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Objective: The aim of the current study was to examine whether and to what extent mood disorders, comprising major depression and bipolar disorder, are accompanied by structural changes in the brain as measured using voxel-based morphometry (VBM)., Methods: We performed a VBM study using a 3Т MRI system (GE Discovery 750w) in patients with mood disorders (n=50), namely, 39 with major depression and 11 with bipolar disorder compared to 42 age-, sex- and education-matched healthy controls., Results: Our results show that depression was associated with significant decreases in grey matter (GM) volume of the regions located within the medial frontal and anterior cingulate cortex on the left side and middle frontal gyrus, medial orbital gyrus, inferior frontal gyrus (triangular and orbital parts) and middle temporal gyrus (extending to the superior temporal gyrus) on the right side. When the patient group was separated into bipolar disorder and major depression, the reductions remained significant only for patients with major depressive disorder., Conclusions: Using VBM the present study was able to replicate decreases in GM volume restricted to frontal and temporal regions in patients with mood disorders, mainly major depression, compared with healthy controls.

Persons with Parkinson's disease have general timing deficits and have difficulties in rhythm discrimination tasks. The basal ganglia, a crucial part of Parkinson's disease pathology, is believed to play an important role in rhythm and beat processing, with a possible modulation of basal ganglia activity by level of rhythmic complexity. As dysfunction in basal ganglia impacts function in other brain areas in Parkinson's disease during temporal processing, investigating the neuronal basis for rhythm processing is important as it could shed light on the nature of basal ganglia dysfunction and compensatory mechanisms. We constructed an auditory beat-omission fMRI paradigm with two levels of rhythm complexity, to investigate if and where persons with Parkinson's disease showed abnormal activation during rhythm and omission processing, and whether such activations were modulated by the level of rhythmic complexity. We found no effect of complexity, but found crucial group differences. For the processing of normal rhythm presentations, the Parkinson-group showed higher bilateral planum temporal activity, an area previously associated with the processing of complex patterns. For the omissions, the Parkinson-group showed higher activity in an area in the right superior temporal gyrus previously associated with detection of auditory omissions. We believe this shows a pattern of "hypersensitive" activity, indicative of task-specific, compensatory mechanisms in the processing of temporal auditory information in persons with Parkinson's disease.

The superior temporal sulcus (STS) is an anatomical structure that increasingly interests researchers. This structure appears to receive multisensory input and is involved in several perceptual and cognitive core functions, such as speech perception, audiovisual integration, (biological) motion processing and theory of mind capacities. In addition, the superior temporal sulcus is not only one of the longest sulci of the brain, but it also shows marked functional and structural asymmetries, some of which have only been found in humans. To explore the functional-structural relationships of these asymmetries in more detail, this study combines functional and structural magnetic resonance imaging. Using a speech perception task, an audiovisual integration task, and a theory of mind task, this study again demonstrated an involvement of the STS in these processes, with an expected strong leftward asymmetry for the speech perception task. Furthermore, this study confirmed the earlier described, human-specific asymmetries, namely that the left STS is longer than the right STS and that the right STS is deeper than the left STS. However, this study did not find any relationship between these structural asymmetries and the detected brain activations or their functional asymmetries. This can, on the other hand, give further support to the notion that the structural asymmetry of the STS is not directly related to the functional asymmetry of the speech perception and the language system as a whole, but that it may have other causes and functions., (© 2018 The Authors. Scandinavian Journal of Psychology published by Scandinavian Psychological Associations and John Wiley & Sons Ltd.)

Mismatch negativity (MMN), an ERP elicited by a deviant stimulus in a train of standard stimuli, has been suggested to be associated to glutamatergic neurotransmission, mediated by glutamatergic NMDA receptors. In this study, we examined the relationship between interindividual variation of (1)H-MRS-measured glutamate+glutamine (Glx) in the superior temporal gyrus and MMN for duration and frequency deviants in 19 healthy young adults (9 male). We found a significant relationship between the peak latency of the duration-MMN peak and creatine-scaled Glx (p = .0003, η(2)  = .43), with increased Glx level being associated to earlier peak of the duration-MMN (r = -.63). In contrast, the amplitude of the duration-MMN was not related to Glx. There was no significant relationship between Glx and the frequency-MMN. The present study is the first to demonstrate that interindividual variation in the glutamatergic neurotransmission affects the MMN response in healthy individuals., (© 2015 Society for Psychophysiological Research.)

It has previously been shown that task performance and frontal cortical activation increase after cognitive conflict. This has been argued to support a model of attention where the level of conflict automatically adjusts the amount of cognitive control applied. Conceivably, conflict could also modulate lower-level processing pathways, which would be evident as trial-to-trial changes in domain specific activation. The present fMRI experiment used a syllable identification task where conflict is manipulated by presenting recently ignored syllables. Results showed that on trials following a high conflict trial, activation increased primarily in the planum temporale region of the left temporal cortex, an area believed to be involved in syllable discrimination. The experiment thus showed a transient, domain specific attention effect that was modulated on a trial-to-trial basis. We argue that this indicates a self-regulating system where increased levels of conflict directs resources in order to improve performance., (Copyright © 2011 Elsevier Inc. All rights reserved.)

