Kaisa Hartikainen

Pirkanmaa Hospital District, Tampere, Finland · Behavioral Neurology Research Unit

Burnout is becoming a global pandemic jeopardizing brain health, with a huge impact on quality of life, available workforce, and the economy. Knowledge of the impact of burnout on cognition, physiology, and physical activity (PA) in daily life allows for an improved understanding of the health consequences and everyday ramifications of burnout. Twe...

Hemispheric asymmetries in affective and cognitive functions have been extensively studied. While both cerebral hemispheres contribute to most affective and cognitive processes, neuroscientific literature and neuropsychological evidence support an overall right hemispheric dominance for emotion, attention and arousal. Emotional stimuli, especially...

Background: Alterations in executive functions, emotion regulation, and their interaction are common concomitants of depression. Executive dysfunction frequently lingers after treatment, has adverse effects on daily life, and predisposes to recurrence of depression. Yet, sensitive measures of executive function for reliable assessment of cognitive...

Objective findings of brain injury or dysfunction are typically lacking in mild traumatic brain injury (MTBI) despite prolonged post-concussion symptoms in some patients. Thus, there is a need for objective biomarkers of MTBI that reflect altered brain physiology underlying subjective symptoms. We have previously reported increased attention to thr...

Executive functions (EF) rely on intact fronto-subcortical networks. An insult, disorder or treatment compromising brain health may impair the functioning of these widespread networks and consequently disrupt EF. Changes in brain health due to treatment or disorder can be assessed by repeating an EF test at different time points, but practice effec...

Patients with lesion to the orbitofrontal cortex (OFC) experience challenges in emotional control and emotion-guided behaviors. The OFC is known to participate in executive functions and attentional control of emotion and our previous research suggests OFC lesion alters the balance between voluntary and involuntary attention and cognitive control w...

Neuromodulation techniques targeting limbic circuits can be used to treat refractory psychiatric or neurological disorders. However, objective measure for the impact of neuromodulation on affective brain circuits is lacking. Deep brain stimulation at a key node of the limbic circuit, the anterior thalamic nuclei (ANT-DBS), is used to treat refracto...

The mediodorsal nucleus of the thalamus (MD) with its extensive connections to the lateral pFC has been implicated in human working memory and executive functions. However, this understanding is based solely on indirect evidence from human lesion and imaging studies and animal studies. Direct, causal evidence from humans is missing. To obtain direc...

Vagus nerve stimulation is used for treating refractory epilepsy and major depression. This method has been shown to have a positive outcome in treatment on seizures in epilepsy, but its impact on human cognition remains unclear. The goal of this study was to study the immediate effects of vagus nerve stimulation on attention, cognition and emotion...

Vagus nerve stimulation (VNS) is used for treating refractory epilepsy and major depression. While the impact of this treatment on seizures has been established, its impact on human cognition remains equivocal. The goal of this study is to elucidate the immediate effects of vagus nerve stimulation on attention, cognition, and emotional reactivity i...

Injury to the orbitofrontal cortex (OFC) is a frequent consequence of head injury and may lead to dysfunctional regulation of emotional and social behavior. Dysfunctional emotional behavior may partly be related to the role of the OFC in emotion-attention interaction, as previously reported. In order to better understand its role in emotion-attenti...

OBJECTIVES Aortic valve replacement (AVR) surgery is associated with potential risk to cerebral injury. On the other hand, improved cardiovascular functioning after the surgery may have positive impact on brain health. The aim of this preliminary study was to investigate the impact of AVR surgery on cognition, specifically on higher cognitive contr...

Transcranial extraocular light affects the brains of birds and modulates their seasonal changes in physiology and behavior. However, whether the human brain is sensitive to extraocular light is unknown. To test whether extraocular light has any effect on human brain functioning, we measured brain electrophysiology of 18 young healthy subjects using...

List of p values for the analysis of ERP time windows. (DOCX)

Logistic regression analysis of error types did not reveal significant predictors. (DOCX)

Analysis of Event-related potential data. (DOCX)

Analysis of reaction times. (DOCX)

Patients treated with deep brain stimulation (DBS) provide an opportunity to study affective processes in humans with "lesion on demand" at key nodes in the limbic circuitries, such as at the anterior thalamic nuclei (ANT). ANT has been suggested to play a role in emotional control with its connection to the orbitofrontal cortex and the anterior ci...

Syväaivostimulaatiohoidon vaikutus tiedonkäsittely-ja tunnetoimintoihin • • Aivojen • syvien • osien • stimulaatiohoitoa • (deep • brain • stimulation, • DBS) • voidaan • käyttää • yhä • useamman • neurologisen • ja • psykiatrisen • sairauden • hoidossa. • • DBS-hoidolla • pyritään • moduloimaan • sairauden • kannalta • keskeisten • hermoverkostoje...

