Higher Order Cerebral Function

Mental Status Exam Overview

- level of consciousness

- attention

- orientation

- language

- memory

- executive function

level of consciousness: Neuroanatomy

- RAS: brainstem (midbrain pons)

- Thalamus: relay for cortical activation

- diffuse cerebral cortex

level of consciousness: functions

maintains arousal and wakefulness

level of consciousness: lesion brainstem

coma

level of consciousness: lesion bilateral cortical damage

decreased consciousness

level of consciousness: Clinical testing

observe responsiveness to voice, touch, pain

level of consciousness: PT implications

- decreased LOC leads to unsafe mobility, poor participation and high fall risk

- acts like the brains "on/off switch" for consciousness

Orientation: Neuroanatomy

- frontal lobes: awareness and integration

- hippocampus: memory for time/place

- Reticular System: alertness baseline

Orientation: Function

- person

- place

- time

- situation

Orientation: Lesion Diffuse cortical dysfunction

- disorientation

- seen in delirium, TBI, Dementia

Orientation: Clinical testing

ask basic orientation questions

Orientation: PT implications

disorientated patients need constant supervision and cueing

Attention: Neuroanatomy

- prefrontal cortex (DLPFC): sustained attention

- Parietal Lobe (especially R): spatial attention

- anterior cingulate cortex: focus and error detection

Attention: Function

ability to focus, shift, and sustain mental effort

Attention: Lesions Right parietal

neglect

Attention: lesions Frontal

distractibility

Attention: Clinical Testing

- digit span

- serial 7s

- months backward

Attention: PT implication

poor attention = decreased motor learning, decreased carryover

Memory: Neuroanatomy

- hippocampus: new memory formation

- medial temporal lobe

- prefrontal cortex: working memory

- mammillary bodies (papez circuit)

Memory: Function

- immediate (seconds)

- short-term (minutes)

- long-term (days-years)

Memory: Lesions Hippocampus

anterograde amnesia

Memory: Lesions Diffuse

dementia

Memory: Clinical Testing

recall 3 objects after delay

Memory: PT Implication

poor memory leads to repeition, written instructions needed

Language: Neuroanatomy

- brocas area (left frontal): motor speech

- wernickes area (left temporal): comprehension

- Arcuate fasciculus: connection

- angular gyrus: reading and writing

Language: Functions

- speaking

- understanding

- naming

- repetition

Language: Lesions Broca

non-fluent aphasia

Language: Lesions wernickes

fluent aphasia

Language: Lesion Arcuate

conduction aphasia

Language: Clinical testing

- naming objects

- following commands

- repetition

Language: PT Implication

- must adapt communication

- short commands

- demonstration

- visual cues

Executive Function: Neuroanatomy, Prefrontal Cortex

- dorsolateral: planning

- Orbitofrontal: behavior

- Medial: motivation

Executive Function: Functions

- planning

- judgement

- problem solving

- decision-making

Executive Function: Lesions frontal lobe

- impulsivity

- poor judgement

- apathy

Executive Function: Clinical testing

- abstract thinking

- problem solving questions

Executive Function: PT implications

- decreased safety awareness

- poor compliance

- requires structured rehab approach

Principle of Localization

- specific brain regions control specific functions

- damage to that region: predictable clinical deficits

Principle of Lateralization

certain functions are dominant in one hemisphere

Frontal Lobe, Function and Clinical Deficit

- motor, executive function

- weakness, poor planning

Parietal lobe, Function and Clinical Deficit

- sensation, spatial awareness

- sensory loss, neglect

Temporal Lobe, Function and Clinical Deficit

- memory, language

- aphasia, memory loss

Occipital Lobe, Function and Clinical Deficit

- vision

- visual field deficits

Cerebellum, Function and Clinical Deficit

- coordination

- ataxia

Brainstem, Function and Clinical Deficit

- consciousness, CNs

- Coma, CN deficits

Left vs Right Hemisphere: Language

- LH: Yes

- RH: No

Left vs Right Hemisphere: Speech Production

- LH: Brocas Area

- RH: Minimal

Left vs Right Hemisphere: Comprehension

- LH: wernickes area

- RH: minimal

Left vs Right Hemisphere: Math/Logic

- LH: strong

- RH: limited

Left vs Right Hemisphere: Spatial Awareness

- LH: limited

- RH: Strong

Left vs Right Hemisphere: Attention

- LH: moderate

- RH: Dominant

Left vs Right Hemisphere: Emotional Tone (prosody)

