Current Research Projects Department Cognitive Neuropsychology
By neurofeedback training individuals may learn to modulate their EEG and how to change it voluntary. We have developed a novel neurofeedback training device so that instrumental conditioning of alpha activity (8-12 Hz or IAF +/- 2 Hz) could be applied in a consumer product aimed at normal, healthy, everyday users. After investigating the feasibility of this device and training protocol (1), we have looked into the time-course of the training effects in the EEG (2), and the training effects at a behavioural level in different target groups, such as soldiers and gymnastic athletes. We hypothesized that our training could increase cognitive performance and well-being (such as feeling more calm), because participants are getting better at focusing their attention.
- Van Boxtel, G.J.M., Denissen, A., Jager, M., Vernon, D., Dekker, M.K.J., Mihaljovic, V. & Sitskoorn, M.M. (2012). A novel self-guided approach to alpha activity training. International journal of psychophysiology, 83(3), 282-294
- Dekker, M.K.J., Sitskoorn, M.M., Denissen, A.J.M., & Van Boxtel, G.J.M. (2014). The time-course of alpha neurofeedback training effects in healthy participants. Biological Psychology, 95, 70-73.
Subjective cognitive complaints
Do subjective complaints correlate with objective impairments. A number of studies investigating subjective cognitive complaints in the healthy elderly and in neurological populations suggest that there is no one-to-one mapping.
Some studies on this topic:
- Are subjective cognitive complaints relevant in preclinical Alzheimer's disease? A review and guidelines for healthcare professionals (RE Mark, MM Sitskoorn Reviews in Clinical Gerontology 2013, 23 (01), 61-74)
- Subjective cognitive complaints after stroke: a systematic review (MWA van Rijsbergen, RE Mark, PLM de Kort, MM Sitskoorn Journal of Stroke and Cerebrovascular Diseases 2013/6/22)
- The COMPlaints After Stroke (COMPAS) study: protocol for a Dutch cohort study on poststroke subjective cognitive complaints (MWA van Rijsbergen, RE Mark, PLM de Kort, MM Sitskoorn BMJ open 3 (9), e003599)
Beside the topic of 'subjective cognitive complaints', Ruth Mark also investigates behaviour and cognition in people with Alzheimer's dementia and carries out both practical and scientific studies on memory, music perception and emotions.
Cognitive rehabilitation in patients with brain tumors
A multicenter, randomized controlled trial
Gehring K, Taphoorn MJB, Aaronson NK, Sitskoorn MM
Many patients with brain tumors suffer from cognitive deficits. In 2008, we completed the first randomized controlled trial worldwide of a cognitive rehabilitation program in 140 lower-grade glioma patients. It incorporated both individual strategy training and retraining of attention. The program had salutary effects on short-term cognitive complaints, and on longer-term neuropsychological test performance and mental fatigue.
The study received national and international rewards, and led to more research on interventions for cognitive deficits in patients with brain tumors (see below).
- Gehring K, Sitskoorn MM, Gundy CM, Sikkes SAM, Klein M, Postma TJ, van den Bent MJ, Beute GN, Enting R, Kappelle AC, Boogerd W, Veninga T, Twijnstra A, Boerman DH, Taphoorn MJB, Aaronson NK. Cognitive rehabilitation in patients with gliomas: a randomized, controlled trial. Journal of Clinical Oncology, 2009; 27: 3712-3722.
- Gehring K, Aaronson N, Taphoorn M, Sitskoorn MM. A description of a cognitive rehabilitation programme evaluated in brain tumour patients with mild to moderate cognitive deficits. Clinical Rehabilitation, 2011; 5: 675-692.
- Gehring K, Aaronson NK, Gundy CM, Taphoorn MJ, Sitskoorn MM. Predictors of neuropsychological improvement following cognitive rehabilitation in patients with gliomas. Journal of the International Neuropsychological Society, 2011; 17: 256-266.
- Gehring K, Sitskoorn MM, Aaronson NK, Taphoorn MJB. Interventions for cognitive deficits in adults with brain tumours. The Lancet Neurology, 2008; 7: 548-560.
A tablet app (ReMind) based on an evidence-based cognitive rehabilitation program
for patients with gliomas
Gehring K, Hoogendoorn P, Sitskoorn MM
In a joint patient/researcher initiative, all elements of the previously evaluated cognitive rehabilitation program (see above) are converted into a tablet app to increase its accessibility to glioma patients.
