Dealing with large number of brain images in group analysis involves two kinds of analysis. One is to extract the information and relations in the population of brains, and the other is to combine the information of individual brain in the group. Linear or nonlinear dimension reduction algorithms are the main tools to perform the first analysis, which is to show the information of the population. The hidden relations in the distribution are therefore able to be visualized in low-dimensional and visible space. Image registration is the critical part of the second analysis, which is to integrate the information or statistics of individual brains. The statistics are registered to a template which is commonly the mean brain image of the population so that the statistics from different subjects can be compared in the same stereotaxic space. The process of registering images to the template is called normalization. The quality of registration decides the normalization and the interpretability of results. This work constructed ordered representations, from a set of brain images, as the multiple templates. The ordered representations are derived from self-organizing map. A novel method, transformation diversion, based on the ordered representations is proposed to improve the registration, which is a non-linear deformation, in a general manner. The discriminative low-dimensional representation of the population of Alzheimer disease and normal subjects are also shown. The set of ordered representations not only shows the population information but also improve the normalization process.

A method is presented for the analysis of dynamic positron emission tomography (PET) data using sparse Bayesian learning. Parameters are estimated in a compartmental framework using an over-complete exponential basis set and sparse Bayesian learning. The technique is applicable to analyses requiring either a plasma or reference tissue input function and produces estimates of the system's macro-parameters and model order. In addition, the Bayesian approach returns the posterior distribution which allows for some characterisation of the error component. The method is applied to the estimation of parametric images of neuroreceptor radioligand studies.

A structural-feature-to-structural-feature configuration is naturally constructed using a set of sampled features from a cursive pattern. These features are sampled by maximally fitting bent ellipses in local strokes. This configuration is transformed into an undirected graph to resolve the asymmetric difficulty. The compatibility associated with the graph is further formulated into a devised Hopfield network, where both interfeature and interlink similarities are incorporated into the compatibility. We operate this network to recognize a radical as a whole in a handprinted pattern to accomplish the selective attention task.

In this work we present a self-organization matching approach to accomplish the recognition of handprinted characters drawn with thick strokes. This approach is used to flex the unknown handprinted character toward matching its object characters gradually. The extracted character features used in the self-organization matching are center loci, orientation, and major axes of ellipses which fit the inked area of the patterns. Simulations provide encouraging results using the proposed method.