This study examined multiple biopsychosocial factors relating to post-concussion symptom (PCS) reporting in patients with mild traumatic brain injuries (MTBI), including structural (CT and MRI) and microstructural neuroimaging (diffusion tensor imaging; DTI). Patients with MTBIs completed several questionnaires and cognitive testing at approximatel...

Mild traumatic brain injury (MTBI) may be associated with compromised executive functioning and altered emotional reactivity. Despite frequent affective and cognitive symptoms in MTBI, objective evidence for brain dysfunction is often lacking. Previously we have reported compromised performance in symptomatic MTBI patients in an Executive-Reaction...

The aim of this study was to investigate whether emotion-attention interaction depends on attentional engagement. To investigate emotional modulation of attention network activation, we used a functional MRI paradigm consisting of a visuospatial attention task with either frequent (high-engagement) or infrequent (low-engagement) targets and intermi...

Background: Deep brain stimulation (DBS) of anterior thalamic nuclei (ANT) is a novel promising therapeutic method for treating refractory epilepsy. Despite reports of subjective memory impairments and mood disturbances in patients with ANT-DBS, little is known of its effects on cognitive and affective processes. Hypothesis: The anterior thalamu...

To examine factors relating to return to work (RTW) following mild traumatic brain injury (mTBI). One hundred and nine patients (Age: M = 37.4 years, SD = 13.2; 52.3% women) who sustained an mTBI. Inception cohort design with questionnaires and neuropsychological testing completed approximately 3 to 4 weeks postinjury. Emergency Department of Tampe...

ANT-DBS affect human emotional processing and cognitive functions

The purpose of this study was to examine the biopsychosocial outcome from uncomplicated mild traumatic brain injury (MTBI) within the first three weeks post injury. Participants were 48 prospectively enrolled patients from the Emergency Department of Tampere University Hospital, Finland who sustained an uncomplicated MTBI. At three weeks post injur...

The purpose of this study was to examine the reliability, validity and clinical usefulness of the Barrow Neurological Institute Fatigue Scale (BNI-FS) in patients with mild traumatic brain injuries (MTBI). Participants were 125 patients enrolled from the Emergency Department (ED) of Tampere University Hospital, Finland who had sustained an MTBI. Th...

A potential threat, such as a spider, captures attention and engages executive functions to adjust ongoing behavior and avoid danger. We and many others have reported slowed responses to neutral targets in the context of emotional distractors. This behavioral slowing has been explained in the framework of attentional competition for limited resourc...

Objective . To compare acute outcome following complicated versus uncomplicated mild traumatic brain injury (MTBI) using neurocognitive and self-report measures. Method . Participants were 47 patients who presented to the emergency department of Tampere University Hospital, Finland. All completed MRI scanning, self-report measures, and neurocogniti...

We examined the role of orbitofrontal (OF) cortex in regulating emotion-attention interaction and the balance between involuntary and voluntary attention allocation. We studied patients with OF lesion applying reaction time (RT) and event-related potential (ERP) measures in a lateralized visual discrimination task with novel task-irrelevant affecti...

Objectives: The purpose of this study was to examine the reliability, validity and clinical usefulness of the Barrow Neurological Institute Fatigue Scale (BNI-FS) in patients with mild traumatic brain injuries (MTBI). Methods and procedure: Participants were 125 patients enrolled from the Emergency Department (ED) of Tampere University Hospital, Fi...

In order to improve detection of subtle cognitive dysfunction and to shed light on the etiology of persistent symptoms after mild-to-moderate traumatic brain injury (TBI), we employed an experimental executive reaction time (RT) test, standardized neuropsychological tests, and diffusion tensor imaging (DTI). The Executive RT-Test, an Executive Comp...

Whether emotional distracters call for attentional resources has been discussed in several studies. We have earlier shown that brief unpleasant distracters captured right hemisphere (RH) attentional resources as evidenced with reduced event-related potential responses and increased reaction times to nonemotional left visual field/RH targets. The ai...

Rapid interaction of the emotional and attentional networks is critical for adaptive behavior. Here, we examined the effects of emotional stimulation on hemifield attention allocation using event-related potential and behavioral measures. Participants performed a visual-discrimination task on nonemotional targets presented randomly in the left or r...

During EEG suppression with isoflurane or sevoflurane anaesthesia, median nerve stimulation causes cortical responses of two kinds: an N20 wave with a latency of 20 ms and an EEG burst with a latency of 200 ms. We tested the possibility that median nerve stimulation during EEG suppression with propofol would cause an EEG response that was consisten...

The prefrontal cortex (PFCx) can be divided into the lateral, orbital and medial PFCx, which all contribute to attentional and novelty processing and flexible behaviors. The cytoarchitecture of lateral prefrontal cortex (LPFCx) is highly organized, differentiated, distinctly layered, granular isocortex while the orbitofrontal cortex (OFCx) is struc...