The app ReMind is developed in cooperation with patients and patient advocates, neuro-oncology specialists, film director, actors, scriptwriter, translator, and software engineers. We make use of the additional possibilities this new environment offers, while maintaining the content largely identical to the previously evaluated version. The app is developed in both Dutch and English.
ReMind consists of instructional texts that are provided in videos presented by a ‘trainer’, in audio format and read-only, to teach compensation techniques. Adaptive exercises to practice application of strategies are provided throughout the program, with the possibility of guidance from a significant other. Game-like exercises are presented to train four modes of attention.
This iOS app will be launched for use in Dutch- and English speaking countries. The refinement of the app will be ongoing, and the development of an Android version will be one of the future projects.
In the meantime, this novel mode of administration of the cognitive rehabilitation program will be evaluated in several studies throughout the Netherlands, including a randomized trial on supervised and unsupervised delivery of ReMind training and assessment of effects with neuroimaging. The effectiveness of the program will also be evaluated in an international study.
A multi-center pilot RCT
on the efficacy of home-based exercise to improve cognitive functioning in glioma patients
Gehring K, Stuiver MM; Rutten GJ, Taphoorn MJB, Aaronson NK, Sitskoorn MM
Recent findings demonstrate that physical exercise is effective in delaying or ameliorating cognitive decline, in particular in older adults and select neurological patient populations. Studies of exercise interventions in patients with cancer already demonstrated to have beneficial effects on physical fitness, fatigue, psychological well-being, and quality of life.
This pilot RCT investigates the efficacy of a home-based exercise program in improving cognitive functioning in 60 lower-grade glioma patients.
Clinically stable patients with lower-grade glioma undergo baseline neuropsychological testing, and are subsequently referred for cardiorespiratory exercise testing to determine room for improvement of physical fitness and to tailor an individual exercise program based on VO2max. Forty eligible patients will are randomized to the intervention group and undergo the 6-month home-based intervention. Patients exercise 3 times per week for 6 months, during 20 to 45 minutes at an increasing intensity of 55 to 85% of their maximum heart rate. Patients wear heart rate monitors and are supervised by a physical therapist via internet and telephone. Twenty patients in the active control group are advised to walk regularly.
Neuropsychological test performance, physical fitness, self-reported cognitive symptoms, fatigue, sleep, mood and quality of life will be assessed at baseline and after 6 months.
To our knowledge, this is the first study that evaluates the effects of an exercise intervention in patients with gliomas, and one of the first studies that employs exercise as intervention to improve cognitive functioning in patients with cancer.
Predicition and recovery of cognitive impairment in neurosurgical patients
Meskal I, Gehring K, Rutten GJM, Sitskoorn MM
A substantial (but unknown) number of patients, who are admitted for an intracranial neurosurgical procedure (e.g., resection of a brain tumor or microvascular decompression), already have cognitive deficits prior to surgical treatment. Additional cognitive deficits may occur after surgery and even persist for a prolonged period. Because cognitive functions are essential for our daily social, occupational and personal life, is it important to have a full understanding of factors that can predict cognitive functioning in patients before and after surgery.
The aim of the study is twofold: 1) to develop a prediction model from which clinicians can better inform patients in advance of possible cognitive sequelae following surgical treatment and the chances of recovery over time, 2) to attend neurosurgeons and researchers to the importance of cognitive impairments and their consequences in order to further improve care and quality of life in patients receiving surgical treatment.
The study is set up as a prospective follow-up design to patients receiving intracranial neurosurgical treatment. Patients complete preoperative neuropsychological tests, with a brief (30 minutes) computerized screening battery (i.e., CNS Vital Signs, and questionnaires and are followed up prospectively at 3 and 12 months after surgery. Patients are compared with healthy controls, recruited from the general population matched for age, gender, and educational level. Healthy controls are tested at the same time points. Prospectively collected data on demographic, medical/clinical history and psychological variables (i.e., depression, anxiety, subjective cognitive complaints and pain) are used to identify predictors of objective cognitive deficits at 3 and 12 months after surgery.
