No description available.

No description available.

No description available.

No description available.

No description available.

This thesis explores the mediating effects of personality on attention and performance during the learning of novel categories. Major theories of category learning emphasise the role of dopamine on a variety of processes engaged during such learning. Two core personality domains, namely extraversion and a cluster of traits collectively termed impulsive, anti-social, sensation seeking (ImpASS) were considered These personality traits were of interest because it has been suggested that their biological basis may partly reflect variation in dopaminergic neurotransmission. Schizotypal personality, owing to its association with schizophrenia, may also reflect dopaminergic function and was also considered.

In a series of three studies the relationship between imitative learning emulation learning and tool use was explored through the replication and extension of an apparatus and an experimental paradigm developed by Nagell Olguin & Tomasello (1993). In addition to examining whether young children were capable of imitative learning studies one, two, and three explored the presence of affordance learning through the more sensitive measure of learning about relative efficiency. Study one found evidence of imitative learning but no evidence of affordance learning in children of 18- to 48-months of age. It was hypothosised that a number of procedural effects may have been inhibiting affordance learning" one of which was explored by using a second, novel problem-solving task in study two with no evidence of affordance learning emerging. Study three explored another procedural effect and found tentative evidence of affordance learning in 3-year-old children. Although the findings of studies one, two and three provided broad support for the position that children tend to use imitation over emulation they suggest that different learning mechanisms may be intertwined.

From the moment of birth, there is a direct interaction to our environment. This is the main principle of learning (Sutton & Barto, 1998). For instance when a new-born is playing there is a sensory and motor connectivity to the environment by allowing the cause and effect information, the outcome of an action and the achievement of a goal to be learned (Sutton & Barto, 1998). Moreover, learning provides lmowledge about us and our environment. Wliether we learn to ride a bicycle in adolescence or learn to drive a car in adulthood we are conscious of the several responds to our actions, which we want to influence what is happening in our behaviour during the lifespan. Learning from interactions is considered as an important field of research, underlying all theories of behaviour. The approached theory we explored is called reinforcement learning and it is more goal directed learning from interaction. Previous work in this area has focused mainly to what extend people learn to make choices that lead to positive outcomes and avoid making those that lead to negative outcomes (Frank et aI., 2004). This thesis extended this work by behaviourally investigating reinforcement learning across life span (7-55 years old). Using the reward bias coefficient (RBc) a measurement of an individual's tendency to follow reward or avoid punishment, in the face ofunceliainty, results demonstrated significant age differences in learning from positive and negative probablistic feedback between these age groups (7-10, 11-14, 15-18, 19-35 and 40-55 years old). This is the first study to compare qualitative changes in RBc across lifespan indicating the importance of positive and negative feedback learning in cognitive perfomance.

No description available.

No description available.