Left Hemisphere Stroke: Understanding The Link With Apraxia

Apraxia is a cognitive disorder that can occur after a stroke, interrupting an individual's ability to perform purposeful movements. It is often accompanied by aphasia, a language disorder, but it is considered a unique motor speech disorder. Apraxia can result from lesions to a complex network for motor cognition, and it is more common among people with damage to the left hemisphere of the brain.

Apraxia and aphasia are distinct, and cases of pure apraxia without aphasia are rare but offer an insight into the neural correlates that support articulatory planning. Apraxia of speech (AOS) impairs the coordination of complex articulatory movements needed for speech production. It is characterised by slow speech rate, segmentation of syllables, sound distortions, and particular difficulty with long and complex utterances.

A left hemisphere stroke can cause a lesion to the superior precentral gyrus of the insula, a small subregion of the insula, which can lead to AOS. Other brain regions that may be affected include the left precentral gyrus of the lateral motor cortex, Broca's area, and Area 55b.

Apraxia is a cognitive disorder that can occur after a stroke, affecting an individual's ability to perform purposeful movements

Apraxia is commonly associated with left hemisphere damage, particularly in the left parietal lobe, but it can also result from damage to other parts of the brain, including the right parietal lobe, temporal lobe, frontal lobe, or subcortical regions. The left superior longitudinal fascicle (SLF) has been implicated in apraxic deficits.

The most common type of apraxia is buccofacial (or orofacial) apraxia, which causes difficulty in making movements of the mouth, eyes, or face. Limb apraxia, which affects the use of arms and legs, is also common and includes ideational apraxia (difficulty organising actions to achieve a goal) and ideomotor apraxia (difficulty selecting and sequencing actions and using objects).

Apraxia can also affect speech, touch, writing and drawing skills, eye movements, and body movements. It can impact an individual's ability to do rehab activities, communicate with others, and complete common tasks, affecting their autonomy for work and daily activities.

The recovery process and rate of recovery from apraxia vary for each individual, but it typically spontaneously recovers in the first few months post-stroke and is responsive to rehabilitation.

Apraxia is more common among people with damage to the left hemisphere of the brain

Apraxia is a neuropsychological deficit that disrupts an individual's ability to perform purposeful movement. It is a cognitive disorder that can occur after a stroke, and is characterised by the inability to make purposeful movements, without any accompanying sensory or motor disturbances. Apraxia affects an individual's ability to perform gestures and movements, and can impact their ability to do rehab activities, communicate with others, and complete common tasks.

The most common type of apraxia is buccofacial (or orofacial) apraxia, which causes difficulty in making movements of the mouth, eyes, or face. The most common forms of limb apraxia are ideational apraxia and ideomotor apraxia, which cause difficulty in organising actions to achieve a goal, and difficulty in selecting and sequencing movements, respectively.

The recovery process and rate of recovery from apraxia will be different for each individual. Apraxia typically spontaneously recovers in the first few months post-stroke and is responsive to rehabilitation.section break

##section break

The Role of the Left Hemisphere in Apraxia

The left hemisphere plays a crucial role in motor control and language functions. Lesions to the left hemisphere can result in aphasia, a language disorder, and apraxia, a disorder of motor control. Apraxia after left hemisphere stroke is associated with lesions to a complex network for motor cognition, including dorso-dorsal, ventro-dorsal, and ventral processing streams.

Damage to specific regions in the left hemisphere, such as the superior precentral gyrus of the insula, portions of the inferior and middle frontal gyri, and precentral gyrus, have been implicated in apraxia of speech (AOS). AOS is a motor speech disorder that impairs the coordination of complex articulatory movements needed for speech production. It often co-occurs with aphasia but can also occur in pure cases without aphasia.

In summary, apraxia is more common among individuals with damage to the left hemisphere of the brain, particularly lesions affecting motor control and language functions. The left hemisphere plays a crucial role in the coordination of complex movements and articulatory movements required for speech production.

