Week 11 Cue Cards

neuroanatomy of sensation

• Primary Sensory Cortex: Located in the occipital gyrus.

• Thalamus

  • Ventral Posterior Medial (VPM) and Ventral Posterolateral (VPL) parts process and relay sensory information from the face and body to the central cortex.

• Spinal Cord Systems

  • Dorsal Column Medial Lemniscal System: Located in the posterior panniculus; responsible for discriminative touch and proprioception.

  • Anterolateral System: Carries sensations of pain, temperature, and light touch to higher centres.

principles of sensory assessment

• Purpose: Evaluate how an individual processes and responds to sensory input (e.g., touch, sound, movement).

• Sensory Challenge: Assess over or under sensitivity.

• Impact Analysis: Determine how sensory impairments affect functional activities and emotional regulation.

• Accuracy Considerations: Dependence on patient's responses, especially those with cognitive deficits.

levels of arousal

• Alert: Patient is awake, attentive, and interacts appropriately.

• Lethargic: Appears drowsy, may fall asleep without adequate stimulation, struggles to focus.

• Obtunded: Difficult to arouse, frequently confused when awake; interaction is unproductive.

• Stupor: Responds only to strong noxious stimuli, often unresponsive otherwise.

• Coma: Cannot be aroused; responses are reflexive at best.

attention types

• Focused Attention: Ability to respond to specific stimuli; lowest level of attention.

• Sustained Attention: Ability to maintain steady response, typically around 15-20 minutes for adults.

• Selective Attention: Ability to focus amid distractions.

• Alternating Attention: Ability to switch focus between tasks; deficits cause inefficient transitions.

• Divided Attention: Ability to respond to multiple tasks simultaneously; deficits hinder performance on dual tasks.

• Assessment Techniques: Utilise progressive challenging tasks, Stroop test for attention evaluation.

orientation assessment

• Oriented x3: Patient correctly identifies time, place, and person.

• Partial Orientation: Identifies 1-2 domains accurately; noted as oriented to time/place/person.

disorders of consciousness

• Coma: Prolonged unresponsiveness; no response to stimuli, breathing may depend on external support.

• Unresponsive Wakefulness: Awake without awareness; no purposeful responses.

• Minimal Conscious State: Inconsistency in signs of awareness; may follow simple commands or make eye contact.

cognitive assessment

• Nature: Encompasses understanding, memory, reasoning, language acquisition and use.

• Key Areas:

  • Fund of Knowledge: Sum of life experiences and learned information.

  • Calculation Abilities: Fundamental math skills; differentiates acquired loss (due to injury) from developmental disorders like dyscalculia.

  • Interpretation of Problems: Ability to understand figurative language, indicative of executive function.

memory systems

• Conscious vs. Subconscious Memory: Guides learning and personal identity; includes visual and auditory memory.

• Short-term Memory: Holds information for seconds to minutes; long-term memory retains information over extended periods.

• Cognitive Impairment Assessment: Observations, screening tools, neuropsychological tests.

problem solving

• Definition: Use of memory, experience, and reasoning to achieve desired outcomes.

• Skills Involved: Planning, flexibility, knowledge application in new contexts.

• Assessment Methods: Functional testing and standardized tools (e.g., MoCA, Trail Making Test).

specific assessment tools

Glasgow Coma Scale (GCS)

• Used to assess consciousness level; evaluates motor response, verbal response, eye opening.

• Score Range: 3 (deep coma) to 15 (fully awake). Scores below 8 indicate severe impairment.

Galveston Orientation and Amnesia Test (GOAT)

• Measures orientation recovery following a traumatic brain injury; assesses post-traumatic amnesia.

• Score above 75 for two consecutive days indicates recovery from post-traumatic amnesia.

Rancho Los Amigos Scale

• A ten-level scale evaluating cognitive and behavioural recovery from brain injuries; assesses patient's consciousness and capacity for purposeful actions.

visual perceptual processing skills

Definition and Importance

• Ability to interpret visual information; includes visual memory, spatial relationships, decision making.

