced processing of prosodic features in the attended speech. Moreover, enhanced activity during attention to either speech message was observed in the right parietal areas known to have an important role in directing spatial attention. Evidence was also found for attentional tuning of the left and right auditory cortices to select information from the contralateral auditory hemispace.
Research Interests:
Nonparametric Statistics, Attention, Brain and Cognitive Development, Adolescent, Positron Emission Tomography, and 15 morePET, Brain Mapping, Brain, Humans, Male, Adult, Analysis of Variance, Regional Cerebral Blood Flow, Auditory Cortex, Left Hemisphere, Cerebral Blood Flow, Functional Laterality, Acoustic Stimulation, photic stimulation, and Dichotic Listening tests
Research Interests:
Research Interests:
Auditory Perception, Speech perception, Attention, Electroencephalography, Brain and Cognitive Development, and 12 moreSpeech Processing, Evoked Potentials, Humans, Change detection, Female, Male, Mismatch Negativity, Adult, Auditory evoked Potentials, Electrooculography, Temporal Change, and Acoustic Stimulation
Research Interests:
Event-related potentials (ERPs) were recorded in subjects receiving tones (left ear 300 Hz, right ear 6000 Hz) at a rapid rate and trying to detect occasional higher-pitched stimuli in a designated ear. ERPs to attended stimuli showed... more
Event-related potentials (ERPs) were recorded in subjects receiving tones (left ear 300 Hz, right ear 6000 Hz) at a rapid rate and trying to detect occasional higher-pitched stimuli in a designated ear. ERPs to attended stimuli showed enhanced negative amplitudes whose topographical distribution differed from that of the exogeneous N1 component. Moreover, the latter was considerably larger for low than high tones, whereas the attention effect had similar amplitudes for the two tones. Consequently, the attention effect, even when perfectly coinciding in time with N1, does not seem to be caused by modulation of the exogeneous N1 but rather by a separate process activated by attention. This suggests that attention does not modulate initial stimulus representations in audition.
Research Interests:
We describe, for the first time, the use of high-resolution event-related brain potentials (hrERP) to identify the spatio-temporal characteristics of neural systems involved in phonological analysis. Subjects studied a visual... more
We describe, for the first time, the use of high-resolution event-related brain potentials (hrERP) to identify the spatio-temporal characteristics of neural systems involved in phonological analysis. Subjects studied a visual word/non-word that was followed by the brief presentation of a prime letter (e.g. House, M) with the instruction to anticipate the word/non-word formed by replacing the word's first letter with the prime letter. After the prime letter, an auditory target word/non-word was presented that either matched/mismatched expectations (e.g., Mouse/Barn). ERPs were recorded to the onset of the auditory targets and scalp topographical maps were derived for the phonological mismatch negativity (PMN). The PMN reflected phonological analysis and examination of the peak topography revealed that the response was characterized by a prominent frontal, right-asymmetrical distribution. Spatial de-blurring (using current source density maps) indicated that the PMN scalp topography resulted primarily from an active left anterior source. The current results provide the initial evidence for the localization of the intra-cranial generator(s) involved in phonological analysis.
Research Interests:
Cognitive Science, Phonology, Electrophysiology, Phonetics, Cognition, and 15 moreMagnetoencephalography, Electroencephalography, Language, Brain Mapping, Humans, Cerebral Cortex, Female, Male, High Resolution, Adult, Priming effect, Auditory evoked Potentials, Neurosciences, Acoustic Stimulation, and photic stimulation
Research Interests:
Magnetic Resonance Imaging, Attention, Linear models, Brain Mapping, Humans, and 13 moreCerebral Cortex, Segmentation, Female, Neuroimage, Male, Reaction Time, Image Enhancement, Adult, Auditory Cortex, Psychomotor Performance, Psychology and Cognitive Sciences, Pitch discrimination, and Medical and Health Sciences
An event-related brain potential (ERP) component called mismatch negativity (MMN) is elicited by physically deviant auditory stimuli presented among repetitive, "standard," stimuli. MMN reflects a mismatch process between... more
An event-related brain potential (ERP) component called mismatch negativity (MMN) is elicited by physically deviant auditory stimuli presented among repetitive, "standard," stimuli. MMN reflects a mismatch process between sensory input from the deviant stimulus and a shortduration neuronal representation developed by the standard stimulus. The MMN amplitude is known to correlate with pitch-discrimination performance. The purpose of the present study was to investigate whether the MMN is different in absolute pitch (AP) possessors and nonpossessors. ERPs were recorded from AP and non-AP groups, which were matched with regard to musical training. It was found that deviant stimuli differing from standard tones by a quartertone or a semitone elicited an MMN irrespective of whether the stimulus was located on (white key/black key) or off the Western musical scale. These results were obtained with both sinusoidal and piano tones. The MMN was larger and earlier when the stimuli w...
Research Interests:
Research Interests:
The mismatch negativity (MMN), elicited by any discriminable change in a repetitive sound even when this sound is not attended to, provides a pre-perceptual physiological measure of the accuracy of the central sound representation in the... more
The mismatch negativity (MMN), elicited by any discriminable change in a repetitive sound even when this sound is not attended to, provides a pre-perceptual physiological measure of the accuracy of the central sound representation in the human brain. This accuracy, which can be measured separately for the different features of the sound, determines the individual's sound discrimination accuracy in normal and various pathological conditions.
Research Interests:
Modern environments are full of information, and place high demands on the attention control mechanisms that allow the selection of information from one (focused attention) or multiple (divided attention) sources, react to changes in a... more
Modern environments are full of information, and place high demands on the attention control mechanisms that allow the selection of information from one (focused attention) or multiple (divided attention) sources, react to changes in a given situation (stimulus-driven attention), and allocate effort according to demands (task-positive and task-negative activity). We aimed to reveal how attention deficit hyperactivity disorder (ADHD) affects the brain functions associated with these attention control processes in constantly demanding tasks. Sixteen adults with ADHD and 17 controls performed adaptive visual and auditory discrimination tasks during functional magnetic resonance imaging (fMRI). Overlapping brain activity in frontoparietal saliency and default-mode networks, as well as in the somato-motor, cerebellar, and striatal areas were observed in all participants. In the ADHD participants, we observed exclusive activity enhancement in the brain areas typically considered to be pri...