Apraxia can also result from damage to other parts of the brain, including the right parietal lobe, temporal lobe, frontal lobe, or subcortical regions

Apraxia is a motor disorder caused by damage to the brain, specifically the posterior parietal cortex or corpus callosum. It causes difficulty with motor planning to perform tasks or movements. The nature of the damage determines the severity of the disorder, and the absence of sensory loss or paralysis helps to explain the level of difficulty.

While apraxia is often caused by damage to the left hemisphere of the brain, it can also result from damage to other parts of the brain, including the right parietal lobe, temporal lobe, frontal lobe, or subcortical regions.

Damage to the right parietal lobe can cause a loss of spatial awareness on the opposite side of the body, known as hemispatial neglect. This can lead to a person behaving as if one side of space does not exist, such as shaving or applying makeup only to the right side of the face.

Lesions in the temporal lobe can also contribute to apraxia. In addition, damage to the frontal lobe, which is responsible for executive function, can interfere with speech planning, making it difficult to string together syllables or use complex words.

Furthermore, subcortical regions, such as the basal ganglia and the insula, have been implicated in apraxia. Damage to these areas can affect speech motor planning and result in impaired speech production.

Overall, apraxia can arise from damage to various parts of the brain beyond the left hemisphere, affecting movement, spatial awareness, and speech.

There are many different types of apraxia, including buccofacial, ideational, and ideomotor apraxia

Apraxia is a motor disorder caused by damage to the brain, specifically the posterior parietal cortex or corpus callosum. It is characterised by the inability to perform purposeful actions, either due to the inability to form a plan for movement (ideational apraxia) or the inability to execute the intended movement despite understanding the concept (ideomotor apraxia).

Buccofacial or orofacial apraxia is the most common type of apraxia. It is characterised by the inability to carry out facial movements on demand, such as winking, whistling, or licking one's lips. This suggests an inability to carry out volitional movements of the tongue, cheeks, lips, pharynx, or larynx on command.

Ideational apraxia is the inability to perform a purposeful motor act, either automatically or on command, because the patient no longer understands the overall concept of the act, cannot retain the idea of the task, or cannot formulate the motor patterns required. For example, a patient may put on a shoe before putting on a sock or try to write with a screwdriver.

Ideomotor apraxia is the inability to produce a movement on command but the ability to move automatically. For example, a patient may not be able to pick up a phone when asked to do so but can perform the action without thinking when the phone rings. Patients with ideomotor apraxia may also use their limb as an object rather than demonstrating how to use the object.

Apraxia impacts an individual's independence and ability to perform daily activities and rehabilitation tasks

Apraxia is a cognitive disorder that can occur after a stroke, affecting an individual's ability to make purposeful movements. It can limit a person's independence and ability to perform daily activities and rehabilitation tasks.

Apraxia is often caused by damage to the left hemisphere of the brain, particularly the left parietal lobe, but it can also result from damage to other areas such as the right parietal lobe, temporal lobe, frontal lobe, or subcortical regions. The disorder disrupts an individual's mental representation of actions, making it difficult to organise and imitate actions to achieve a goal.

The most common types of apraxia are buccofacial (or orofacial) apraxia, ideational apraxia, and ideomotor apraxia. Buccofacial apraxia causes difficulty in making movements of the mouth, eyes, or face. Ideational apraxia leads to challenges in organising actions to achieve a goal, while ideomotor apraxia results in difficulties with selecting, sequencing, and using objects.

Apraxia can significantly impact a person's ability to perform rehabilitation activities, communicate with others, and complete daily tasks. It can affect their capacity to relearn movements or acquire new skills, hindering their recovery process.

Interventions for apraxia aim to improve daily functioning and include strategy training, gesture training, direct activity training, and the use of assistive technology. While these interventions have shown some benefits, more research is needed to draw strong conclusions about their long-term effectiveness.

Frequently asked questions