Chapter 2: Cognitive Neuroscience

• Neurons: cells specialized to receive and transmit information in the nervous system.
• Each neuron has a cell body, an axon, and dendrites.
• Cell body: contains mechanisms to keep cell alive.
• Axon: tube filled with fluid that transmits electrical signal to other neurons.
• Dendrites: multiple branches reaching from the cell body, which receives information from other neurons.
• Sensory receptors: specialized to respond to information received from the senses.
• Neuron receives signal from environment; information travels down the axon of that neuron to the dendrites of another neuron.

  Action potential
• Synapse: space between axon of one neuron and dendrite of another.
• Neurotransmitters: chemicals that affect the electrical signal of the receiving neuron.
• Increases chance neuron will fire.

  Excitatory
• Decreases chance neuron will fire.

  Inhibitory
• Not all signals received lead to action potential. True or False?

  True
• The cell membrane processes the number of impulses received.
• An action potential results only if the threshold level is reached.
• It is the interaction of excitation and inhabitation.

  Threshold
• Cerebral cortex contains mechanisms responsible for most of our cognitive functions.
• Lobe in reasoning and planning; language, thought, memory, motor functioning.

  Frontal
• Lobe in touch, temperature, pain, and pressure.

  Parietal
• lobe in auditory and perceptual processing; language, hearing, memory, and perceiving forms.

  Temporal
• Lobe in visual processing.

  Occipital
• Hippocampus: forming memories
• Amygdala: emotions and emotional memories.
• Thalamus: processing information from vision, hearing, and touch senses.
• Primary receiving areas for the senses: Occipital, Parietal, and Temporal
• Coordination of information received from all senses: Frontal
• It responds specifically to faces.

  Fusiform Face Area (FFA)
• Inability to recognize faces.

  Prosopagnosia
• It responds specifically to places.

  Parahippocampal Place Area (PPA)
• It responds specifically to pictures of bodies and parts of bodies.

  Extrastriate Body Area (EBA)
• Blood flow increases in areas of the brain activated by a cognitive task.

  Positron Emission Tomography (PET)
• Increases in activation indicated by red and yellow.
• Decreases in activation indicated by blue and green.
• Subtraction technique measure brain activity before and during stimulation presentation.
• Measures blood flow through magnetic properties of blood.

  Functional Magnetic Resonance Imaging (fMRI)
• Measure electrical activity on the scalp and make inferences about underlying brain activity.

  Event-Related Potential (ERP)
• Feature detectors: neurons that respond best to a specific stimulus
• Simple cells: neurons that respond best to bars of light of a particular orientation.
• Complex cells: neurons that respond best to an oriented bar of light with a specific length.
• Specificity coding: representation of specific stimulus by firing of specifically tuned neurons specialized to just respond to a specific stimulus.
• Distributed coding: representation by a pattern of firing across a number of neurons.