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Conditional associative learning examined in a paralyzed patient with amyotrophic lateral sclerosis using brain-computer interface technology.

Iversen I, Ghanayim N, Kübler A, Neumann N, Birbaumer N, Kaiser J - Behav Brain Funct (2008)

Bottom Line: A smiley was presented as a reward when he hit the correct target.In contrast, the patient showed clear evidence that A-B and B-C training had resulted in formation of equivalence classes.The brain-computer interface technology combined with the matching to sample method is a useful way to assess various cognitive abilities of severely paralyzed patients, who are without reliable motor control.

View Article: PubMed Central - HTML - PubMed

Affiliation: Institute of Medical Psychology, Goethe-University, Frankfurt am Main, Germany. j.kaiser@med.uni-frankfurt.de.

ABSTRACT

Background: Brain-computer interface methodology based on self-regulation of slow-cortical potentials (SCPs) of the EEG (electroencephalogram) was used to assess conditional associative learning in one severely paralyzed, late-stage ALS patient. After having been taught arbitrary stimulus relations, he was evaluated for formation of equivalence classes among the trained stimuli.

Methods: A monitor presented visual information in two targets. The method of teaching was matching to sample. Three types of stimuli were presented: signs (A), colored disks (B), and geometrical shapes (C). The sample was one type, and the choice was between two stimuli from another type. The patient used his SCP to steer a cursor to one of the targets. A smiley was presented as a reward when he hit the correct target. The patient was taught A-B and B-C (sample - comparison) matching with three stimuli of each type. Tests for stimulus equivalence involved the untaught B-A, C-B, A-C, and C-A relations. An additional test was discrimination between all three stimuli of one equivalence class presented together versus three unrelated stimuli. The patient also had sessions with identity matching using the same stimuli.

Results: The patient showed high accuracy, close to 100%, on identity matching and could therefore discriminate the stimuli and control the cursor correctly. Acquisition of A-B matching took 11 sessions (of 70 trials each) and had to be broken into simpler units before he could learn it. Acquisition of B-C matching took two sessions. The patient passed all equivalence class tests at 90% or higher.

Conclusion: The patient may have had a deficit in acquisition of the first conditional association of signs and colored disks. In contrast, the patient showed clear evidence that A-B and B-C training had resulted in formation of equivalence classes. The brain-computer interface technology combined with the matching to sample method is a useful way to assess various cognitive abilities of severely paralyzed patients, who are without reliable motor control.

No MeSH data available.


Percent correct for all trained and tested relations through steps 2 to 8. Relations above the graph indicate baseline relations and probe test relations. All indications are from Sample → Comparisons. Data are shown for both baseline trials and probe test trials; some sessions did not have probe test trials. Data from step 6, sessions 21 through 24, where steps 2, 3, 4 and 5 were repeated, are not shown to save space.
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Figure 5: Percent correct for all trained and tested relations through steps 2 to 8. Relations above the graph indicate baseline relations and probe test relations. All indications are from Sample → Comparisons. Data are shown for both baseline trials and probe test trials; some sessions did not have probe test trials. Data from step 6, sessions 21 through 24, where steps 2, 3, 4 and 5 were repeated, are not shown to save space.

Mentions: Fig. 5 shows percent correct for baseline and test trials for the symmetry, transitivity, and equivalence tests in steps 2 through 8. On the B → A symmetry tests, patient ER maintained a high accuracy on baseline trials and was 90% and 100% correct on probe trials showing clear evidence that the learned A → B relations were symmetrical without explicit training.


Conditional associative learning examined in a paralyzed patient with amyotrophic lateral sclerosis using brain-computer interface technology.

Iversen I, Ghanayim N, Kübler A, Neumann N, Birbaumer N, Kaiser J - Behav Brain Funct (2008)

Percent correct for all trained and tested relations through steps 2 to 8. Relations above the graph indicate baseline relations and probe test relations. All indications are from Sample → Comparisons. Data are shown for both baseline trials and probe test trials; some sessions did not have probe test trials. Data from step 6, sessions 21 through 24, where steps 2, 3, 4 and 5 were repeated, are not shown to save space.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2599893&req=5

Figure 5: Percent correct for all trained and tested relations through steps 2 to 8. Relations above the graph indicate baseline relations and probe test relations. All indications are from Sample → Comparisons. Data are shown for both baseline trials and probe test trials; some sessions did not have probe test trials. Data from step 6, sessions 21 through 24, where steps 2, 3, 4 and 5 were repeated, are not shown to save space.
Mentions: Fig. 5 shows percent correct for baseline and test trials for the symmetry, transitivity, and equivalence tests in steps 2 through 8. On the B → A symmetry tests, patient ER maintained a high accuracy on baseline trials and was 90% and 100% correct on probe trials showing clear evidence that the learned A → B relations were symmetrical without explicit training.

Bottom Line: A smiley was presented as a reward when he hit the correct target.In contrast, the patient showed clear evidence that A-B and B-C training had resulted in formation of equivalence classes.The brain-computer interface technology combined with the matching to sample method is a useful way to assess various cognitive abilities of severely paralyzed patients, who are without reliable motor control.

View Article: PubMed Central - HTML - PubMed

Affiliation: Institute of Medical Psychology, Goethe-University, Frankfurt am Main, Germany. j.kaiser@med.uni-frankfurt.de.

ABSTRACT

Background: Brain-computer interface methodology based on self-regulation of slow-cortical potentials (SCPs) of the EEG (electroencephalogram) was used to assess conditional associative learning in one severely paralyzed, late-stage ALS patient. After having been taught arbitrary stimulus relations, he was evaluated for formation of equivalence classes among the trained stimuli.

Methods: A monitor presented visual information in two targets. The method of teaching was matching to sample. Three types of stimuli were presented: signs (A), colored disks (B), and geometrical shapes (C). The sample was one type, and the choice was between two stimuli from another type. The patient used his SCP to steer a cursor to one of the targets. A smiley was presented as a reward when he hit the correct target. The patient was taught A-B and B-C (sample - comparison) matching with three stimuli of each type. Tests for stimulus equivalence involved the untaught B-A, C-B, A-C, and C-A relations. An additional test was discrimination between all three stimuli of one equivalence class presented together versus three unrelated stimuli. The patient also had sessions with identity matching using the same stimuli.

Results: The patient showed high accuracy, close to 100%, on identity matching and could therefore discriminate the stimuli and control the cursor correctly. Acquisition of A-B matching took 11 sessions (of 70 trials each) and had to be broken into simpler units before he could learn it. Acquisition of B-C matching took two sessions. The patient passed all equivalence class tests at 90% or higher.

Conclusion: The patient may have had a deficit in acquisition of the first conditional association of signs and colored disks. In contrast, the patient showed clear evidence that A-B and B-C training had resulted in formation of equivalence classes. The brain-computer interface technology combined with the matching to sample method is a useful way to assess various cognitive abilities of severely paralyzed patients, who are without reliable motor control.

No MeSH data available.