Lecture 11

Question 1

Describe the research study with M.P.

Answer 1

patient M.P., who had damage to his
temporal lobe which impaired his ability to name objects

• Cued in one of two ways before seeing a series of pictures in which they must
  respond once they’ve found the target (indicated by the cue)

1. Name: The name of the target object (‘cup’)
2. Function: A description of the function of the target object (‘any item you
   can drink from’)

• Cueing an object with it’s function produced better performance

Question 1

What are affordances?

Answer 1

They made up of information that indicates what an object is used for, indicating a ‘potential for action’, or “…what the environment offers the animal, what it provides or furnishes.”

Question 2

What is an action affordance?

Answer 2

action-
based information (the
affordance, or what it does,
and the action associated
with it) is automatically
activated during early stages
of processing

Question 3

Describe the visual direction strategy of navigation

Answer 3

A visual direction strategy involves
keeping ones body pointed toward a
target

• Walkers simply correct their trajectory
  when target drifts to left or right in their
  visual field

Question 4

Describe spatial updating

Answer 4

the processes involved with
keeping track of one’s position
as they move around within an
environment

Question 5

What is wayfinding?

Answer 5

navigating to a destination that requires making a series
of turns

Question 6

What are landmarks?

Answer 6

objects on the route that serve as cues to indicate where to turn

Question 7

What happened during the training phase of the Hamid study?

Answer 7

Participants learned how to navigate a virtual maze (with pictures of common
objects serving as landmarks)

Question 8

What happened during the testing phase of the Hamid study?

Answer 8

Particpants attempt to reach specific destinations within same virtual maze
environment

Question 9

What critical comparison was drawn between these two trials?

Answer 9

fixation number on decision-
point landmarks as compared to non-decision-
point landmarks

Question 10

Describe the museum study

Answer 10

• Participants were then presented with objects from three categories (while
  being scanned) and indicating whether or not they remember each:
  1. Decision-point landmarks
  2. Non-decision point landmarks
  3. Objects they were not shown during the experiment
• For objects that were remembered,
  those at decision-points were associated
  with greater parahippocampal gyrus
  activation than those at non-decision
  points

Question 11

What is topographical agnosia?

Answer 11

an inability to recognize landmarks

• Associated with damage to the parahippocampal gyrus
• Navigation deficits are a common symptom

F.G. navigated his hometown by relying
heavily on street signs (people are
adaptable and can often learn to use
whatever information is available when
conventional sources are lacking!)

Question 12

What are place cells?

Answer 12

neurons that fire when in
particular locations (their ‘place field’)

Question 13

What are grid cells?

Answer 13

similar in concept to place cells but have
multiple place fields that are systematically distributed
(and therefore follow a sort of spatial regularity)

Question 14

What are head direction cells?

Answer 14

fire depending on direction animal if facing (recall
Gibson’s complaint about pilots not being able to turn their heads in lab-
based experiments!)

Question 15

What are border cells?

Answer 15

fire when an animal is near the edge of an environment

Question 16

Describe the monkey mirror neuron study

Answer 16

• Mirror neurons in the cortex of monkeys respond when a monkey grasps an object, as well as when an experimenter grasps an object
• Response to the observed action ‘mirrors’ the response of what happens when the monkey grasps something themselves
• Diminished/little response if object grasped less directly, e.g. by pliers

Question 17

What are audiovisual mirror neurons?

Answer 17

They respond to stimuli associated with both seeing
and hearing action

• May help link sensory perceptions and motor actions

Question 18

Describe reaching and grasping

Answer 18

Reaching and grasping are two of
the most common actions taken in
the environment and have great
adaptive value

• As with many topics related to
  perception, entails more complexity
  than we typically attribute
• In part, this has to do with the
  automaticity with which we can
  engage in these behaviours

Question 19

Differentiate between the role of dorsal and ventral streams in reaching

Answer 19

• Identifying the object (ventral)
• Positioning hand and fingers to
  grasp (dorsal)

Question 20

What is the parietal reach region?

Answer 20

Contains neurons that become active while reaching/grasping

Question 21

Describe the monkey light grasping study

Answer 21

Monkey is briefly shown object with lights on, then lights turn off and a cue prompts the monkey to reach for object (Fattori et al., 2010)

• Requires monkey to not only remember location of object but also it’s form (to accommodate a hand grip)
• Specific neurons found that respond to trials requiring specific grips (image at right)
• Visuomotor grip cells become active when simply looking at objects

Question 22

What is proprioception?

Answer 22

the ability to
sense body position and movement

Question 23

Where are proprioception receptors located?

Answer 23

the elbow joint,
muscle spindle, and tendon help guide reaching/
grasping behaviour

Question 24

Describe the size-weight illusion

Answer 24

Erroneously predicting weight
when observing two differently sized objects that have the same weight. The error occurs when the perceiver predicts that larger object will be heavier, and therefore uses more force to lift it, causing it to be lifted higher and to feel lighter