Temporal Disorders in Left and Right Brain-Damaged Patients
Condition: Brain Disease
MeSH terms: Brain Diseases
Study type: Observational

Summary: 
      Time is an important function that permeates our everyday activities but it has been so far
      significantly under-investigated in neurological patients.

      For instance, it is known that right brain damaged (RBD) patients with spatial attentional
      deficit (neglect) are impaired in both the ability to estimate the duration of an event (Time
      Estimation), showing a time underestimation, and the ability of mentally moving in past and
      future time (Mental Time Travelling), showing a deficit in processing future events when they
      are projected in the past. After a leftward shift of spatial attention induced by prismatic
      adaptation (PA), both the underestimation and the ability to travel in time ameliorate.
      However, less is known about these abilities in left brain damaged (LBD) patients.

      Aims of this study are to investigate:

      i) the performance (in terms of accuracy and reaction times) of LBD and RBD patients on
      Mental Time Travelling; ii) the correlation between Mental Time Travelling and Time
      Estimation abilities; iii) the efficacy of a single session of PA inducing a leftward (L-PA)
      and a rightward (R-PA) attentional shift on Mental Time Travelling and Time Estimation
      abilities.

      A group of control subjects will be involved for comparison among groups.
    

Detailed description: 
      Time processing involves different abilities - i.e. estimating the duration of an event (Time
      Estimation) and moving in past and future time (Mental Time Travelling) - and it is a
      fundamental ability in everyday life. However, in neuropsychology, time processing is
      routinely neglected in the assessment of cognitive deficits in brain-damaged patients. This
      is surprising since time is an important function that permeates our activities: it is
      involved in perceiving mismatches in lip reading (milliseconds), estimating how long it takes
      to be ready for work (minutes), and planning how long it will take a manuscript to be
      accepted (usually months). Thus, impairment in processing time has important consequences in
      daily life.

      For instance, it is known that right brain damaged (RBD) patients with spatial attentional
      deficit (neglect) underestimate durations of milliseconds and show a deficit in processing
      future events when they are projected in the past.

      Moreover, previous studies have demonstrated that a leftward shift of spatial attention
      induced by prismatic adaptation (PA) determines an amelioration of both, time underestimation
      and the deficit in mental travel in time.

      The Mental Time Travelling, in particular, seems to involve different cognitive functions,
      among others, episodic memory and the ability to anticipate the future. Recent evidence
      suggests that these functions are mediated by neural circuits localized in the left
      hemisphere but no studies have investigated the ability of mentally moving in past and future
      time in left brain damaged (LBD) patients.

      Aims of this study are to investigate:

      i) the performance (in terms of accuracy and reaction times) of LBD and RBD patients on
      Mental Time Travelling; ii) the correlation between Mental Time Travelling and Time
      Estimation abilities; iii) the efficacy of a single session of PA inducing a leftward (L-PA)
      and a rightward (R-PA) attentional shift on Mental Time Travelling and Time Estimation
      abilities.

      A group of control subjects will be involved for comparison among groups.
    

Intervention name(s): Rightward Attentional Shift (R-PA); Leftward Attentional Shift (L-PA)
Intervention type(s): Behavioral; Behavioral
Intervention description(s): Patients will perform a session of 90 pointing movements toward a visual target presented on the right, the left or at the center of the visual field. This pointing task will be performed with prismatic googles inducing a rightward attentional shift.; Patients will perform a session of 90 pointing movements toward a visual target presented on the right, the left or at the center of the visual field. This pointing task will be performed with prismatic googles inducing a leftward attentional shift.
Observational model: Case-Control
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Patients will be selected from primary care clinic and they will be compared with matched
        healthy controls. Healthy controls will be selected from a community sample who volunteer
        to participate in the research.
      
Keywords: Time perception; Mental Time Travel; Prismatic adaptation; Left and Right Brain Damaged Patients