- LH: limited

- RH: strong

Language is not one area its a

connected network in the dominant (usually LEFT) hemisphere

Language aspects

- brocas area

- wernickes area

- arcuate fasciculus

arcuate fasciculus is

a white matter association tract that connects Wernickes area to Brocas Area

arcuate fasciculus is the critical pathway for

communication within the language network

Language Components

- fluency

- comprehension

- repetition

- naming

Brocas Aphasia Location

left inferior frontal gyrus (Brocas area)

Brocas Aphaseia SXS

- non-fluent speech

- good comprehension

- poor repetition

Wernickes Aphasia location

left posterior superior temporal gyrus (wernickes area)

Wernickes Aphasia SXS

- fluent but meaningless speech

- poor comprehension

Global Aphasia location, Large lesion involving BOTH

- brocas area

- wernickes area

- surrounding cortex

Global Aphasia is ultimately

severe impairment in all domains

Conduction Aphasia Location

arcuate fasciculus (white matter tract)

Conduction Aphasia SXS

- good comprehension

- poor repetition

Bedside language exam features

- naming

- commands

- repetition

- reading/writing

Disconnection Syndrome is a

neurological disorder caused by disruption of communication between brain regions, not necessarily damage to the regions themselves

In Disconnection syndrome, the brain areas may be intact BUT

the connections (white matter tracts) are damaged

Disconnection Syndrome, corpus callosum lesions

loss of integration

Hemineglect is a

disorder of attnetion, NOT primary sensation or vision in which the pt ignores one side of space/body (most commonly LEFT side)

Hemineglect Most common lesions

- right parietal lobe (inferior parietal lobule)

- Right side matters more because the R hemisphere attends to both sides of space

- left side hemisphere mainly attends to Right side

Hemineglect, Right lesion

severe left neglect

Hemineglect, Left Lesion

mild or no neglect

neglect testing

- line bisection

- clock drawing

- cancellation test

Motor Intentional Neglect is a

disorder where the pt can move the limb (no primary weakness) but fails to initiate or use it spontaneously, usually on contralateral side

Motor Intentional Neglect most commonly

- left sided underuse after right hemisphere lesions

- movement possible but not initiated

Frontal Lobe functions

- executive function

- behavior

- motor planning

Frontal Lobe Syndrome: Disinhibition

loss of social restraint and impulse control

Frontal Lobe Syndrome: Poor Judgement

impaired decision making and reasoning

Frontal Lobe Syndrome: Apathy

lack of motivation or intitation

PT Implications: Patient may

- ignore safety instructions

- be impulsive during mobility

- requires close supervision, clear boundaries, structured sessions

PT Implications: Poor carryover of instructions needs:

- step by step guidance

- repetition

- simplified tasks

PT Implications: Pt appears lazy but

is neurologically impaired

PT Implications: Use

- external cueing

- goal-directed tasks

- frequent encouragement

Visual Processing

- Ventral: object recognition

- Dorsal: spatial awareness

Visual Processing PT Implications: Pt may

- miss objects

- misjudge distance

Visual Processing PT Implications: USE

- visual scanning training

- guided reaching

- environmental modifications

Visual Disorders, Agnosia

inability to recognize objects despite normal sensory function

Visual Disorders, Prosopagnosia

inability to recognize familiar faces

Visual Disorders PT Implications: Pt may

- misuse objects

- struggle with ADLS

Visual Disorders PT Implications: Struggle with ADLS use

- tactile input

- verbal cueing

- repetition

Visual Disorders PT Implications: Pt also may

- not recognize therapist

- fall anxious/confused

Visual Disorders PT Implications: Pt when anxious and confused strategies

- introduce yourself repeatedly

- use name cues

- maintain consistency

Auditory Hallucinations

- hearing voices

- temporal lobe involvement

Attention Disorders

- ADHD

- neglect

In delirium, the brain is

temporarily not functioning properly

delirium leads to

- confusion

- poor attention

- disorganized thinking

delirium key features: acute onset

develops in hours to days

delirium key features: fluctuating course

comes and goes throughout the day

delirium key features: Impaired Attention

cannot focus or stay on task

delirium key features: Altered Consciousness

may be drowsy or agitated