NEUR1020 W10

• What is the difference between top-down and bottom-up processes?


  Top-down = conscious cognitive control/choice, modulated by prior knowledge and experience.

  Bottom-up = external stimuli or unconscious state.
• Which lobe has the crucial role of attention?

  Parietal lobe
• What is attention?


  Directing eye-movements to explore the visual world
• What happens when damage to the parietal lobe occurs?

  Causes a syndrome called spatial neglect
• What is spatial awareness?

  Represents spatial location of objects around us for guiding actions. It links vision to action
• What is William James' definition of attention?

  Taking possession of the mind, in clear and vivid form, of one out of what seems several simultaneously possible objects or train of thought
• What is the characteristic of selectivity in attention?


  Where we select and prioritise stimuli based on location (moving spotlight) and relevant features
• Is capacity of attention limited or infinite?


  Limited, so we use attention to filter and prioritise sensory information
• What are some processes controlled by the top-down conscious processes?


  Selecting and prioritising according to a task, voluntarily shifting visual attention to search, and choosing features for selection ("focus of attention")
• What are some processes controlled by the bottom-up unconscious processes?


  Attention captured involuntarily by highly salient (standing out) stimuli and things that pop-out
• Lesion to the parietal cortex results in?

  Spatial neglect, which is mostly caused by stroke (blockage of blood supply)
• What happens when you have spatial neglect?

  Ignores or is unaware of perceiving stimuli on the side contralateral to the brain lesion. It is NOT due to any sensory deficit, implying that vision is still normal
• What is another symptom of spatial neglect?

  Simultagnosia = cannot perceive multiple objects simultaneously, hence will ignore objects on the neglected side of vision
• What is the importance of the parietal cortex?

  Necessary for attention to objects and space on the contralateral side
• What is the central sulcus?

  The dividing line between the frontal and parietal lobes
• What are the functions of the frontal lobe?

  Cognitive control of behaviour and executive functions (reasoning, planning, problem-solving, inhibitory control and working memory)
• What is the inhibitory control under executive functions crucial for?

  Control of behaviour, such as the selection of appropriate actions and suppressing inappropriate actions
• What are the disorders associated with impaired inhibitory control?


  Attention Deficit Hyperactivity Disorder (ADHD): impulsive behaviours and difficulty preventing distractions.

  Obsessive Compulsive Disorder (OCD): repetitive compulsive behaviour (washing, cleaning, checking).

  Reward Addictions: compulsive behaviours such as gambling, internet shopping.
• What did Egas Moniz introduce to relieve psychiatric disorders before medications were invented?


  Prefrontal leucotomy (lobotomy), which is the surgical cutting of the nerve fibres in that brain region. He did this based from observations of chimpanzees having the "calming" effect
• What is the Fronto-temporal Dementia (FTD)?


  Degeneration (loss of neurons) in the frontal and temporal lobes, and is the 2nd most common dementia after Alzheimer's.
• What are symptoms for FTD?


  Disinhibition --> increasingly inappropriate actions

  Apathy --> lack of motivation and emotionally distant

  Loss of empathy --> unaware of other's emotions

  Deficits in executive functions (Neuropsychological Testing) --> planning, reasoning, organisation of complex tasks