What is Where and How to Get There The Neurocognition of Space Albert Postma

2. What is Where and How to Get There The Neurocognition of Space Albert Postma Psychological Laboratory, Utrecht a.postma@fss.uu.nl http://www.fss.uu.nl/psn/pionier/

3. Examples of tasks involving mental spatial processes - Does the trunk of elephant reach to the ground if the animal is standing in a normal (horizontal) position? D D J - Imagine the capital letter ‘d’. Turn it 90° to the left. Place the letter ‘j’ below it in the centre. What do you see? - Attend the entrance door of the classroom - Lay down your pencil…

4. (Spatial Cognition:= the collection of mental abilities which involve the processing of spatial features of our environment or of complex objects (ranging from perception, attention, motor action to memory). Spatial features include distance (depth), relative and absolute position, orientation (direction)

5. Why Study Spatial Cognition? - Essential for many daily activities (ecological importance) - Several recent interesting neurocognitive findings - Space is the common attribute of all our senses - Other cognitive acts may essentially be ‘spatially motivated’ (e.g. language evolution) - High extent of specialization of neural circuits for spatial tasks

6. How does our brain represent space?

8. How is spatial information further processed after the primary visual cortex?

9. Dorsal and ventral stream

10. Dorsal and ventral stream • The anatomical separation of visual cortical processing within a dorsal and ventral stream is well established. • What about the functions that are subserved by these two visual streams? • Ungeleider & Mishkin (1982) • Based their distinction on stimulus attributes • Ventral stream: What is the stimulus • Dorsal stream: Where is the stimulus

11. Dorsal and ventral stream Ungeleider & Mishkin (1982) Experimental evidence that supports this functional distinction: Lesion studies with monkeys Two tasks: Object discrimination and spatial discrimination.

12. Dorsal and ventral stream • Ungeleider & Mishkin (1982) • Lesion studies with monkeys • Object discrimination • Delayed non-matching to sample • Monkeys with a bilateral lesion of the inferotemporal lobe are impaired on this task.

13. Dorsal and ventral stream • Ungeleider & Mishkin (1982) • Lesion studies with monkeys • Spatial discrimination • Landmark discrimination • Choose the foodwell closer to the ‘landmark’. • Monkeys with bilateral posterior parietal lesions are impaired on this task.

14. Dorsal and ventral stream The conclusion that the landmark task showed that monkeys with parietal lesions were impaired in spatial discrimination was criticized by Milner & Goodale (1995) for several reasons. Instead they proposed a different division of labour based on what the visual information is used for, rather than the stimulus characteristics. Ventral: Visual perception Dorsal: Visual guidance of goal-directed action

15. Dorsal and ventral stream • Patient studies: • Optic ataxia: • Disorder of spatial perception or visually guided action? • Jakobson et al. (1991), Jeannerod et al. (1994) report a patient who was impaired in adjusting their grip aperture to the size of the object.

16. Dorsal and ventral stream • Patient studies: • Patient DF: • Visual form agnosia • Impaired recognition of • form • orientation, location • However, she can use visual information to guide her actions

17. D.F. Controles

18. D.F. Controles

19. Dorsal and ventral stream • Patient studies: • Patient DF: Visuomotor behaviour Visual input Visual perception

24. Ilussion distortion larger in judgment than in pointing However, with delayed pointing the illusion impact increases

25. Involvement of the ventral stream in visuomotor behaviour

26. Milner & Goodale (1995) • Perceptual identification requires different visual information than goal directed action REFERENCE Allocentric Egocentric

27. Hoe werkt dit voor de haptische waarneming? Zuidhoek, S., Kappers, A.M.L., van der Lubbe, R.H.J. and Postma, A. (submitted to Experimental Brain Research). Delay improves performance on a haptic spatial matching task.

28. Exploring the reference bar

29. Delay: waiting 10 s for the response signal

30. Response: setting the test bar parallel

31. Result: deviation in delay trials is smaller than in immediate trials

32. ref test immediate 10 second delay Na een pauze wordt de staaf minder aan de orientatie van de hand gecodeerd maar meer in ‘cognitieve’ termen (visualisatie strategie) => Kunnen blinden dit ook?

33. Remembering what was where: How is spatial information stored in memory? The hippocampal formation seems crucial (extending the ventral stream), receiving both egocentric and allocentric projections

34. Spatial performance in voles Males Females

36. The position of the hippocampus in the brain

37. Connections to and from the hippocampus Hippocampus brings multimodal, highly processed information together and consolidates it into memory

38. Place and direction cells are found in the hippocampal formation, which code location, direction, and speed and distance (theta rhythm).These functional properties form the basis for cognitive maps which support a) wayfindingb) goal identification and calculation of trajectoriesc) predicting interactions between agents and objectsd) other cognitive abilities (temporal, linguistic etc..)

39. In humans the hippocampus also supports spatial memory (Kessels, De Haan, Kappelle & Postma, Brain Reseerch Reviews, 2001) What about lateralisation? => Smith & Milner (1981, 1985, 1995)

40. Most studies suggest right sided lateralisation for spatial memory. However, this depends on the specific conditions

41. Apparently, there exists specific neural circuitries dedicated to spatial memory - dorsal & ventral stream provide egocentric and allocentric reference, resp. - left & right hemisphere provide categorical and coordinate spatial metrics, resp. - hippocampus supports cognitive map for (allocentric) spatial memory => at a functional level, it might be hypothesized that spatial memory is relatively autonomous, working in an automatic fashion

42. Hasher & Zacks (1979) Automatic Processes: -nonintentional -unaware -no load on central resources or attention -difficult to suppress Effortfull Processes: -intentional, voluntary -conscious -capacity limited -flexible Features coded automatically in memory: frequency and order of occurrence, location

43. Criteria for Automaticity No effects of: a) Intent to Learn b) Age c) Practice and Feedback d) Individual Differences/ Intelligence e) Concurrent Processing Loads

50. Conclusions on automaticity of spatial memory appear to depend upon the type of task used. Both implicit (automatic) and explicit (effortfull) influences may drive spatial memory performance Future research: to what extent do different neurological groups suffer specific implicit or explicit spatial memory impairments?