Participate in Cognitive Neuroscience Experiments for extra credit!

Mental Representations Here’s one possible way to represent information in a brain… A “labeled line”: A “labeled line” -Activity on this unit “means” that a line is present -This one encodes bars or lines

Mental Representations Mental representations can start with sensory input and progress to more abstract forms – texture defined boundaries are representations arrived at by synthesizing the local texture features

Mental Representations Mental Representations can interfere – Stroop task: name the colour in which the word is printed (I.e. don’t read the word, just say the colour

Mental Representations Mental Representations can interfere – Stroop task: name the colour in which the word is printed (I.e. don’t read the word, just say the colour RED

Mental Representations Mental Representations can interfere – Stroop task: name the colour in which the word is printed (I.e. don’t read the word, just say the colour BLUE

Mental Representations Mental Representations can interfere – Stroop task: name the colour in which the word is printed (I.e. don’t read the word, just say the colour GREEN

Mental Representations Mental Representations can interfere – Stroop task: name the colour in which the word is printed (I.e. don’t read the word, just say the colour RED

Mental Representations Mental Representations can interfere – Stroop task: name the colour in which the word is printed (I.e. don’t read the word, just say the colour BLUE

Mental Representations Mental Representations can interfere – Stroop task: name the colour in which the word is printed (I.e. don’t read the word, just say the colour GREEN

Mental Representations Mental Representations can interfere – Stroop task: name the colour in which the word is printed (I.e. don’t read the word, just say the colour – The mental representation of the colour and the representation of the text are incongruent and interfere – one representation must be selected and the other suppressed – This is one conceptualization of attention

Mental Representations Representations in neural a neural code aren’t limited to sensory information Place cells in hippocampus represent location of an animal in a local coordinate system – Spike rate on a place cell is high when the animal is near one spot but trails off when the animal moves away Moser et al. 2008

Mental Representations Representations in neural a neural code aren’t limited to sensory information Motor Neurons represent intended direction of limb movement – Spike rate increases when monkey is going to make a movement in a particular direction and trails off if the monkey is going to make a very different movement

Mental Representations The cognitive neuroscientists asks: – where are these representations formed? – What is the neural mechanism? What is the code for a representation? – What is the neural process by which representations are transformed?