A common assumption is that phonetic sounds initiate unique processing in the superior temporal gyri and sulci (STG/STS). The anatomical areas subserving these processes are also implicated in the processing of non-phonetic stimuli such as music instrument sounds. The differential processing of phonetic and non-phonetic sounds was investigated in this study by applying a "sound-morphing" paradigm, where the presence of phonetic features were parametrically varied, creating a step-wise transition from a non-phonetic sound into a phonetic sound. The stimuli were presented in an event-related fMRI design. The fMRI-BOLD data were analysed using parametric contrasts. The results showed a higher sensitivity for sounds containing phonetic features compared to non-phonetic sounds in the middle part of STG, and in the anterior part of the planum temporale (PT) bilaterally. Although the same areas were involved in the processing of non-phonetic sounds, a difference in activation was evident in the STG, with an increase in activation related to increment of phonetic features in the sounds. The results indicate a stimulus-driven, bottom-up process that utilizes general auditory resources in the secondary auditory cortex, depending on specific phonetic features in the sounds., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Attention deficit/hyperactivity disorder (ADHD) is characterized by widespread structural and functional abnormalities in the brain. We applied different structural imaging techniques such as voxel-based morphometry (VBM), diffusion tensor imaging (DTI), and magnetization transfer imaging (MTI) to study anatomical differences between boys with ADHD and healthy controls, as well as functional magnetic resonance imaging (fMRI) together with independent component analysis (ICA) to detect functional alterations. 14 boys with ADHD and 12 controls were included in our study. Results of DTI showed the expected differences in frontal and cerebellar white matter. VBM and MTI indicated group differences in the temporal lobe. Applying ICA to fMRI data, we extracted four components; two positively correlated to our working memory paradigm and two negatively correlated. Positive components included activation in frontal and parietal regions. Negative components showed activation in anterior and posterior cingulate cortex/precuneus and temporal regions, and were interpreted as forming part of the default mode network. Group differences in the inferior temporal lobe were detected. Applying different techniques, we found differences between boys with ADHD and controls mainly located in the temporal lobe. Therefore, we postulate that research on ADHD should broaden its scope by including the temporal lobe as a potentially important locus of abnormalities in ADHD., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Contrary to the classical view, recent neuroimaging studies claim that phonological processing, as part of auditory speech perception, is subserved by both the left and right temporal lobes and not the left temporal lobe alone. This study seeks to explore whether there are variations in the lateralization of response to verbal and nonverbal sounds by varying spectral complexity of those sounds. White noise was gradually transformed into either speech or music sounds using a "sound morphing" procedure. The stimuli were presented in an event-related design and the evoked brain responses were measured using fMRI. The results demonstrated that the left temporal lobe was predominantly sensitive to gradual manipulation of the speech sounds while the right temporal lobe responded to all sounds and manipulations. This effect was especially pronounced within the middle region of the left superior temporal sulcus (mid-STS). This area could be further subdivided into a more posterior area, which showed a linear response to the manipulation of speech sounds, and an anteriorly adjacent area which showed the strongest interaction between the speech and music sound manipulations. Such a differential and selective response was not seen in other brain areas and not when the sound "morphed" into a music stimulus. This gives further experimental evidence for the assumption of a posterior-anterior processing stream in the left temporal lobe. In addition, the present findings support the notion that the left mid STS area is more sensitive to speech signals compared to the right homologue.

The midsagittal corpus callosum is topographically organized, that is, with regard to their cortical origin several subtracts can be distinguished within the corpus callosum that belong to specific functional brain networks. Recent diffusion tensor tractography studies have also revealed remarkable interindividual differences in the size and exact localization of these tracts. To examine the functional relevance of interindividual variability in callosal tracts, 17 right-handed male participants underwent structural and diffusion tensor magnetic resonance imaging. Probabilistic tractography was carried out to identify the callosal subregions that interconnect left and right temporal lobe auditory processing areas, and the midsagittal size of this tract was seen as indicator of the (anatomical) strength of this connection. Auditory information transfer was assessed applying an auditory speech perception task with dichotic presentations of consonant-vowel syllables (e.g., /ba-ga/). The frequency of correct left ear reports in this task served as a functional measure of interhemispheric transfer. Statistical analysis showed that a stronger anatomical connection between the superior temporal lobe areas supports a better information transfer. This specific structure-function association in the auditory modality supports the general notion that interindividual differences in callosal topography possess functional relevance.