Components of Visual Perception

• Visual Memory: Storing and recalling visual data.

• Pattern Recognition: Identifying trends or irregularities; crucial for navigation and decision making.

• Visual Scanning: Efficiently moving eyes to gather visual stimuli; vital for tasks such as reading.

• Visual Attention: Selects and focuses on relevant information while ignoring distractions.

visual acuity and visual fields

Visual Acuity

• Ability to see small details; impairment can indicate cognitive decline.

• Assessment: Progressive eye chart reading; essential for daily functioning.

Visual Fields Assessment

• Area visible to the eye; includes central and peripheral fields.

• Peripheral Vision: Affected by cognitive function; assessed using confrontation tests.

• Cortical Blindness: Occurs due to brain damage; patients have intact eyes but cannot interpret visual stimuli.

neuroanatomical contributions to visual function

Key Structures

• Optic Nerve: Transmits visual information from the retina to the brain.

• Optic Chiasm: Convergence and partial crossing of optic nerve fibres.

• Optic Tract & Geniculate Nucleus: Transmit and relay visual information.

Lesion Impacts on Vision

• Optic Nerve Lesion: Complete loss of vision in the affected eye.

• Optic Chiasm Lesion: Loss of temporal visual field in both eyes.

• Optic Tract Lesion: Loss of vision in the contralateral visual field.

depth perception

Definition and Importance

• Ability to judge distances and navigate the environment.

Cues for Depth Perception

• Oculomotor Cues: Eye positioning and muscle tension.

• Binocular Vision: Information from both eyes creates depth perception.

Assessment of Depth Perception

• Standard Tests: Including the Randot Stereotest for stereopsis evaluation; typically conducted by OTs or optometrists.

• Cover-Uncover Test: Evaluates eye alignment, important for identifying oculomotor issues.

Assessment of Oculomotor Function

• Ability to track movements and maintain focus; tested through various techniques.

• Oculomotor Palsies: Impact voluntary eye movements affecting visual function.

vestibular system interactions

Definition

• Involved in balance and spatial orientation; integrates sensory input for postural control.

Assessment of Vestibular Function

• Eye movements correlated with head movement to maintain visual stability.

perceptual issues in sensory impairments

Body Image and Schema

• Awareness of body parts in relation to oneself and the environment.

• Asomatognosia: Inability to recognise body parts; associated with parietal lobe injury.

Spatial Relations and Navigation

• Ability to judge positions of objects; deficits lead to mobility issues.

apraxia and its impacts on function

Definition

• Impairment in the ability to carry out purposeful movements despite intact sensation and coordination.

Types of Apraxia

• Ideomotor Apraxia: Difficulty producing movements upon command.

• Ideational Apraxia: Difficulty with sequencing actions.

Assessment of Apraxia

• Use of gestures and pantomime; observational assessments aid in identification.

neglect in sensory impairments

Definition and Characteristics

• Unilateral neglect affects attention and awareness on one side of the body.

• Prevalent in stroke survivors; often characterised by spatial neglect.

Assessment Techniques

• Various standardised tools and observational methods used for diagnosis.

Management Strategies

• Cognitive training, visual scanning cues, and sensory stimulation interventions to enhance awareness.

cutaneous sensation testing

Light Touch – Detection

Findings:

• No sensation

• Asymmetry

• Heightened response

Significance:

• Anaesthesia/paraesthesia

• Peripheral or central nervous system involvement

• test dermatomes when suspected spinal/nerve root lesion

Safety Concerns if Impaired:

• Falls/balance issues

• Skin integrity breakdown

Light Touch – Localisation

Findings:

• Sensory extinction

• Feels but cannot locate

• Cannot feel + cannot locate

• Feels + can locate

Significance:

• Peripheral or central involvement

Sensory Quantification (Temperature/Texture/Weight)

Findings:

• Able/unable to identify

• Able/unable to feel

Significance:

• Loss of sensory discrimination

• Peripheral or central lesion

Sensory Extinction

Findings:

• Can detect unilateral and bilateral

• Unilateral intact but bilateral impaired (extinction)

Significance:

• Extinction → contralateral parietal lobe lesion

Double Simultaneous Stimulation

Findings:

• Sensory loss or extinction

Significance:

• Peripheral or central involvement

Stereognosis

Findings:

• Can identify objects

• Cannot identify objects (astereognosis)

Significance:

• Contralateral parietal lobe lesion

• Somatosensory cortex involvement

• Possible dorsal column lesion

• reduced hand function

• difficulty finding objects, dressing, grooming

Proprioception (Joint Position Sense)

Findings:

• Able or unable to detect direction of movement

Significance:

• Peripheral or central lesion

• Posterior column dysfunction → balance problems

vision testing

Smooth Pursuit

Findings:

• Smooth tracking

• Saccadic or jumpy tracking

Significance:

• Eye movement control impairment

  Function:

• Tracking + gaze stabilisation

Convergence/Divergence

Normal: Converge to 6 cm from nose

Symptoms of insufficiency:

• Double vision

• Headaches

• Eye strain

• Difficulty reading

Visual Fields

Normal limits:

• 90° lateral

• 60° up

• 50° down

Impairment Example:

• Seeing finger only near midline → homonymous hemianopia

Visual Acuity (Finger Counting)

Findings:

• Able/or unable to identify finger number

Significance:

• Helps detect field loss

• Processing issues

Visual Extinction

Findings:

• Can detect single stimuli

• Misses one stimulus during bilateral presentation

Significance:

• Unilateral brain damage → neglect

Functional implications:

• Uses affected side less

• Poor postural control

visual pathway lesions

Visual Field Deficit	Where the Lesion Is	Explanation
Monocular blindness (loss of vision in one eye)	Optic nerve (before chiasm)	Cuts off all visual information from that eye.
Bitemporal hemianopia (loss of outer halves of both visual fields)	Optic chiasm (midline)	Compression of crossing nasal fibres → lose temporal visual fields.
Binasal hemianopia (loss of inner halves of both fields; rare)	Lateral optic chiasm	Damage to non-crossing temporal fibres on both sides.
Contralateral homonymous hemianopia	Optic tract OR entire optic radiation OR primary visual cortex (one side)	Lose the opposite visual field completely.
Contralateral upper quadrantanopia (“pie in the sky”)	Temporal lobe (Meyer’s loop)	Temporal optic radiations carry upper field info.
Contralateral lower quadrantanopia (“pie on the floor”)	Parietal lobe optic radiations	Parietal fibres carry lower field info.
Macular sparing homonymous hemianopia	Occipital cortex (PCA stroke)	Macula receives dual blood supply → preserved central vision.

apraxia assessment

• Pantomime: pretend tool use

• Meaningful gestures: wave, thumbs up

• Meaningless gestures: finger-spreading, tapping

• Luria 3-step: fist → chop → palm

7 princples of Sense

o   Select

§  Texture: grids

§  Common textures

§  Limb positions

§  Objects – pressure

§  Shape

§  Manipulating objects

§  3 things we can all feel: Chemical reaction, pressure, temperature

o   Attentive exploration

§  Focused attention

o   Feedback

§  Joint proprioception

§  Vision and touch

o   Calibrate

§  Through vision

§  Imagine the sensation before trying

o   Anticipate

§  Knows what to expect to feel

§  Distinctive differences in sensations

o   Repeat and progress

§  Consolidate learning

§  Training progresses to more difficult discriminations

§  Vital to establish and strengthen connections

o   Transfer

§  Enhance transfer of skills

§  Feedback given

§  Patient with stroke drives own recovery