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Introduction: Verbal memory is a complex and fundamental aspect of human cognition. However, traditional sum-score analyses of verbal learning tests oversimplify underlying verbal memory processes. We propose using process models to subdivide memory into multiple processes, which helps in localizing the most affected processes in impaired verbal memory. Additionally, the model can be used to address score and process variability. This study aims to investigate the effects of cancer and its treatment on verbal memory, as well as provide a demonstration of how process models can be used to investigate the uncertainty in neuropsychological test scores., Method: We present an investigation of memory process scores in non-CNS cancer survivors ( n  = 184) and no-cancer controls ( n  = 204). The participants completed the Amsterdam Cognition Scan (ACS), in which classical neuropsychological tests are digitally recreated for online at-home administration. We analyzed data from the ACS equivalent of a Verbal Learning Test using both traditional sum scores and a Bayesian process model., Results: Analysis of the sum score indicated that patients scored lower than controls on immediate recall but found no difference for delayed recall. The process model analysis indicated a small difference between patients and controls in immediate retrieval from both the partially learned and learned states, with no differences in learning or delayed retrieval processes. Individual-level analysis shows considerable uncertainty for sum scores. Sum scores were more certain than single trials. Retrieval parameters also showed less uncertainty than learning parameters., Conclusion: The Bayesian process model increased the informativity of Verbal Learning test data, by showing uncertainty of the traditional sum score measurements as well as how the underlying processes differed between populations. Additionally, the model grants insight into underlying memory processes for individuals and how these processes vary within and between them.

The defective parts of the visual field of two brain-injured patients were stimulated with different spots of light. There is evidence for at least five independent visual functions which can be restored due to constant stimulation of the blind part of the visual field: (1) The constant stimulation of the blind part of the visual field with spots of white light leads to an increase of the visual field for the perception of white light only. (2) The constant stimulation with spots of light of different wavelengths leads to an increase of the visual field for different color perception. To enlarge the visual field for the perception of the color red, a light stimulus with the wavelength of 656 nanometers (nm) was used; for the visual field for the perception of the color green 525 nm; for yellow 578 nm; and for blue 450 nm. (3) The constant stimulation of the blind visual field with black and white light bars of different orientations and constellations leads to an increase of the foveal acuity and an improvement of form perception in the periphery of the visual field. The results suggest that the recovery of visual functions, different color perception and form perception, may depend upon neuronal regeneration in the human visual cortex; regeneration occurs with adequate and constant stimulation of its specific neurons.