Cognitive Functioning in Individuals with Spinal Cord Injury (SCI)

Nancy D. Chiaravalloti, Ph.D.

Director of Neuroscience and Neuropsychology and Traumatic Brain Injury Research

Kessler Foundation

Professor of Physical Medicine and Rehabilitation Rutgers-New Jersey Medical School

Disclosures

Dr. Chiaravalloti has no disclosures to report.

Outline • Defining Cognition

– Cognitive domains

• SCI and Cognitive Functioning

• Potential causes/ sources of Cognitive

Deficits in SCI

Outline • Defining Cognition

– Cognitive domains

• SCI and Cognitive Functioning

• Potential causes / sources of Cognitive

Deficits in SCI

Cognition

• "the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses.”

– conscious and unconscious

– Concrete and abstract

– Intuitive and conceptual

Cognition • Includes the concepts of

– Knowledge

– Attention

– Memory

– Judgment and evaluation

– Reasoning and "computation”

– Problem solving and decision making

– Comprehension and language production

Cognition

• Cognitive processes use existing knowledge and generate new knowledge

• Ongoing changing process.

• We rely on cognition EVERY day.

• Central to who we are and what we do with our lives.

Impact of Cognition on Daily Life

• Cognitive deficits lead to: – Depression, anxiety – Decreased participation – Increased unemployment – Decreased quality of life

So What? • Age of onset and career productivity

– Career development may slow or stop

• Physical and cognitive impairments lead to early retirement

• Biggest Obstacles to maintaining employment – information processing deficits – memory deficits

What does this mean?

• MUST identify cognitive deficits when they present and treat them effectively

• First step: Reliably identify the deficits experienced

Cognitive Domains

• Attention • Working Memory • Processing Speed • Visuospatial processing • Long Term Memory • Executive Functioning

Intelligence - not a cognitive domain, culmination of cognitive abilities

Breaking Down the Domains

• Attention – Simple – Sustained – Divided

• Working Memory – Maintenance – Manipulation

• Long Term Memory – Verbal and Non-verbal – Episodic, procedural – Retrospective, Prospective – Encoding, Consolidation, Retrieval

• Executive Functioning – Fluency – Mental flexibility – Disinhibition – Problem Solving – Abstract Reasoning

Learning & Memory

Attention Working Memory

Visuospatial Processing

Executive Functions

Processing Speed

Outline • Defining Cognition

– Cognitive domains

• SCI and Cognitive Functioning

• Potential causes / sources of Cognitive

Deficits in SCI

Sample Characteristics Tetraplegia N=18 C3-C8

High Para N=5 T1-T5

Low Para N=14 T7-T12

Older Controls N=14

Age Matched Controls N=18

Age

38±8

39±6

34±6

60±3

36±8

Duration of Injury

14.2±8.9

13.6±5.1

8.4±4.5

n/a

n/a

Education

14.1±2.8

13.8±1.5

13.3±2.2

16.3±2.5

15.9±2.0

Our Data (unpublished)

Our Data (unpublished)

Our Data (unpublished)

Our Data (unpublished)

Thinking about treatment

• EXACTLY what is the deficit? – Off to a good start – Learning, immediate recall, long term recall – Processing speed

• Are there other deficits?

Learning & Memory

Attention Working Memory

Visuospatial Processing

Executive Functions

Processing Speed

How does Processing Speed affect memory?

• When information is coming in fast – Cannot process all of it – Certainly cannot process it correctly

• All working memory tasks requiring one to process information within a circumscribed period of time – Tasks may not be timed, but there is a decay of

information (decay occurs over time) • What does this mean?