To assess the ability of the current diagnostic criteria for frontotemporal lobar degeneration (FTLD) to differentiate FTLD from AD. Thirty cases with autopsy-proven FTLD and 30 cases of AD, matched for Mini-Mental State Examination score, were identified from the clinical databases of three dementia subspecialty centers, and their charts were revi...

We examined the effects of bilateral orbitofrontal damage on emotional processing and hemispheric attention capacity. Participants (four bilateral orbitofrontal patients and age-matched controls) discriminated between upright and inverted triangles (target). Targets were randomly presented in the left (LVF) or right visual hemifield (RVF, 150 ms)....

We examined the effects of emotional stimuli on right and left hemisphere detection performance in a hemifield visual discrimination task. A group of 18 healthy subjects were asked to discriminate between upright and inverted triangles (target). Targets were randomly presented in the left or right visual hemifield (150 ms target duration). A brief...

The cortical responses to auditory stimuli were studied in 12 patients during isoflurane anaesthesia producing burst suppression (ETisof (SD) 1.4 (0.2) vol.%). Earphones were used to give 3-s trains of auditory click stimuli (60 clicks, 20 clicks per second, 80 dB, 0.1 ms) at irregular intervals. In 10 patients, the electroencephalography (EEG) sho...

During isoflurane-induced electroencephalographic (EEG) suppression, external stimuli evoke high-amplitude cortical responses (bursts). We tested whether bursts evoked by somatosensory stimuli would reliably distinguish intact somatosensory pathways from pathways in which peripheral nerve conduction had been blocked by local anesthetic. Ten subject...

In this paper we have studied cortical dynamics as assessed using graphical methods during deep anaesthesia. Graphical analysis was carried out by autocorrelation functions and return maps with different lags. During moderate and deep anaesthesia, the electroencephalogram (EEG) shows a burst suppression pattern, consisting of abruptly-occurring hig...

During isoflurane-induced electroencephalographic (EEG) suppression, external stimuli evoked high-amplitude cortical responses (bursts). We tested whether bursts evoked by somatosensory stimuli would reliably distinguish intact somatosensory pathways from pathways in which peripheral nerve conduction had been blocked by local anesthetic. Ten subjec...

We recorded visual evoked potentials (VEPs) to flash stimuli in moderately deep anaesthesia when EEG showed burst suppression pattern. Flash VEPs could consistently be recorded in all 8 test subjects during bursts but not during suppressions. We conclude that during isoflurane-induced EEG suppression VEPs to flash stimuli are also suppressed. This...

We studied cortical reactivity to auditory, visual, and somatosensory stimuli during moderate and deep levels of isoflurane anesthesia at which the electroencephalogram (EEG) showed burst suppression patterns, defined as alternating high amplitude bursts and periods of suppressed background activity. Fifteen patients scheduled for gynecologic surge...

We studied cortical reactivity to auditory, visual, and somatosensory stimuli during moderate and deep levels of isoflurane anesthesia at which the electroencephalogram (EEG) showed burst suppression patterns, defined as alternating high amplitude bursts and periods of suppressed background activity.Fifteen patients scheduled for gynecologic surger...

The aim of this study was to compare propofol produced EEG burst suppression with isoflurane produced burst suppression in rabbits and to see whether rabbits can serve as models in studying the effects of different anaesthetics on human EEG. We recorded EEG of eight rabbits anaesthetised with isoflurane and propofol. The isoflurane bursts had highe...

In this paper a developed novel algorithm for adaptive segmentation of Burst-suppression EEG is presented. The algorithm can detect bursts, suppression and artifacts dividing the signal into corresponding segments. A compact representation of burst-suppression EEG, useful in monitoring long-term recordings, is presented. In the second part of the p...

We studied EEG reactivity to visual stimuli during deep isoflurane (1.5–2.05 vol% end-tidal concentration) anaesthesia. Twelve patients were anaesthetized with isoflurane until burst suppression occurred in the EEG. Red LED goggles were used to give visual stimulation of 60 flashes, 4-ms duration each, at a frequency of 20 Hz. The stimuli, 3-s trai...

Barbiturate anaesthesia is used in the treatment of status epilepticus and severe epilepsy of children. EEG is then used as a measure of the depth of anaesthesia, burst suppression being an easily identified EEG pattern. In this case report we describe epileptiform discharges during EEG suppression in two children undergoing barbiturate anaesthesia...

The distribution and ultrastructure of lipopigments in the rat sympathetic, vagus and spinal ganglion neurons were studied in vivo and in vitro using fluorescence and electron microscopy. Newborn, 3-6 mo and 24-30 mo-old male Wistar rats were used. In vivo, the age pigments in the sympathetic neurons showed a tendency to form unipolar or bipolar ca...

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