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We describe new methods to analyse and control the self-assembly of gelation leading to exciting new soft materials. These materials have been shown to be of use to a wide range of applications including antimicrobial coatings, OPV devices, thermochromic materials and biomedical materials. Many of the described methods are novel or go beyond the state of the art. One of the analytical methods probes the surface chemistry of self-assembled hydrogel fibres to determine their pKa. This method not only determines the gel’s pKa but whether indeed a gel would form from a small molecule and what its rheological stiffness would be. This is the first incident of electrochemistry being used to determine the rheology of gels. Furthermore, a method to probe in the real time the self-assembly kinetics of a gelator to form a gel using multiple pulse amperometry is described. This method is expanded to complex multicomponent systems. Electrochemically fabricated hydrogels are developed and for the first time we show how the rheological properties can be controlled by controlling the electrochemical parameters. In addition to controlled rheological properties, the gels formed have unique mesh sizes and thermochromic properties. We introduce a new gelation trigger method for low molecular weight hydrogels. Dopamine autoxidation can be used to control the self-assembly of small molecules to form gels and we go on to describe how these gels can be used for antimicrobial purposes. To expand on the electrochemically fabricated hydrogels, we propose the oxidation of dopamine as a new electrochemical trigger. We describe how the rheological properties of the gels can be controlled and how they are potentially suitable for biomedical applications. Finally, we describe a method to control the self-assembly of both single and multi-component gel networks by temperature and use an array of analytical techniques to show this. We expand on this work to show how the temperature control can form gels with varying networks which lead directly to changes in the efficiency of electron transfer.

As humans, we share a strong desire to interact with other people. This strong motivation to engage socially directs our attention to social signals, guides us to participate in behaviours that help us to establish, maintain, and enhance our relationships with others, and allows us to enjoy social interactions and to find them rewarding. However, the Social Motivation Theory posits that individuals with Autism Spectrum Disorder may have deficits in social motivation, which may lead to difficulties in social interactions and communication. This thesis employs several methods (including behavioural, psychophysiological and neurological) to investigate social motivation in the typical population, and examines how autistic traits influence the reward value assigned to social stimuli. Specifically, this thesis investigates social motivation in relation to an important type of social stimulus, namely biological motion, which has not been the topic of research investigating social motivation. The first empirical chapter (Chapter 3) presents a behavioural experiment that investigates the reward value of biological motion, and how this value changes as a function of autistic traits among the participant sample. The following chapter (Chapter 4) comprises two eye-tracking experiments aiming to address how viewing biological motion affects attention and arousal. The final empirical chapter (Chapter 5) employs functional magnetic resonance imaging (fMRI) to examine brain regions involved in the anticipation of social reward or social punishment in a task where participants work to either receive positive feedback or avoid negative feedback. As a whole, this thesis sheds valuable new light on questions surrounding social motivation, such as whether individuals find a broad conceptualisation of social stimuli rewarding and whether the perceived reward value of social stimuli is influenced by autistic traits. The findings from this work have important implications for developing a greater understanding of social motivation and human social behaviour more broadly.