– Poor PS poor learning and memory

Impact of PS on treatment efficacy

CVLT Learning Trials

PS Intact PS Impaired

* No significant group difference pre-treatment

p=.006

Chart1

Trial 1Trial 1

Trial 2Trial 2

Trial 3Trial 3

Trial 4Trial 4

Trial 5Trial 5

Treatment

Control

6.41

5.84

10.14

8.68

11.72

10.03

12.79

10.52

12.93

10.94

Sheet1

TreatmentControl

Trial 16.415.84

Trial 210.148.68

Trial 311.7210.03

Trial 412.7910.52

Trial 512.9310.94

To resize chart data range, drag lower right corner of range.

Chart1

Trial 1Trial 1

Trial 2Trial 2

Trial 3Trial 3

Trial 4Trial 4

Trial 5Trial 5

Treatment

Control

5.64

5.8

7.36

8

8.86

8.6

9.93

9.3

9.64

9

Sheet1

TreatmentControl

Trial 15.645.8

Trial 27.368

Trial 38.868.6

Trial 49.939.3

Trial 59.649

To resize chart data range, drag lower right corner of range.

Memory Impairment

PS Impaired PS

Intact

If memory still impaired,

treat the memory deficit

Memory Treatment

Treat PS

Model Decision Tree

Memory Impairment

PS Impaired PS

Intact

If memory still impaired,

treat the memory deficit

Memory Treatment

Treat PS

Model Decision Tree

Need to know the source of the deficit

Outline • Defining Cognition

– Cognitive domains

• SCI and Cognitive Functioning

• Potential sources / causes of Cognitive

Deficits in SCI

Potential Causes of Cognitive Deficits in SCI Population

• Cerebrovascular Insufficiency • Concomitant TBI

– Dual Diagnosis – TBI may be mild

• Both

Methods for Determining Cause

• Cerebrovascular Testing during cognitive performance

• Imaging – Brain – DTI, fMRI

• Observing trajectory of change

MAP Data (unpublished)

MAP and Memory Data (unpublished)

MFV Data (unpublished)

MFV and Memory Data (unpublished)

fMRI Data (unpublished) subset (n=29)

Increased activation in frontal and parietal areas in LP compared to AM (red), Less activation (blue) in memory areas

More activation in frontal and motor regions than AM controls during PS task, performance required more cerebral resources in Tetra

** fMRI findings corroborate behavioral findings

What does this mean? Informing Treatment

• Data indicate a contribution of cerebrovascular insufficiency – Treat low BP and observe cognition

• Ongoing with Mitodrine • Observing immediate and long term effects

• Also observing fMRI abnormalities – Early CR

• Launching cognitive rehab trial in SCI – Treat for mild TBI early

Collaborators

Jill Wecht, PhD Glenn Wylie, D.Phil.

Trevor Dyson-Hudson, MD Steve Kirshblum, MD

William Baum, MD Kathy Chiou, PhD

Erica Weber, PhD Ekaterina Dobryakova, PhD

Nancy Moore, MA Caitlyn Katzelnick, M.A.

Christopher M. Cirnigliaro, M.S.

Funding Sources

NJ Commission on SCI Research

Craig Nielson Foundation

Kessler Foundation

Kessler Institute for Rehabilitation

Cognitive Functioning in Individuals �with Spinal Cord Injury (SCI)��Slide Number 2Slide Number 3Slide Number 4CognitionCognitionCognitionImpact of Cognition on Daily LifeSo What? What does this mean?Cognitive DomainsBreaking Down the DomainsSlide Number 13Slide Number 14Slide Number 15Sample CharacteristicsOur Data (unpublished)Our Data (unpublished)Slide Number 19Slide Number 20Thinking about treatmentSlide Number 22How does Processing Speed affect memory?Impact of PS on treatment efficacySlide Number 25Slide Number 26Slide Number 27Potential Causes of Cognitive Deficits in SCI PopulationMethods for Determining CauseSlide Number 30MAP and Memory Data (unpublished)MFV Data (unpublished)MFV and Memory Data (unpublished)fMRI Data (unpublished)�subset (n=29)What does this mean?�Informing TreatmentCollaboratorsFunding Sources