Effects of pulmonary rehabilitation on cognitive functioning, anxiety, mood, and quality of life
Campman CAM, van Ranst D, Meijer JW, Sitskoorn MM
Chronic Obstructive Pulmonary Disease (COPD) primarily affects pulmonary functions. COPD is a chronic disease and a substantial number of COPD patients will experience anxiety, depression, decreased quality of life, and impaired physical functioning. In addition, but rather unknown, COPD is associated with cognitive impairment. Pulmonary rehabilitation (PR) is shown to be effective in improving quality of life, physical functioning, anxiety, and depression for patients with COPD. It is also expected that PR can improve cognitive functioning in patients with COPD, because physical improvement led to cognitive improvement in healthy people and other patient populations. However, the effects of PR on cognitive functioning are not clear yet.
The aim of this project is to study the effects of PR on cognitive functioning, anxiety, mood, and quality of life in patients with COPD. As most studies focus on the group level, we intend to also look at the individual patient level. That is, in addition to investigating the effects of pulmonary rehabilitation on the group level, we explore which characteristics predict recovery in the individual patient.
This study was designed as a andomized controlled trial. Patients with moderate to very severe COPD were randomly assigned to the intervention group or the waiting-list control group. Patients in the intervention group were tested on subjective and objective cognitive functioning, anxiety, mood, and quality of life before and after PR. Patients in the waiting-list control group were tested on the same measures before and after waiting time and then started PR. The PR in our study is an extensive, full-time program of twelve weeks aimed at improving quality of life and physical functioning.
- Campman, C.A.M., & Sitskoorn, M.M. (2013). Better care for patients with COPD and cognitive impairment. The Lancet Respiratory Medicine, 1(7), 504-506.
When is now?
Humans are pretty good judging the temporal order (which comes first?) of 2 clicks or 2 flashes. However, we have great difficulty judging audiovisual temporal order of a click and flash. Why? Frankly, we don't know. However, we demonstrated that perception of audiovisual synchrony is adaptable. This is good news if you have to watch a poorly dubbed movie: In the end, you get used to it.
- Vroomen, J., Keetels, M., de Gelder, B., & Bertelson, P. (2004). Recalibration of temporal order perception by exposure to audio-visual asynchrony. Cognitive Brain Research, 22, 32-35.
Why can't you tickle yourself? Probably because your brain predicts what it will hear, see, and feel in the next second, and then dampens this sensory information. This explains why it is so surprising to hear youself on tape. With EEG we demonstrated that predictions about 'when' and 'what' occur at different time scales in the brain. Also, patients with schizophrenia have much less sensory dampening.
- Stekelenburg, J. J., & Vroomen, J. (2007). Neural correlates of multisensory integration of ecologically valid audiovisual events. Journal of Cognitive Neuroscience, 19, 1964-1973.
- Stekelenburg, J. J., Maes, J. P., van Gool, A. R., Sitskoorn, M., & Vroomen, J. (2013). Deficient multisensory integration in schizophrenia: An event-related potential study. Schizophrenia Research, 147, 253-261. doi:10.1016/j.schres.2013.04.038
Elementary speech sounds like /b/ or /d/ (phonemes) are sometimes ambiguous because each speaker has its own funny accent. We demonstrated that lipread information 'recalibrates' the auditory system so that the once ambiguous phoneme is not that ambiguous anymore. Seeing a speaker thus really helps, even if the video is later turned off. We also have ideas where all this might occur in the brain.
- Bertelson, P., Vroomen, J., & de Gelder, B. (2003). Visual recalibration of auditory speech identification: A McGurk aftereffect. Psychological Science, 14, 592-597.
- Kilian-Hütten, N., Vroomen, J., & Formisano, E. (2011). Brain activation during audiovisual exposure anticipates future perception of ambiguous speech. NeuroImage, 57, 1601-1607. doi:10.1016/j.neuroimage.2011.05.043
Where did I hear that?
Humans can localize sounds in space. This needs to be flexible because ears get clogged and each room has it's own acoustics. We demonstrated that the apparent location of a sound shifts towards a flash that is synchronized with the sound. That's the illusion the ventriloquist makes his living of. We currently examine whether eye-gazes shift sound location like flashes do.
- Vroomen, J. & Stekelenburg, J. J. (2014). A bias-free two-alternative forced choice procedure to examine intersensory illusions applied to the ventriloquist effect by flashes and averted eye-gazes. European Journal of Neuroscience.
Bertelson, P., Frissen, I., Vroomen, J., & de Gelder, B. (2006). The aftereffects of ventriloquism: Patterns of spatial generalization. Perception & Psychophysics,68, 428-436.