Recent models of speech processing claim a ventral and dorsal stream for processing language as for the visual domain. Patients with aphasia are demonstrating selective disturbances within parts of these streams. Here, we are presenting an fMRI study, which mainly focuses on the ventral stream, i.e. the phonological, lexical, and semantic processing of auditory speech. We used three linguistic conditions: (1) listening to reversed words, (2) listening to real words and, (3) covert naming after short description. We analysed the temporal dynamics of the BOLD signal as well as the temporal dynamics of lateralisation. In addition, an independent component analysis (ICA) was applied. By combining the results from these methods, we were able to separate the areas for pure auditory-phonetic perception, located bilaterally in the middle and posterior aspects of the superior temporal lobe, from predominantly left-lateralised areas for semantic and lexical processing, located in posterior-inferior as well as anterior regions of the temporal lobe, at the temporal-parietal-junction, and in the inferior frontal gyrus. These two networks differed with respect to their time course and temporal dynamics of lateralisation, and they were separated into two components of the ICA analysis. By being able to separate these two networks, we further conclude that this complementary analysis method might also be relevant for exploring recovery processes in patients with aphasia.

Little and controversial evidence is available from neuroimaging studies in progressive nonfluent aphasia (PNA). The goal of this study was to combine information from different imaging modalities in PNA compared with Alzheimer's disease (AD). Chemical shift imaging (CSI), voxel-based morphometry (VBM) and fluorodeoxyglucose positron emission tomography (FDG-PET) were used in 5 PNA, 10 AD patients and 10 normal subjects. Group comparisons revealed left anterior lateral temporal abnormalities (BA20/21) in PNA using CSI, VBM and PET in comparison to normal subjects. AD patients showed more limited hypometabolism within the same area. In addition left lateral parietal (BA40) abnormalities were demonstrated in our PNA as well as our AD group using PET and VBM (AD group only). Combining information from all imaging modalities on a single case basis revealed pathology within the left anterior lateral temporal and lateral parietal lobe both in PNA and AD. PNA and AD patients differed significantly, however, with respect to the frequency of medial temporal lobe and posterior cingulate/precuneus involvement. Although our results might not be generalizable to all subgroups of PNA, we conclude that medial temporal and posterior cingulate/precuneus cortex pathology as assessed by CSI and VBM or PET distinguish PNA from AD, whereas lateral temporal and parietal areas are involved in both conditions.

The objective of this study was to investigate phonological processing in the brain by using sub-syllabic speech units with rapidly changing frequency spectra. We used isolated stop consonants extracted from natural speech consonant-vowel (CV) syllables, which were digitized and presented through headphones in a functional magnetic resonance imaging (fMRI) paradigm. The stop consonants were contrasted with CV syllables. In order to control for general auditory activation, we used duration- and intensity-matched noise as a third stimulus category. The subjects were seventeen right-handed, healthy male volunteers. BOLD activation responses were acquired on a 1.5-T MR scanner. The auditory stimuli were presented through MR compatible headphones, using an fMRI paradigm with clustered volume acquisition and 12 s repetition time. The consonant vs. noise comparison resulted in unilateral left lateralized activation in the posterior part of the middle temporal gyrus and superior temporal sulcus (MTG/STS). The CV syllable vs. noise comparison resulted in bilateral activation in the same regions, with a leftward asymmetry. The reversed comparisons, i.e., noise vs. speech stimuli, resulted in right hemisphere activation in the supramarginal and superior temporal gyrus, as well as right prefrontal activation. Since the consonant stimuli are unlikely to have activated a semantic-lexical processing system, it seems reasonable to assume that the MTG/STS activation represents phonetic/phonological processing. This may involve the processing of both spectral and temporal features considered important for phonetic encoding.

We employed a source memory task in an event related fMRI study to dissociate MTL processes associated with either contextual retrieval or item recognition. To introduce context during study, stimuli (photographs of buildings and natural landscapes) were transformed into one of four single-color-scales: red, blue, yellow, or green. In the subsequent old/new recognition memory test, all stimuli were presented as gray scale photographs, and old-responses were followed by a four-alternative source judgment referring to the color in which the stimulus was presented during study. Our results suggest a clear-cut process dissociation within the human MTL. While an activity increase accompanies successful retrieval of contextual information, an activity decrease provides a familiarity signal that is sufficient for successful item recognition.

With this study, we explored the blood oxygen level-dependent responses within the temporal lobe to short auditory stimuli of different classes. To address this issue, we performed an attentive listening event-related fMRI study, where subjects were required to concentrate during the presentation of different types of stimuli. Because the order of stimuli was randomized and not predictable for the subject, the observed differences between the stimuli types were interpreted as an automatic effect and were not affected by attention. We used three types of stimuli: tones, sounds of animals and instruments, and words. We found in all cases bilateral activations of the primary and secondary auditory cortex. The strength and lateralization depended on the type of stimulus. The tone trials led to the weakest and smallest activations. The perception of sounds increased the activated network bilaterally into the superior temporal sulcus mainly on the right and the perception of words led to the highest activation within the left superior temporal sulcus as well as in left inferior frontal gyrus. Within the left temporal sulcus, we were able to distinguish between different subsystems, showing an extending activation from posterior to anterior for speech and speechlike information. Whereas posterior parts were involved in analyzing the complex auditory structure of sounds and speech, the middle and anterior parts responded strongest only in the perception of speech. In summary, a functional segregation of the temporal lobes into several subsystems responsible for auditory processing was visible. A lateralization for verbal stimuli to the left and sounds to the right was already detectable when short stimuli were used.