Occurrence and Recovery of Different Neglect-Related Symptoms in Right Hemisphere Infarct Patients during a 1-Year Follow-Up.

OBJECTIVES: To examine the occurrence of and recovery from visual neglect-related symptoms with the focus on neglect laterality, ipsilateral orienting bias, and slowed processing speed in right hemisphere (RH) infarct patients during a 1-year follow-up. Furthermore, to propose guidelines for assessing processing speed alongside the Behavioural Inattention Test (BIT). METHODS: We studied three RH patient groups: neglect (N+), mild left inattention (MLI+), and non-neglect (N-) patients, and healthy controls. The BIT with some additional analyses was conducted at the acute phase and at 6 and 12 months. RESULTS: The N+ group's BIT score increased and originally lateralized omissions became more evenly distributed during the follow-up. The N+ and MLI+ groups' starting points were more rightward located than the healthy group's at the acute phase and at 6, and partly at 12 months. Patient groups were slower than the controls in performing cancellation tests at the acute phase. The N+ and MLI+ groups remained slower than the controls throughout the follow-up. CONCLUSIONS: During the first year after RH infarct, originally left-sided manifestation of neglect shifted toward milder non-lateralized attentional deficit. Ipsilateral orienting bias and slowed processing speed appeared to be rather persistent neglect-related symptoms both in neglect patients and patients with initially milder inattention. We propose some effortless, tentative ways of examining processing speed and ipsilateral orienting bias alongside the BIT to better recognize these neglect-related symptoms, and highlight the need to assess and treat patients with initially milder inattention, who have been under-recognized and under-treated in clinical work. (JINS, 2018, 24, 617-628).

Right hemisphere infarct patients and healthy controls: evaluation of starting points in cancellation tasks.

Patients with visual neglect (VN) tend to start cancellation tasks from the right. This exceptional initial rightward bias is also seen in some right hemisphere (RH) stroke patients who do not meet the criteria of VN in conventional tests. The present study compared RH infarct patients' (examined on average 4 days post-stroke) and healthy controls' starting points (SPs) in three cancellation tasks of the Behavioural Inattention Test (BIT). Furthermore, task-specific guideline values were defined for a normal SP to differentiate the performance of healthy subjects from that of patients with subclinical inattention. Conventional tests indicated that 15 of the 70 RH infarct patients had VN. The control group comprised 44 healthy volunteers. In each task, the VN group started the cancellations mainly from the right. The non-neglect and healthy groups initiated most cancellations from the left, more so in the healthy group. Starting more than one BIT task outside the guideline value indicated pathological inattention, as this was typical among the VN patients, but exceptional among the healthy subjects. One-third of the non-neglect patients showed pathological inattention by starting more than one task outside the guideline value. Clinical assessment of VN should, therefore, include an evaluation of the SPs to detect this subtle form of neglect.