form, spatial and motion perception Flashcards
workshop 9
what is labrythitis?
An inner ear infection causes inflammation to the labyrinth. Symptoms include dizziness, nausea, hearing loss and vertigo.
what is the treatment/ management of labrythitis?
Usually, it will subside by itself within a few weeks. A GP may prescribe antihistamines or motion sickness tablets and for long term balance problems vestibular rehabilitation exercises may be advised
what is tinnitus?
Hearing noise (often ringing) with no external stimuli. Causes of tinnitus are not always clear but it is often linked to hearing loss, infection, Meniere’s disease, medication, an injury (builds pressure in the ear), or a problem with the circulatory system.
what is the treatment/ management of tinnitus?
Treatment will often depended on what the cause of the tinnitus is. For example, a doctor may be able to reduce symptoms of tinnitus by treating the underlying cardiac condition or infection. For many individuals, tinnitus cannot be cure and the NHS recommends the following methods of management:
○ Tinnitus counselling – to help you learn about your tinnitus and find ways of coping with it
○ Cognitive behavioural therapy (CBT) – to change the way you think about your tinnitus and reduce anxiety
○ Tinnitus retraining therapy (vestibular retraining)– using sound therapy to retrain your brain to tune out and be less aware of the tinnitus
what is vertigo?
An inner ear condition, thought be caused by otoconia fragments coming loose from their usual location, in which changes to the position of the head cause sudden bouts of vertigo. Symptoms include dizziness, vertigo, loss of balance, nausea and vomiting.
○ May be due to calcium carbonate within vestibular system that has become displaced.
§ Causes spinning effect.
what is the treatment/ management of vertigo?
It may subside by itself within a few weeks or months. A specialist may treat BPPV with a series of movements known as the canalith repositioning procedure.
how do we percieve form?
V1 Striate – V2 Extra Striate (ES) – Ventral stream (lots of neurons in a tract that lead towards the temporal lobe- recognition part of the temporal lobe) of ES cortex
Damage to ES cortex has led to understanding of regional functioning
○ Legions in the regions of the brain for perception of form.
Visual Agnosia
○ impaired object recognition
Areas identified in inferior temporal and lateral occipital complexes activated by object categories
Prosopagnosia
○ impaired facial recognition
Fusi-form face area (FFA) of temporal lobe
how do we percieve space?
Retina, striate and extra striate cortex (PRIMARY VISUAL CORTEX) (ECS)
Monocular (info from one eye only) but also Binocular (info from both eyes) (stereopsis from retinal disparity)
Disparity sensitive neurons found in the dorsal stream of ESC
Dorsal stream primarily involved, ending in posterior parietal lobe
○ ‘Where’ (is the object ion our visual field) and ‘How’ (will we act to the form) – guides action
All dorsal stream is interconnected to help us act in response to things in the environment
how do we percieve orientation and movement?
- Neurons in striate cortex sensitive to orientation…
Deciphered by the V1
○ Specifically sensitive= only fire if the line of a body is in a certain orientation. - ESC responsible for movement perception
- V5 or MT (medial temporal) region
○ Dorsal stream- info goes from V1 to V5 - Receives information from superior colliculus
- Medial Superior Temporal (MST) (further processing) responsible for processing of optic flow across retina - edge of occipital lobe and temporal lobe
○ If something is moving across our visual field- so the correct neurons fire at the correct time.
