In this talk I will cover QEEG research in acute stroke, also ageing and cognitive decline, including studies done by myself and also international studies. The appearance of slow delta activity (1-4 Hz) is typical in acute stroke, and alpha activity is also affected (e.g. slowed) in more severe strokes. Our studies have shown that QEEG measures of delta power, and delta/alpha power ratio, are very informative for assessing response to acute treatments and also in relation to predicting functional outcomes from stroke. Our current hypothesis is that delta activity may reflect a functional disconnection between cortical and thalamic regions (thalamo-cortical dysrhythmia).
We have also found that early measures of alpha slowing in acute stroke patients may help predict cognitive outcomes. In other studies we have shown that high, resting-state theta (4-7 Hz) power in healthy older adults is associated with better cognitive function. This theta activity is generated in brain networks incorporating medial temporal, anterior cingulate and other cortical regions. We have also found theta power to be lower in people with mild cognitive impairment. Considering various findings from our studies and those of others, we have proposed that two forms of theta-frequency activity exist; one indicative of healthy neurocognitive function and the other, of alpha slowing linked to (future) cognitive decline.
I will aim to discuss the potential implications of QEEG findings such as these, with regard to neurofeedback protocols aiming to address and ameliorate particular conditions or symptoms.